New processing methods. Materials processing technology

Metal in its various forms, including numerous alloys, is one of the most popular and widely used materials. It is from it that a lot of parts are made, as well as a huge number of other popular items. But in order to obtain any product or part, you need to make a lot of effort, study the processing processes and properties of the material. The main types of metal processing are carried out according to different principles of influence on the surface of the workpiece: thermal, chemical, artistic influence, using cutting or pressure.

Thermal effect on a material is the influence of heat in order to change the necessary parameters regarding the properties and structure of a solid substance. The process is most often used in the production of various machine parts, and at different stages of production. The main types of heat treatment of metals: annealing, hardening and tempering. Each process affects the product in its own way and is carried out at different temperatures. Additional types of influence of heat on a material are operations such as cold treatment and aging.

Technological processes for producing parts or workpieces through force on the surface being processed include different types of metal forming. Among these operations, there are several that are most popular in use. Thus, rolling occurs by compressing the workpiece between a pair of rotating rolls. Rolls can be of different shapes, depending on the requirements for the part. When pressing, the material is enclosed in a closed form, from where it is then extruded into a smaller form. Drawing is the process of drawing a workpiece through a gradually narrowing hole. Under the influence of pressure, forging, volumetric and sheet stamping are also performed.

Features of artistic metal processing

Creativity and craftsmanship reflect the various types of artistic metalworking. Among them, we can note a couple of the most ancient, studied and used by our ancestors - this is casting and. Although not much behind them in terms of appearance was another method of influence, namely, minting.

Embossing is the process of creating pictures on a metal surface. The technology itself involves applying pressure to a previously applied relief. It is noteworthy that embossing can be done both on a cold and on a heated working surface. These conditions depend, first of all, on the properties of a particular material, as well as on the capabilities of the tools used in the work.

Methods of mechanical processing of metals

The types of mechanical processing of metals deserve special attention. In another way, mechanical action can be called the cutting method. This method is considered traditional and the most common. It is worth noting that the main subtypes of this method are various manipulations with the working material: cutting, cutting, stamping, drilling. Thanks to this method, it is possible to obtain the desired part with the required dimensions and shape from a straight sheet or block. With the help of mechanical action, you can achieve the necessary qualities of the material. Often this method is used when it is necessary to make a workpiece suitable for further technological operations.

Types of metal cutting processing are represented by turning, drilling, milling, planing, chiselling and grinding. Each process is different, but in general cutting is the removal of the top layer of the working surface in the form of chips. The most commonly used methods are drilling, turning and milling. When drilling, the part is fixed in a stationary position and is impacted with a drill of a given diameter. During turning, the workpiece rotates and the cutting tools move in specified directions. When using the rotational movement of the cutting tool relative to a stationary part.

Chemical processing of metals to increase the protective properties of the material

Chemical treatment is practically the simplest type of impact on a material. It does not require much labor or specialized equipment. All types of chemical processing of metals are used to give the surface a certain appearance. Also, under the influence of chemical exposure, they strive to increase the protective properties of the material - resistance to corrosion and mechanical damage.

Among these methods of chemical influence, the most popular are passivation and oxidation, although cadmium plating, chrome plating, copper plating, nickel plating, galvanizing and others are often used. All methods and processes are carried out with the aim of increasing various indicators: strength, wear resistance, hardness, resistance. In addition, this type of processing is used to give the surface a decorative appearance.

Chemical and electrical methods for processing materials

When processing metals by cutting, obtaining parts of the required dimensions is achieved by removing chips from the surface of the workpiece. Chips are thus one of the most common wastes in metalworking, amounting to approximately 8 million tons per year. At the same time, at least 2 million tons are waste from processing high-alloy and other especially valuable steels. When processing on modern metal-cutting machines, up to 30 - 40% of the metal from the total mass of the workpiece often goes into chips.

New methods of metal processing include chemical, electrical, plasma, laser, ultrasonic, and hydroplastic metal processing.

Chemical processing uses chemical energy. Removal of a certain layer of metal is carried out in a chemically active environment (chemical milling). It consists of time and place controlled dissolution of the metal in baths. Surfaces that cannot be treated are protected with chemically resistant coatings (varnishes, paints, photosensitive emulsions, etc.). The constancy of the etching rate is maintained due to the constant concentration of the solution. Using chemical processing methods, local thinning and cracks are obtained; "waffle" surfaces; treat hard-to-reach surfaces.

With the electrical method, electrical energy is converted into thermal, chemical and other types of energy that are directly involved in the process of removing a given layer. In accordance with this, electrical processing methods are divided into electrochemical, electroerosive, electrothermal and electromechanical.

Electrochemical processing is based on the laws of anodic dissolution of metal during electrolysis. When a direct electric current passes through the electrolyte, chemical reactions occur on the surface of the workpiece, which is connected to the electrical circuit and serves as the anode, and compounds are formed that go into solution or are easily removed mechanically. Electrochemical processing is used for polishing, dimensional processing, honing, grinding, cleaning metals from oxides, rust, etc.

Anodic-mechanical processing combines electrothermal and electromechanical processes and occupies an intermediate place between electrochemical and electroerosive methods. The workpiece being processed is connected to the anode, and the tool to the cathode. Metal discs, cylinders, tapes, and wire are used as tools. The processing is carried out in an electrolyte environment. The workpiece and tool are given the same movements as in conventional machining methods. The electrolyte is fed into the processing zone through a nozzle.

When a direct electric current is passed through an electrolyte solution, the process of anodic dissolution of the metal occurs, as in electrochemical processing. When the cathode tool comes into contact with microroughnesses of the processed surface of the anode workpiece, the process of electrical erosion occurs, which is inherent in electric spark machining.

Products of electrical erosion and anodic dissolution are removed from the processing zone when the tool and workpiece move.

Electrical discharge machining is based on the laws of erosion (destruction) of electrodes made of conductive materials when a pulsed electric current is passed between them. It is used for stitching cavities and holes of any shape, cutting, grinding, engraving, sharpening and hardening tools. Depending on the parameters and type of pulses used to produce generators, electrical discharge machining is divided into electric spark, electric pulse and electric contact.

At a certain value of the potential difference on the electrodes, one of which is the workpiece being processed (anode), and the other is the tool (cathode), a conductivity channel is formed between the electrodes, through which a pulsed spark (electric spark processing) or arc (electric pulse processing) discharge passes. As a result, the temperature on the surface of the workpiece increases. At this temperature, an elementary volume of metal instantly melts and evaporates, and a hole is formed on the processed surface of the workpiece. The removed metal hardens in the form of small granules. The next current pulse breaks through the interelectrode gap where the distance between the electrodes is smallest. With continuous supply of pulsed current to the electrodes, the process of their erosion continues until all the metal located between the electrodes at a distance at which electrical breakdown is possible (0.01 - 0.05 mm) at a given voltage is removed. To continue the process, it is necessary to bring the electrodes closer to the specified distance. The electrodes are brought closer together automatically using a tracking device of one type or another.

Electric spark processing is used for the manufacture of stamps, molds, dies, cutting tools, parts of internal combustion engines, meshes and for strengthening the surface layer of parts.

Electrical contact processing is based on local heating of the workpiece at the point of contact with the electrode-tool and the removal of softened or molten metal from the processing zone by mechanical means (with relative movement of the workpiece and tool).

Electromechanical processing is associated primarily with the mechanical action of electric current. This is the basis, for example, of electrohydraulic processing, which uses the action of shock waves resulting from pulsed breakdown of a liquid medium.

Ultrasonic processing of metals - a type of mechanical processing - is based on the destruction of the material being processed by abrasive grains under the impacts of a tool oscillating at an ultrasonic frequency. The energy source is electrosonic current generators with a frequency of 16 - 30 kHz. The working tool - a punch - is fixed on the waveguide of the current generator. A workpiece is placed under the punch, and a suspension consisting of water and abrasive material enters the processing zone. The processing process consists of a tool oscillating at an ultrasonic frequency that strikes abrasive grains lying on the surface being processed, which chip away particles of the workpiece material.

FEDERAL AGENCY FOR EDUCATION

public educational institution
higher professional education

"ALTAI STATE UNIVERSITY"

"APPROVED"

Professor G.V. Lavrentiev

"____" ___________________ 2010

PROGRAM

advanced training of teaching staff

state educational institutions

primary vocational and secondary vocational education

in the priority area “Modern industrial technologies”

AGREED:

Vice-Rector for Quality

educational activities of G.A. Spitskaya

Director of the center Morozova

Barnaul 2010

^ I. INTRODUCTION

For the dynamic development of the main branches of technology, the creation of new mechanisms and machines, and the production of a wide range of consumer goods in Russia, dozens of new individual materials are created annually and formulations of hundreds of composites are developed. To process these materials into finished products used in various branches of technology and mechanical engineering, standard technological operations and standard equipment of specialized enterprises are used. However, often the properties of new materials, purposefully incorporated into them by materials scientists even during their creation, can significantly improve the economic, labor-intensive, energy and other indicators of technological processes for their processing, and, often, completely eliminate many standard operations or significantly reduce their time. Therefore, along with the process of creating new materials, work is constantly underway to adjust, improve and develop new processes and technologies for their processing.

Over the past 10-15 years, the number of such new technological processes has increased significantly, and their design has also changed - sometimes several hours pass from the stage of developing design drawings to the creation of a finished part in mass production. Both the style and content of the work of a mechanical design engineer, technologist, and machine operator have changed. If previously a significant share of the productive time of the first two was made up of routine design operations, work with reference literature, strength and technological calculations, development of drawings and technological maps, now numerous CAD and CAM systems successfully cope with this work. Until recently, a machine operator manually produced a part according to a developed technological map, sometimes moving the workpiece from one machine to another and using several types of tools, constantly monitoring process parameters and the dimensions of the finished part, but in modern production many technological operations of manufacturing and control are performed by automatic systems of universal machines and machining centers with computer numerical control (CNC).

Naturally, the successful use of new materials, equipment and technologies for processing structural materials in wide production is not possible without the mastery of them by personnel involved in training qualified specialists in the main production specialties - lathe, milling machine operator, general-purpose machine operator, etc. At the same time, the current state of equipment of training centers , professional lyceums and colleges with specialized and modern equipment, due to objective reasons, does not allow either the teachers and industrial training masters themselves or the students to master this knowledge and practical skills.

Currently, the issue of training specialists for mechanical engineering production equipped with CNC machines integrated into a single system with CAD/CAM systems used at a particular enterprise is, as a rule, resolved by the owner through paid retraining of workers in specialized training centers, the number of which is limited. Under these conditions, graduates of a vocational school find themselves uncompetitive, primarily due to the fact that the personnel teaching them do not themselves have the necessary qualifications. Of course, the issue of equipping educational institutions of scientific and vocational education and training with modern machines and systems for automated design of parts and design of technological processes for their processing cannot be resolved immediately, but this does not exclude the very possibility of training qualified training personnel for these institutions. Moreover, in the conditions of the current crisis situation, it is quite obvious that this kind of preparation should be proactive. For this purpose, in various regions of the Russian Federation, on a competitive basis, at the end of 2008 - beginning of 2009, resource centers were created, equipped with modern mechanical engineering equipment, CNC machines, CAD/CAM design systems, in which specialists of the professional school underwent retraining and advanced training .

This program was created by scientists from Altai State University with the participation of teachers from the Metalworking Center of BTI of Altai State Technical University and the Resource Center from Vocational School No. 8 in Barnaul.

The program is addressed to teachers of institutions of primary vocational and secondary vocational education and masters of industrial training who train qualified personnel in the secondary vocational education system in the following specialties:

0308 - Vocational training (by industry); 0309 – Technology; 1104 - Metallurgy and heat treatment of metals; 1105 - Metal forming; 1106 - Powder metallurgy, composite materials, coatings; 1201 - Mechanical engineering technology; 2101 - Automation of technological processes and production (by industry);

As well as workers in the NPO system in the following specialties:

011500 – Machine operator (metalworking); 011501 – General purpose machine operator; 011600 – Universal turner; 011700 – Universal milling machine; 010700 – Adjuster of machines and equipment in mechanical processing; 010703 – Installer of machine tools and manipulators with program control.

The course is based on the students' existing knowledge of the theory and practice of such disciplines as mechanical engineering technology, metalworking processes, machines and equipment of engineering enterprises, mathematics, physics and chemistry, computer science and programming, and materials science.

The goal of the program is to create conditions for students to successfully master modern industrial technologies for processing materials and structural materials as a subject of student training, a methodology for its organization and a means of optimizing the professional training of future specialists in the field of modern mechanical engineering.

Program objectives:

Formation of students’ ideas about the current state of mechanical engineering technology and the prospects for its development;

Familiarization with technological capabilities, equipment and promising methods of mechanical processing of structural materials;

Formation of holistic ideas about the basic patterns of shape formation, physical and chemical features of the processes of electrophysical and electrochemical processing;

Familiarization with the basic methods and methods of computer-aided design of parts and machining operations when using CNC machines based on CAD/CAM systems;

Formation of practical skills in working on machines with digital display devices and CNC, writing programs for them and manufacturing the simplest types of parts;

Formation among students of a holistic materials science approach to the process of selecting a product material, taking into account its consumer characteristics, structure and properties of structural materials, and their processing technologies;

Familiarization with progressive and low-waste technologies for obtaining materials and finished products based on powder metallurgy and SHS technologies;

Analysis of design, technological and operational requirements for new materials based on carbon, organic and inorganic (glass, quartz, basalt, etc.) fibers;

Formation of knowledge of operational properties in products of modern fibrous composite materials for various purposes and developed technologies for the production of products from them;

Familiarization with the possibilities and effectiveness of using materials in various fields of engineering and technology;

Formation of skills to apply physical methods of studying materials;

Formation of a competence-based approach to the studied material, its reflective processing and design of acquired knowledge, skills and abilities for individual professional activities.

The program is preceded by an invariant block that reveals and is designed to form in students an idea of ​​the leading trends in the development of domestic vocational education, to provide an understanding of the new priorities of state policy in this area, and knowledge of the regulatory framework of a modern vocational school.

The block “Trends in the development of modern mechanical engineering: new processes, equipment and materials” examines the main directions and priorities for the development of mechanical engineering in Russia, regulations that legislatively regulate the processes of technical and technological re-equipment of the mechanical engineering industry, the law on technical regulation and product quality, organization and principles of operation quality systems in mechanical engineering. Students will become familiar with the principles underlying most modern industrial technologies. The fundamental principles, design and technological features of new and advanced metal processing processes by cutting, plastic deformation, temperature, welding and exposure to high energies will be considered. Materials science of new structural materials will form the scientific basis of this block; based on knowledge about the properties of new structural materials and their changes in various technological processes, program participants will master the ability to choose the optimal technology for their processing to obtain parts with specified characteristics with minimal economic and energy costs, with a minimum quantity waste and a high level of process automation, will get acquainted with the properties of most modern steels and alloys, their processing modes and creation technology. This block will present the main types and brands of new technological equipment, machine tools and CNC machining centers, features of their design and operation. Students will acquire practical skills in designing parts and designing technological processes for their production in adapted CAD/CAM systems, gain an understanding of the basics of the modern process of high-tech design of parts, the organization and operating features of interactive design and technological systems, and learn to program basic standard operations for processing parts by cutting on machine tools. with CNC. At the same time, program participants will be provided with didactic material and simulation software products for independently organizing student training in the CAD and CAM design environment.

The “” block presents some of the most advanced technologies for producing finished products and materials with a minimum number of stages of mechanical and other processing - self-propagating high-temperature synthesis and production of products by pressing from metal and alloy powders. Students will become familiar with the theoretical foundations of SHS processes and their practical implementation, the main types of reactions used in industrial SHS technologies, the organization of production of powders of superhard compounds used as fillers for structural metal composites, SHS technologies for surface treatment, welding and soldering. During the course of mastering the block, students will gain practical skills in calculating the composition of a charge for carrying out the SHS process, a powder mixture for obtaining a steel blank or an alloy of a certain grade or a metal composite material with the required properties, organizing technological equipment for pressing powder material to obtain a finished product and blank, become familiar with with the peculiarities of organizing the SHS or powder process in a specific technology.

In the block “Polymer composite materials in modern mechanical engineering”, based on fundamental knowledge about the composition, structure and properties of polymer composite materials, students will become familiar with the principles of production and use of glass and carbon plastics in mechanical engineering. Here information will be presented on the areas of application and brands of specific polymer composite materials, the possibilities and prospects for replacing individual parts and assemblies made of metals and alloys with polymer composites, technologies for creating these materials and technologies for processing composites into finished products. Students will receive practical skills in designing a composite with specified properties and choosing the optimal technology for its production, skills in testing fiberglass and rod structures made from them and adjusting the technology for processing the material.

The logical conclusion of the program is the “block” in which students will be able to familiarize themselves with the practical and methodological implementation of the study of individual issues of the program and their application in their professional activities, and will become acquainted with the network of resource centers and collective use centers operating in Russia, existing both at state and at private enterprises, the characteristics and features of the equipment located in them, the conditions for the provision of educational services by these centers, as well as issues of internship and internship in these educational and scientific departments by small groups of specialists. Methodological issues of applying information technologies for their use in the professional activities of course participants will be considered, familiarization with existing freely distributed and demo versions of solid-state design systems, CAD/CAM systems, as well as various visualizers and simulators of machining operations and processing of parts on machines with CNC.

At the final stage of the courses, a round table will be held, at which students will make a presentation and defense of their certification work and will be able to exchange views on current issues in the methodology of the professional disciplines they teach and the inclusion of issues considered during the study of this program; it is also planned to publish its materials .

In the program, based on a synthesis of theoretical and practical components, using modern technological equipment of a machine-building enterprise, computer design systems and multimedia tools, interactive individual and group training of students in modern metalworking technologies on machines and CNC machining centers is carried out, as well as the formation of a competency-based approach in them the field of automatic design of parts and technological processes in CAD/CAM systems. During the training process, the main technological problems of modern mechanical engineering are solved, which consist in a reasonable choice of material for the manufacture of a specific part or device based on fundamental knowledge about the composition and properties of various materials and the ability to control them, the choice of technology for creating such a material, the development of optimal technology for its processing using modern highly automated machines and equipment, and carrying out the manufacturing process and final processing of the part with minimal human intervention.

During the implementation of the program, students will be presented with the achievements of scientists and teachers of Altai State University and Altai State Technical University in the scientific and educational fields in the field of modern mechanical engineering technologies and materials science of new materials, machine tools, educational equipment and methodological developments of the Altai Regional Resource Center for Metalworking, automated computer systems design of parts and technological processes for their production Adem, Keller interactive simulators for high-precision CNC machines HAAS, machines and equipment with digital display KGU NPO PU No. 8, etc., which will become the subject of their creative understanding and discussion.

The program is practice-oriented. Among the organizational forms of training, practical and laboratory classes predominate, during which students acquire practical skills in working with modern machine tools, designing in the environment of CAD/CAM systems, and programming CNC machines. During the implementation of the program, educational excursions will be held to industrial enterprises in Barnaul and Biysk (Biysk Fiberglass Plant LLC, Altai Center for Development, Anitim Research and Production Association OJSC), which use modern metalworking technologies and production and processing technologies in their activities polymer composites, as well as on the basis of the laboratories of the Center for Materials Science and the Center for Nanosciences, Nanotechnologies and Nanomaterials of Altai State University.

Training of students in the program “Materials Science and Modern Technologies for Processing Structural Materials” should provide:

– orientation of students in priority areas of development of modern professional education and mastering the skills of using student-oriented technologies in their professional activities;

– familiarization with modern technologies and equipment of machine-building enterprises;

– obtaining knowledge and practical skills for working on machines with DRO and CNC, designing parts and technological processing processes in the environment of CAD/CAM systems and applying them in practice;

– mastery of the basics of materials science of new structural materials, the methodology for their selection for the manufacture of specific machine parts and mechanisms within the framework of optimal technology.

A.V. Ishkov, Doctor of Engineering. sciences, prof. (supervisor); V.A. Plotnikov, Doctor of Physics and Mathematics. sciences, prof.; O.V. Startsev, Doctor of Engineering. sciences, prof.; V.N. Belyaev, Ph.D. tech. Sciences, Associate Professor

Implementation dates for the program “MATERIALS SCIENCE AND MODERN TECHNOLOGIES FOR PROCESSING STRUCTURAL MATERIALS”: March 15 – March 26, 2010

"APPROVED"

First Vice-Rector for Academic Affairs

Professor G.V. Lavrentiev

"______"_____________ 2010

^ CURRICULUM

Materials science and modern technologies for processing structural materials

Goal: professional development

^ Training period: 10-12 days

Full-time form of education

№
p/p

Total
hours

Including:

Forms
control

seminars, practical

laboratory

Modernization processes in vocational education in modern Russia

Trends in the development of modern mechanical engineering: new processes, equipment and materials in the activities of the future specialist

Industrial SHS technologies and powder metallurgy

protection of design assignments

Modern mechanical engineering technologies: problems of study in the educational process of a vocational school

round table

Director of the center Morozova

^ GOU VPO "ALTAI STATE UNIVERSITY"

"APPROVED"

First Vice-Rector for Academic Affairs

Professor G.V. Lavrentiev

"______"_____________ 2010

^ CURRICULUM PLAN

Materials science and modern technologies for processing structural materials

Goal: professional development

^ Training period: 10-12 days

Full-time form of education

Class schedule: from 6 to 8 hours a day

Name of sections, disciplines, topics

Total
hours

Including:

control

seminars,
practical

laboratory

Modernization processes in vocational education in modern Russia

Priorities of state educational policy in modern conditions

Legal acts on education: federal and regional problems of implementation

^ Trends in the development of modern mechanical engineering: new processes, equipment and materials in the activities of the future specialist

Current state and prospects for the development of mechanical engineering technology

Equipment and technologies for mechanical, electrical and physical-chemical processing of flat and three-dimensional parts

General principles for increasing efficiency and automation of metalworking

Quality assurance and certification of products, processes and mechanical engineering technologies

Plasma and laser cutting of sheet structural materials

Modern methods of continuous processing of metals by plastic deformation

Universal machines with digital display

HAAS machining centers

Development of technological processes for metal processing using CAD/CAM systems

Creation of control programs for processing parts on CNC machines

Manufacturing a part on a CNC machine

Industrial SHS technologies and powder metallurgy

Powder materials and products made from them

Interactions in systems of powder and powder-gas mixtures

Syntheses in powder mixtures diluted with an inert component

Synthesis of intermetallic and metal-ceramic structural materials

Polymer composite materials (PCM) in modern mechanical engineering

protection of design assignments

The role of PCM in modern mechanical engineering

Structure and properties of PCM

Technology, equipment and automation of PCM production processes

Mechanical processing of PCM parts

Methods and instruments for determining the complex of deformation-strength properties of PCM

PCM performance under real operating conditions

Modern mechanical engineering technologies: problems of study in the educational process of a vocational school

round table

Use of equipment of resource centers and shared use centers

Methodological aspects of the use of IT technologies in the educational process of training specialists in scientific and vocational education and training

Director of the center Morozova

^II. BIBLIOGRAPHY

Bushuev Yu.G., Persin M.I., Sokolov V.A. Carbon-carbon composite materials: Handbook. - M.: Publishing house Metallurgy, 1994.

Quality of machines: Handbook in 2 volumes / Ed. A.G. Suslova. - M.: Publishing house Mashinostroenie, 1995.

Composite materials: Handbook. / Under the general editorship. V.V. Vasilyeva and Yu.M. Tarnopolsky. –M.: Publishing house Mashinostroenie, 1990.

Computer-integrated production and CALS technologies in mechanical engineering / T.A. Alperovich, V.V. Barabanov, A.N. Davydov, etc. - M.: Publishing house of State Unitary Enterprise VIMI, 1999.

Kotler F. Fundamentals of Marketing. / Per. from English - M.: Publishing House Business Book, 1995.

Metalhead's Quick Guide. / Ed. A. E. Dreval, E. A. Skorokhodova. – M.: Publishing house Mashinostroenie, 2005.

Lakhtin Yu.M., Leontyeva V.P. Materials Science. – M.: Publishing House Mashinostroenie, 1990.

Libenson G.A. Production of powder products. Textbook for technical schools. - M.: Publishing house Metallurgy, 1990.

Lovygin A. Modern CNC machine and CAD/CAM system. - M.: Publishing house DMK, 2008.

Mechanical engineering: Encyclopedia. Manufacturing technology of machine parts. / Ed. A.G. Suslova. - M.: Publishing house Mashinostroenie, 1999.

Merzhanov A.G. Self-propagating high-temperature synthesis. Physical chemistry: Modern problems. –M.: Publishing House Chemistry, 1983.

Panov V.S. Technology and properties of sintered hard alloys and products made from them. Textbook for universities. - M.: MISIS Publishing House, 2001.

Perepechko I.I. Introduction to polymer physics. -M.: Publishing house Chemistry, 1978.

Rakovsky V.S., Saklinsky V.V. Powder metallurgy in mechanical engineering. –M.: Publishing house Mashinostroenie, 1973.

Lubricating and cooling technological means and their use in cutting: Directory / Under the general. ed. L.V. Khudobina. - M.: Publishing house Mashinostroenie, 2006.

Handbook of composite materials. In 2 volumes / Ed. J. Lubina. Per. from English -M.: Publishing house Mashinostroenie, 1988.

Skhirtladze A.G. Operator's work on computer-controlled machines: A textbook for prof. textbook establishments. - M.: Academy Publishing House, 1998.

Cutting theory. Textbook. / P.I. Yashcheritsyn et al. - M.: Publishing house New knowledge, 2006.

Mechanical engineering technology: In 2 volumes. Textbook for universities / V.M. Burtsev, A.S. Vasiliev, A.M. Dalsky and others - M.: Publishing house of MSTU im. N.E. Bauman, 1997.

Lathe - operator's manual (Russian). January 2007: Methodological manual. – Oxnard – California: Haas Automation Inc., 2007.

Feldshtein E.E. Processing of parts on CNC machines. Tutorial. - M.: Publishing house New knowledge, 2008.

Foteev N.K. Electrical discharge machining technology. - M.: Publishing house Mashinostroenie, 1980.

Milling machine - operator's manual (Russian). January 2007: Methodological manual. – Oxnard – California: Haas Automation Inc., 2007.

Chemistry of combustion synthesis. / Ed. M. Koizumi. Per. from Japanese –M.: Publishing House Mir, 1998.

Shishmarev V.Yu. Automation of technological processes. M.: Academia Publishing House, 2009.

^III. SUBJECTS OF FINAL CERTIFICATION WORKS

The current state of mechanical engineering in Russia and the CIS countries

New and low-waste technologies in mechanical engineering

American machine tool companies

"Smart" materials

Do traditional materials still have reserves?

Mechanical engineering in modern market conditions: pros and cons of CAD

Japanese machine tool companies

Market of metalworking machines in Russia and abroad

Modern metalworking technologies

Chinese machine tool companies

Mechanical engineering technologies of the future

Two alternative metalworking paths: metal removal and metal building

Determination of optimal cutting parameters

High-speed steels and tools

Nanodisplacements: their implementation and use in modern machine tools

Digital display device or CNC system?

Multi-axis CNC centers

Processing of standard parts on CNC machines

Bulgarian machine tool companies

Machine tool industry in modern Russia

Electrical discharge machining

Plasma and laser cutting

Waterjet machining: materials, features and applications

New steels and alloys for mechanical engineering

Low-waste metal processing technologies

Plastic deformation technologies and metal processing

Ceramics and metal-ceramics in modern mechanical engineering

Quality systems at Japanese engineering enterprises

Certification of quality management systems by specialized campaigns: step

Parts of machines, machine tools and instruments are manufactured using various methods: casting, pressure treatment (rolling, drawing, pressing, forging and stamping), welding and machining on metalworking machines.

Foundry. The essence of foundry production is that products or blanks of machine parts are obtained by pouring molten metal into molds. The resulting cast part is called a casting.

A- separate casting model, b - split core box, V - casting of a bushing with a gating system, G- rod.

The technological process of foundry production consists of preparing molding and core mixtures, making molds and cores, melting metal, assembling and pouring molds, removing castings from the mold and, in some cases, heat treating castings.

Casting is used for the manufacture of a wide variety of parts: beds of metal-cutting machines, cylinder blocks of cars, tractors, pistons, piston rings, heating radiators, etc.

Castings are made from cast iron, steel, copper, aluminum, magnesium and zinc alloys that have the necessary technological and technical properties. The most common material is cast iron - the cheapest material with high casting properties and a low melting point.

Shaped castings with increased strength and high impact toughness are made from carbon steel grades 15L, 35L, 45L, etc. The letter L means cast steel, and the numbers indicate the average carbon content in hundredths of a percent.

A casting mold, the cavity of which represents the imprint of the future casting, is obtained from the molding sand using a wooden or metal model.

As a material for molding; mixtures use used molding earth (burnt), fresh components - quartz sand, molding clay, modifying additives, binders (resins, liquid glass, etc.), plasticizers, disintegrants and others. Their choice depends on the geometry of the casting, its weight and wall thickness, and the chemical composition of the metal being poured.

Rods intended for producing cavities and holes in castings are made from the core mixture in special boxes.

The core mixture usually consists of low-clay sand and binders.

In individual and small-scale production, casting molds are made manually (molded), using wooden models, in mass production - on special machines (molding), on model plates (a metal plate with parts of the model firmly attached to it) and in two flasks.

Cast iron is melted in cupola furnaces (shaft furnaces), steel - in converters, arc and induction electric furnaces, and non-ferrous castings - in melting crucible furnaces. Metal melted in cupola furnaces is first poured into ladles and then through a gating system (a system of channels in a mold) into a mold.

After pouring and cooling, the casting is removed (knocking out) from the mold, the profits (feeders) are removed, and cleaned of burrs, remnants of the gating system and burnt earth.

Special casting methods. In addition to casting in earth molds, factories currently use the following progressive casting methods: casting in metal molds (moulds), centrifugal casting, pressure casting, precision investment casting, shell mold casting. These methods make it possible to obtain parts with a more precise shape and with small allowances for machining.

Casting into metal forms. This method consists of pouring molten metal not into a one-time earthen mold, but into a permanent metal mold made of cast iron, steel or other alloys. The metal mold can withstand from several hundred to tens of thousands of pours.

Centrifugalcasting. With this method, molten metal is poured into a rapidly rotating metal mold and, under the influence of centrifugal forces, is pressed against its walls. Metal is usually poured on machines with vertical, horizontal and inclined axis of rotation.

Centrifugal casting is used for the manufacture of bushings, rings, pipes, etc.

Castingunderpressure is a method of producing shaped castings in metal molds, in which metal is poured into the mold under forced pressure. In this way, small shaped thin-walled parts of cars, tractors, counting machines, etc. are produced. The materials for castings are copper, aluminum and zinc alloys.

Injection molding is performed on special machines.

AccurateLost wax casting. This method is based on the use of a model made from a mixture of easily melted materials - wax, paraffin and stearin. Casting is carried out as follows. Using a metal mold, a wax model is made with great precision, which is glued into blocks (herringbones) with a common gating system and lined with fire-resistant molding material. A mixture consisting of quartz sand, graphite, liquid glass and other components is used as a facing material. When the mold dries and fires, the facing layer forms a strong crust that gives an accurate impression of the wax model. After this, the wax model is melted and the mold is calcined. The molten metal is poured into the mold in the usual way. Precision casting is used to produce small shaped and complex parts for cars, bicycles, sewing machines, etc.

Castinginto shell forms is a type of casting in one-time earthen molds. A metal model of the future casting, heated to 220-250°C, is sprinkled from a hopper with a molding mixture consisting of fine quartz sand (90-95%) and thermosetting bakelite resin (10-5%). Under the influence of heat, the resin in the mixture layer in contact with the slab first melts, then hardens, forming a durable sand-resin shell on the model. After drying, the shell half-mold is combined with its corresponding other half-mold, resulting in a strong mold. Cork casting is used for casting steel and cast iron parts of machine tools, cars, motorcycles, etc.

The main defects of castings in foundry production are: warping - changes in the dimensions and contours of the casting under the influence of shrinkage stresses; gas cavities - voids located on the surface and inside of castings that arise from improper melting conditions; shrinkage cavities - closed or open voids in castings resulting from metal shrinkage during cooling.

Minor defects in castings are eliminated by welding with liquid metal, impregnation with thermosetting resins and heat treatment.

Metal forming. When processing metal by pressure, the plastic properties of metals are widely used, i.e. their ability, under certain conditions, under the influence of applied external forces, to change size and shape without destruction and to retain the resulting shape after the cessation of the forces. During pressure treatment, the structure and mechanical properties of the metal also change.

To increase the ductility of the metal and reduce the amount of work spent on deformation, the metal must be heated before pressure treatment. The metal is usually heated at a specific temperature depending on its chemical composition. For heating, furnaces, heating flame furnaces and electric heating units are used. Most of the processed metal is heated in chamber and methodical (continuous) gas-heated furnaces. Heating wells are used to heat large steel ingots arriving uncooled from steel smelting shops for rolling. Non-ferrous metals and alloys are heated in electric furnaces. Ferrous metals are heated in two ways: induction and contact. With the induction method, the workpieces are heated in an inductor (solenoid), through which a high-frequency current is passed, due to the heat generated under the influence of the induction current. In contact electric heating, a large current is passed through the heated workpiece. Heat is released as a result of the ohmic resistance of the heated workpiece.

Types of metal forming include rolling, drawing, pressing, open forging and stamping.

Rolling- the most widespread method of metal forming, carried out by passing metal into the gap between rolls rotating in different directions, as a result of which the cross-sectional area of ​​the original workpiece is reduced, and in some cases its profile changes. The rolling diagram is shown in Fig. 31.

Rolling produces not only finished products (rails, beams), but also long products of round, square, hexagonal profiles, pipes, etc. Rolling is carried out on blooming, slabs, section, sheet, pipe rolling and other mills, on smooth and calibrated rolls with streams (calibers) of a certain shape. On blooming machines, large and heavy ingots are rolled into square-section blanks called blooms, on slabs - rectangular-section blanks (steel disks), called slabs.

Section mills are used for rolling long and shaped profiles from blooms, sheet mills are used for sheet rolling from slabs in hot and cold conditions, and pipe rolling mills are used for rolling seamless (solid-drawn) pipes. Bandages, disc wheels, balls for bearings, gears, etc. are rolled on special-purpose mills

Drawing. This method consists of drawing cold metal through a hole (die) in a die, the cross-section of which is smaller than that of the workpiece being processed. During drawing, the cross-sectional area decreases, thereby increasing the length of the workpiece. Ferrous and non-ferrous metals and alloys in rods, wire and pipes are subjected to drawing. Drawing allows you to obtain materials with precise dimensions and high surface quality.

Segment keys and steel wire with a diameter of 0.1 mm, needles for medical syringes, etc.

Drawing is carried out on drawing mills. Drawing boards and dies made from tool steel and hard alloys are used as tools.

Pressing. It is carried out by pressing the metal through the hole in the matrix. The profile of the pressed metal corresponds to the configuration of the die hole, remaining constant along the entire length. Rods, pipes and various complex profiles are made by pressing from non-ferrous metals such as tin, lead, aluminum, copper, etc. They are usually pressed on hydraulic presses with a force of up to 15 thousand. T .

Forging. An operation in which metal is given the required external shape by blows of tools is called covewhoa. Forging carried out under flat dies is called free forging. , since the change in the shape of the metal with this type of processing is not limited to the walls of special shapes (dies) and the metal “flows” freely. Free forging can produce the heaviest forgings - up to 250 tons. Free forging is divided into manual and machine. Hand forging is mainly used in the manufacture of small items or for repair work. Machine forging is the main type of open forging. It is performed on forging pneumatic or steam-air hammers, less often - on forging hydraulic presses. In hand forging, the tools are an anvil, sledgehammer, chisel, punches, pliers, etc. In machine forging, the working tools are the strikers of forging hammers and presses, and the auxiliary tools are rolling pins, piercings and flares. In addition to auxiliary tools, machines called manipulators are used, designed to hold, move and tilt heavy workpieces during the forging process.

The main operations of the open forging technological process are: upsetting (reducing the height of the workpiece), drawing (lengthening the workpiece), piercing (making holes), cutting, welding, etc.

Stamping. The method of manufacturing products by pressure using stamps, i.e. metal forms, the outlines and shape of which correspond to the outline and shape of the products, is called stamping. There are three-dimensional and sheet stamping. In die forging, forgings are stamped on stamping and forging presses. The stamps consist of two parts, each of which has cavities (streams). The outlines of the streams correspond to the shape of the forging being produced. Forgings can also be stamped on single- and double-action steam-air hammers with a falling part (baba) weighing up to 20-30 tons and crank presses with a force of up to 10 thousand tons. During stamping, the heated workpiece under the action of the hammer blow is deformed and fills the die cavity, excess metal ( the flash) enters a special groove and is then cut off on the press. Small forgings are stamped from rods up to 1200 long mm, and large ones - from piece blanks.

Sheet stamping produces thin-walled parts from sheets and strips of various metals and alloys (washers, bearing cages, cabins, bodies, fenders and other parts of cars and devices). Sheet metal up to 10 thickness mm stamped without heating, more than 10 mm- with heating to forging temperatures.

Sheet metal stamping is usually carried out on crank and sheet metal stamping presses of single and double action.

In conditions of mass production of bearings, bolts, nuts and other parts, specialized forging machines are widely used. The horizontal forging machine is the most widely used.

BasicdefectsrentalAndforgings. When rolling blanks, the following defects may occur: cracks, hairlines, films, sunsets.

Cracks are formed due to insufficient heating of the metal or due to high compression in rolls.

hair appear on the surface of the rolled product in the form of elongated hair in those places of the metal where there were gas bubbles or cavities.

Captivity arise when rolling low-quality ingots.

Sunsets - these are defects like folds that result from improper rolling.

In forging and stamping production there may be the following types of defects: nicks, under-forging, misalignment, etc.

nicks, or dents, are simple damage to the forging that occurs when the workpiece is placed inaccurately in the die groove before the hammer strikes.

Understamping, or “undershooting” is an increase in height of the forging, which occurs due to an insufficient number of strong hammer blows or due to the cooling of the workpiece, as a result of which the metal loses its ductility.

Skew, or displacement, is a type of defect in which the upper half of the forging is displaced or warped relative to the lower.

Elimination of defects and defects is achieved by correct implementation of technological procedures esses of rolling, forging and stampingpovki.

Welding of metals. Welding is one of the most important technological processes used in all areas of industry. The essence of welding processes is to obtain a permanent connection of steel parts by local heating until melting or to a plastic state. In fusion welding, the metal is melted along the edges of the parts being joined, mixed in a liquid bath and solidified, forming a seam after cooling. When welding in a plastic state, the parts of the metal to be joined are heated to a softened state and combined into one whole under pressure. Depending on the types of energy used to heat the metal, chemical and electric welding are distinguished.

Chemicalwelding. In this type of welding, the heating source is the heat produced by chemical reactions. It is divided into thermite and gas welding.

Thermite welding is based on the use of thermite as a combustible material, which is a mechanical mixture of aluminum powder and iron scale, which develops a combustion temperature of up to 3000°C. This type of welding is used for welding tram rails, ends of electrical wires, steel shafts and other parts.

Gas welding is carried out by heating the metal with a flame of flammable gas burned in a stream of oxygen. Acetylene, hydrogen, natural gas, etc. are used as flammable gases in gas welding and metal cutting, but the most common is acetylene. The maximum temperature of the gas flame is 3100° C.

The equipment for gas welding is steel cylinders and welding torches with replaceable tips, and the material is structural low-carbon steel. A special welding wire is used as a filler material for welding steels.

Gas welding can be used to weld cast iron, non-ferrous metals, surfacing hard alloys, as well as oxygen cutting of metals.

Electricwelding. It is divided into arc and resistance welding. In arc welding, the energy required to heat and melt the metal is released by an electric arc, and in resistance electric welding, it is released by the passage of current through the part being welded.

Arc welding carried out on direct and alternating current. The heat source for this type of welding is an electric arc.

The welding arc is powered by direct current from welding machines-generators, alternating current - from welding transformers.

For arc welding, metal electrodes are used, coated with a special coating to protect the molten metal from oxygen and nitrogen in the air, and carbon electrodes.

Arc welding can be manual or automatic. Automatic welding is carried out using automatic welding machines. It ensures a high-quality weld and dramatically increases labor productivity.

Flux protection in this process allows you to increase the current strength without loss of metal and thereby increase productivity by five or more times compared to manual arc welding.

contact welding is based on the use of heat generated when an electric current passes through the part being welded. The parts to be welded at the point of contact are heated to a welding state, after which permanent connections are obtained under pressure.

Contact welding is divided into butt, spot and roller welding.

Butt welding is a type of resistance welding. It is used for welding rails, rods, tools, thin-walled pipes, etc.

Spot welding is done in the form of points in individual parts of the parts. It is widely used for welding sheet material of passenger car bodies, aircraft skins, railway cars, etc.

Roller, or seam, welding is carried out using roller electrodes connected to a welding transformer. It allows you to obtain a continuous and hermetically tight weld on sheet material. Roller welding is used for the manufacture of oil, gasoline and water tanks, and sheet steel pipes.

Defectswelding Defects that occur during welding can be lack of penetration, slag inclusions, cracks in the weld and base metal, warping, etc.

Metal cutting processing. The main purpose of such processing is to obtain the necessary geometric shapes, dimensional accuracy and surface finish specified in the drawing.

Excess layers of metal (allowances) are removed from the workpieces with a cutting tool on metal-cutting machines. Castings, forgings and billets from long rolled products of ferrous and non-ferrous metals are used as blanks.

Metal cutting is one of the most common methods of machining machine parts and devices. The processing of parts on metal-cutting machines is carried out as a result of the working movement of the workpiece being processed and the cutting tool, during which the tool removes chips from the surface of the workpiece.

Metal-cutting machines are divided into groups depending on processing methods, types and standard sizes.

Turningmachines are intended for performing a variety of turning operations: turning cylindrical, conical and shaped surfaces, boring holes, cutting threads with a cutter, as well as processing holes with countersinks and reamers.

Various types of cutting tools are used to work on lathes, but the main ones are turning cutters.

Drilling machines are used to make holes in workpieces, as well as for countersinking, reaming and tapping.

To work on drilling machines, cutting tools such as drills, countersinks, reamers and taps are used.

A drill is the main cutting tool.

A countersink is used to increase the diameter of pre-drilled holes.

Reamers are intended for making precise and finishing holes pre-processed with a drill or countersink.

Taps are used in the manufacture of internal threads.

Millingmachines are intended for performing a wide variety of work - from processing flat surfaces to processing various shapes. The tools used for milling are cutters.

Planingmachines used for processing flat and shaped surfaces, as well as for cutting straight grooves in parts. When working on planing machines, metal is removed only during the working stroke, since the reverse stroke is idle. The reverse speed is 1.5-3 times higher than the working speed. Metal planing is carried out with cutters.

Grindingmachines used for finishing operations that ensure high dimensional accuracy and quality of processed surfaces. Depending on the types of grinding, machines are divided into cylindrical grinding machines - for external grinding, internal grinding machines - for internal grinding and surface grinding machines - for grinding planes. The parts are polished with grinding wheels.

Undermetalworkingworks understand manual metal cutting. They are divided into basic, assembly and repair.

Basic metalworking work is carried out with the aim of giving the workpiece the shape, size, required cleanliness and accuracy specified in the drawing.

Assembly plumbing work is performed when assembling units from individual parts and assembling machines and instruments from individual units.

Mechanical repair work is carried out in order to extend the service life of metal-cutting machines, machines, forging hammers and other equipment. The essence of such work is to correct or replace worn and damaged parts.

Electrical methods of metal processing. These include electric spark and ultrasonic methods. The electric spark method of metal processing is used for making (piercing) holes of various shapes, removing broken taps, drills, pins, etc. from the holes of parts, as well as for sharpening carbide tools. Hard alloys, hardened steels and other hard materials that cannot be processed by conventional methods are processed.

This method is based on the phenomenon of electrical erosion, i.e., the destruction of metal under the influence of electric spark discharges.

The essence of the electric spark method of metal processing is that an electric current of a certain strength and voltage is supplied to the tool and product serving as electrodes. When the electrodes approach at a certain distance between them under the influence of electric current, a breakdown of this gap (gap) occurs. When a breakdown occurs, a high temperature arises, melting the metal and throwing it out in the form of liquid particles. If a positive voltage (anode) is applied to the workpiece, and a negative voltage (cathode) is applied to the tool, then during a spark discharge, the metal is pulled out of the workpiece. To prevent hot particles torn out of the workpiece electrode by the discharge from jumping onto the tool electrode and distorting it, the spark gap is filled with kerosene or oil.

The electrode tool is made of brass, copper-graphite mass and other materials. When making holes using the electric spark method, any contour can be obtained depending on the shape of the cathode tool.

In addition to the electric spark method of metal processing, industry uses an ultrasonic method based on the use of elastic vibrations of a medium with a supersonic frequency (vibration frequency more than 20 thousand. Hz). Ultrasonic machines can be used to process hard alloys, precious stones, hardened steel, etc.

For many decades, processing of non-ferrous metals has been very popular for the manufacture of various products. Technologies and modern production methods make it possible to speed up the process itself, as well as improve the quality of the final product.

They have a characteristic shade and high plasticity. Their extraction is carried out from the earth's rock, where they are found in very small quantities. Processing non-ferrous metals is a labor-intensive and financially demanding process, but it brings huge profits. Products made from them have unique characteristics that are not available when made from ferrous materials.

All non-ferrous metals are divided into several groups according to their properties:

• heavy (tin, zinc, lead);
• light (titanium, lithium, sodium, magnesium);
• minor (antimony, arsenic, mercury, cadmium);
• scattered (germanium, selenium, tellurium);
• precious (platinum, gold, silver);
• radioactive (plutonium, radium, uranium);
• refractory (vanadium, tungsten, chromium, manganese).

The choice of the group of non-ferrous metals used in production depends on the desired properties of the final product.

Basic properties

– a ductile metal with good thermal conductivity, but low electrical resistance. It has a golden color with a pink tint. It is rarely used independently; more often it is added to alloys. Metal is used to make instruments, machines, and electrical equipment.

- the most popular alloy with copper, produced by adding tin and chemicals. The resulting raw material has strength, flexibility, ductility, is easy to forge and is difficult to wear.

– conducts electricity well, belongs to ductile metals. It has a silver tint and is light in weight. Fragile, but resistant to corrosion. Used in military affairs, food industry and related industries.

- a rather brittle non-ferrous metal, but resistant to corrosion and ductile if heated to a temperature of 100–150 ºC. With its help, a corrosion-resistant coating is created on products, as well as various steel alloys.

When choosing a non-ferrous metal for a future part, you need to take into account its properties, know all the advantages and disadvantages, and also consider alloy options. This will allow you to create the highest quality product with the specified characteristics.

Using a protective coating

To preserve the original appearance and functionality of the product, as well as protect it from atmospheric corrosion, special coatings are used. Treating the product with paint or primer is the simplest and most effective method of protection.

To achieve a greater effect, apply a primer in 1–2 layers to the cleaned metal. This protects against destruction and helps the paint adhere better to the product. The choice of means depends on the type of non-ferrous metal.

Aluminum is treated with zinc-based primers or urethane paints. Brass, copper and bronze do not require additional processing. If damage occurs, polishing and application of epoxy or polyurethane varnish are carried out.

Methods of applying a protective layer

The choice of coating technique depends on the type of non-ferrous metal, the financing of the enterprise and the desired characteristics of the product.

The most popular method of processing non-ferrous metals to protect them from damage is electroplating. A protective layer of a special composition is applied to the surface of the product. Its thickness is adjusted depending on the temperature conditions at which the part will be operated. The harsher the climate, the larger the layer.

The galvanic method of processing parts in the construction of houses and cars is especially popular. There are several types of coating.

– carried out using chromium and alloys based on it. The part becomes shiny, the metal after processing is resistant to high temperatures, corrosion and wear. The method is especially popular in industrial production.

– is carried out using a current, the action of which causes the formation of a film when processing aluminum, magnesium and similar alloys. The final product is resistant to electricity, corrosion and water.

– carried out using a mixture of nickel and phosphorus (up to 12%). After coating, the parts are heat treated, which increases resistance to corrosion and wear.

The method of galvanic processing of parts is quite expensive, so its use for small industries is difficult.

Additional Methods

Spray metallization is a budget option. The molten mixture is applied to the surface of the product using an air jet.

There is also a hot method of applying a protective layer. The parts are immersed in a bath containing molten metal.

With the diffusion method, a protective layer is created under conditions of elevated temperature. Thus, the composition penetrates into the product, thereby increasing its resistance to external influences.

The application of another, more resistant metal to the non-ferrous metal from which the part is made is called cladding. The process involves casting, joint rolling, pressing and further forging of the product.

Modern processing technologies

There are several basic methods for processing non-ferrous metals. They are divided into several groups depending on technology and temperature conditions: hot and cold, mechanical and thermal.

The most popular of them:

• welding (chemical, gas, arc, electric, contact);