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[Abstract]: With the continuous development of economy and various technologies, the forging process has received more and more attention of the majority of people, and therefore it has become a technical discipline. Its rapid development has promoted the rapid development of China's machinery manufacturing industry. Therefore, in the future application of forging technology, relevant researchers must improve the research on the innovative application and development trend of forging technology in order to improve the application efficiency of forging technology and provide conditions for the further development of China's machinery manufacturing industry. This paper mainly discusses the application of various forging technologies and analyzes their application progress for reference in related research. [Keywords]: Forging technology; Classification; Development CLC number: TG31 1. Classification of forging technology Forging technology has the advantages of high production efficiency and strong forging comprehensive performance in the production and processing of machine tool parts. Therefore, it is widely used in machinery manufacturing. In recent years, with the further in-depth study of forging technology by related technical personnel, the application and classification of forging technology have become more and more sophisticated, which has a direct impetus to improving the application efficiency of forging technology. According to different production tools, forging technology can be divided into the following three. 1.1 Free forging This is a relatively simple forging technique. It mainly refers to the use of simpler tools for forging single or small batches of forgings. Forged forgings are relatively rough and are not suitable for use in precision mechanical equipment. However, this forging technique has higher forging efficiency and lower cost, and is suitable for forging a small number of workpieces; 1.2 Module forging As the name implies, this forging technique utilizes the impact of pre-prepared modules and related hammers and other tools to form the required size and shape of the billet in the module to achieve the purpose of forging. This kind of forging technique is relatively free forging and its cost is obviously increased. Therefore, it is often used in the production of large-volume forgings. 1.3 Special Forging For some special-performance machine tools, professional equipment and special forging techniques are required for forging purposes to achieve forging purposes. Special forging technology can only produce specific forgings, so it is more suitable for mass production of a certain type of forgings. 2. Progress of application of forging technology 2.1 Different forging techniques and their application First, isothermal forging technology: This technology is mainly applied to forging aluminum alloy forgings, and has the advantages of easy forging process control, simple forging process, low forging deformation speed, uniform structure, and improved anti-deformation ability. At the same time, for forging materials The use efficiency is also high, and it is a forging technique with good application effect. In the process of applying isothermal forging technology, it is necessary to strictly control the temperature of forging according to the requirements of forging, and a special mold heating device is added to ensure that the temperature is constant and the forging process proceeds smoothly. China's isothermal forging technology began in the 1980s and has reached a relatively mature level after several decades of development. At present, China's application of isothermal forging technology can forge different forgings and make the forgings have better organizational uniformity and structural stability. At the same time, it can effectively improve the application efficiency of forgings and save materials. Second, powder forging technology: This forging technology is mainly forging materials with powder as the main forging process of "powder-pressing-stripping-sintering-hot forging". After the above process, the dense forgings are finally formed. The application of powder forging technology has the advantages of full material utilization (utilization rate of 95% to 99%), high mechanical properties (it can effectively increase the internal density of forgings and further increase the rigidity of forgings, etc.), and the forgings have high precision (effectively controlling the size and performance of forgings Parameters, etc. to improve its accuracy) and so on. In addition, the powder forging technology has few application procedures and low cost, and is suitable for producing forged parts with complicated shapes and high performance requirements. At present, China's powder forging technology is mainly applied to forged gear parts, which can effectively improve the tooth root anti-fatigue strength and impact strength of gear forgings, and can also reduce the amount of gear processing and raw materials used, and the economic application of forging technology. The improvement of efficiency has a good promotion effect. Third, the discontinuous connecting rod forging technology: This forging technique is mainly applied to the forging of the connecting rod, and the technical requirements are relatively high. The technical personnel are required to strictly control the amount of vanadium, manganese and nitrogen added to ensure the toughness and elongation of the forging. Sex and antioxidant properties. Temperature control is also an important work. The temperature required for this forging technique is in the range of 1235°C±15°C. If the temperature is too high, the connecting rod will expand and break off the dross. If the temperature is too low, the tensile performance of the connecting rod will decrease. The problem is that the technological process of the discontinuous breaking rod forging technology is simplified and the number of processes is small. The forged connecting rod has a compact structure and high quality, and is a connecting rod forging technique with a high application effect. The difficulty in the application of the discontinuous connecting rod forging technique in China is to control various process parameters, such as heating temperature control (forging temperature directly affects the tensile strength of forgings) and decarburization layer control (does not allow full decarburization of forgings, most of which are The decarburization of the connecting rod shaft is about 0.2mm, the decarburization time is controlled within 12S, so that the decarburization is exceeded), and the cooling temperature is controlled (the control of cooling temperature and speed is mainly to control the precipitation of iron element in the forging, so that The iron content is up to the standard to ensure the strength of the forgings, etc. to ensure the forging quality. Fourth, crankshaft forging technology: The development of China's auto industry has increased the demand for crankshaft parts and also increased the requirements for crankshaft parts. In order to promote the development of the crankshaft processing industry, relevant technical personnel have increased the research on the crankshaft forging technology in order to be able to improve the forging efficiency and quality of the crankshaft parts and meet the development needs of China's automotive industry. The crankshaft forging technology is more complicated than other forging technologies. It requires a variety of more elaborate processes, such as heating by blanking, forging blanks and flattening, until pre-forging and final forging, and crankshaft forging is completed. Pre-production, after the need for forging parts trimming, twisting, adjusting accuracy and other processing, and finally through the straightening, stress relief, rust, inspection and other processes, in order to achieve the standard crankshaft parts, complete forging. When crankshaft forging technology is applied, the requirements for forging equipment are also high. With the development of science and technology, some forging factories have introduced computers to realize intelligent regulation and control, which has a good impetus for improving forging efficiency and quality. 2.2 Progress of Application of Forging Technology in China With the development of forging technology, various forging processes are thinking in the direction of more precise and innovative development, and their application effects are gradually improving. Mass production of a variety of different performance, shape, and size mechanical tool components has become possible. . First, precision module forging technology: This forging technology is proposed on the basis of common module forging technology. It is mainly to improve the precision of module forging to improve the precision and environmental protection of forgings. At present, there are three kinds of applications with good application prospects: flashless thermal module forging technology, flashless temperature module forging technology, and warm-to-cold compound forming forging technology. Due to different application conditions, the cost and performance of forged forgings are also different. There are slight differences. Second, forging technology of large-scale forgings: With the development of society and economy, the demand for large-scale mechanical equipment has gradually increased. Therefore, relevant technical personnel have proposed the forging technology of large forgings in light of this situation, that is, the size of the forgings. With the increase of the weight of the steel ingot size and weight, and focus on the ingot interior structure loose, holes and other problems to solve the strategy, in order to improve the effect of large forgings forging. In addition, during the development of forging technology, it is also necessary to optimize the calculation method of forging speed and the forming process to improve the application efficiency of forging technology. Third, multi-material forging technology: With the continuous emergence of various new materials, the raw materials that can be used for forgings are gradually increasing, which has an important role in promoting forging efficiency and quality, and promoting the strength of forgings. At present, the commonly used forging materials are mainly aluminum alloy materials, titanium alloy materials, magnesium alloys, etc. These alloy materials have the same important status as the precision forming of the alloy materials and the improvement of the quality of the forgings, and will be the future of forging. One of the main research questions in the process of technology development. 3. Conclusion In summary, this article briefly introduces several forging technologies and their application methods, and analyzes the application of forging technology, hoping to provide reference for relevant technical personnel to promote the application efficiency of forging technology in China. It is believed that with the constant deepening of research by technical personnel and the continuous development of related science and technology, forging technology will surely be developed more rapidly, and the application of precision forging technology will become more and more widespread, providing further development for the development of machinery manufacturing. Effective help.

Metal Forging Energy Saving Technology Research 1 Metal Forging Energy Consumption and Pollution Status 1.1 High energy consumption In the metal forging industry, the efficiency of energy use is limited by the work experience of practitioners, the thermal efficiency of materials, and the level of facilities. Energy waste is a serious phenomenon. The forging process mainly includes feeding, heating, forging, processing, and heat treatment. The heating process is the most energy-intensive process. According to statistics, the fuel consumption of the heating process accounts for about 75% of the entire process. At present, China's metal forging furnace technology is relatively backward, the average energy consumption per kilogram of forgings is about 20,000 kJ, and the average thermal efficiency is less than 5%. 1.2 Serious forging pollution The pollution generated during the forging process mainly includes pollution gas emissions, industrial waste discharge, and noise pollution. During the forging process, the combustion of materials generates a large amount of polluting gases. Some of the gases are discharged into the atmosphere without treatment, and carbon monoxide and sulphide pollution are the most serious. At the same time, carbon dioxide emissions will also exacerbate the greenhouse effect. The wastes discharged from metal forging mainly include waste oil, waste liquid and waste slag, including both coal residues after burning, fuel waste, and metal scraps and used machine lubricating oil. Some of the wastes have poor degradability and are polluted. Without adequate treatment, it will have a bad influence on the natural environment. Metal forging requires the use of many large-scale machinery. When the machine is in operation, it generates a lot of noise and affects the lives of surrounding residents. 2 Application of Energy Saving Technology in Metal Forging At present, the application of energy-saving technologies and energy-saving technologies in metal forging mainly includes the following three aspects. 2.1 Energy Saving Process and Equipment (1) Cold extrusion and cold forging: In the traditional metal forging process, the energy consumed by the heating and heat treatment process exceeds 75% of the entire process flow. In order to effectively save energy consumption, the cold forging process has emerged. The cold forging process is a forming process at a material recrystallization temperature, and forging is performed below the recovery temperature. At present, in many industries, such as automotive parts and some electronic equipment, cold forging technology has been promoted and applied. On the basis of further improvement of forging quality, the energy saving effect is very significant. See the following figure: Figure 1 Cold-forged lamp housing radiator (2) Isothermal forging: Isothermal forging is a plastic processing process in which a mold and a blank are heated to a forging temperature and then deformed at a low strain rate at this temperature. The deformation of isothermal forgings in the final forming stage is relatively slow, which is conducive to grasping the degree of deformation, so as to obtain a forging accuracy that is close to no excess, and significantly reduces the consumption of metal materials. (3) Reform of electro-hydraulic hammer: With the advancement of science and technology, the energy efficiency of the electro-hydraulic hammer has been greatly improved, and its energy efficiency has been increased to 15%-20%. At the same time, its driving power has been changed from boiler steam to electric drive. The dust pollution brought by the boiler's coal combustion has been reduced, and the environmental benefits have been improved. (4) Modification of the cooling water circulation system: When forging equipment, a large amount of cooling water is required in order to maintain the normal operation of the system. In particular, the IF furnace and the heat treatment furnace consume the most. Through the transformation of the cooling water circulation system, a regulating pool and a submersible pump are set up, and the cooling water in the forging process is cycled and used repeatedly, which can significantly reduce the waste of water resources. 2.2 Energy Saving of Process Flow (1) Energy-saving of production lines: The energy-saving of production lines mainly includes the following three aspects: First, the high-temperature exhaust gas is recycled, and the heat in the exhaust gas of the heating furnace is used in multiple stages in accordance with the temperature gradient. For example, the heating mold and the thermal insulation equipment can be used during isothermal forging. Heating furnace exhaust gas to achieve; second is the use of continuous casting and forging process, in the same set of molds, the first casting, casting immediately after completion of forging, so as to avoid the re-heating of the casting after cooling caused by energy waste; After the waste heat is used in the heat treatment process, the heating furnace is placed after the forging process, and the heat stored by the forging is fully utilized through such means as residual heat quenching, residual heat isothermal, and residual heat normalizing. (2) Energy saving in the forging process: scientific regulation of forging strength and forging sequence can effectively achieve energy saving. In the specific operation process, energy-saving process data can be inserted into the computer-aided process design system, and through system evaluation, the process flow with the lowest energy consumption and cost can be found to achieve energy-saving production. as shown in picture 2 . 2.3 production scheduling energy Production scheduling is the process of rationally deploying workpieces that are waiting to be processed, as well as production lines and machines, and arranging the order in which the workpieces are produced by the machine. Reasonable allocation of production system resources can optimize production indicators, increase work efficiency, and reduce resource waste. In metal forging, the production scheduling can be optimized mainly from three aspects. The first one is forging furnace. Mainly through the rational distribution of forging materials, increase the use of heating furnace; Second, forgings out of the furnace. Mainly by reducing the holding time, reducing the number of open furnace and other methods, do a good job forgings forging and forgings between the forging of the connection; three forgings forging. Take full account of the forging steps and the materials and time required for each stage to minimize waiting time for forging equipment. See below: 3 Conclusion Metal forging is the cornerstone of heavy industry development, and the current metal forging industry still has a lot of room for improvement. This paper analyzes the current status of metal forging and focuses on the application of energy-saving technologies. It hopes to help promote the popularization of energy-saving optimization technologies in various industrial production industries.

Imperfections caused by improper forging process Large grain Large grains are usually caused by high initial forging temperatures and insufficient deformation, or high final forging temperatures, or deformation levels that fall into critical deformation zones. The degree of deformation of the aluminum alloy is too large to form a texture; the deformation temperature of the high-temperature alloy is too low, and coarse grains may also be caused when a mixed deformed structure is formed. The coarseness of the crystal grain will reduce the plasticity and toughness of the forging, and the fatigue performance will obviously decrease. 2. Non-uniform grain Non-uniform grain refers to the fact that the crystal grains in some parts of the forging are particularly thick and some parts are smaller. The main cause of grain non-uniformity is that the uneven deformation of the billet causes the grain to be broken to varying degrees, or the deformation of the local area falls into the critical deformation zone, or the local processing and hardening of the superalloy, or the local grain during quenching and heating. Thick. Heat-resistant steels and superalloys are particularly sensitive to grain inhomogeneities. Non-uniform grain will significantly reduce the permanent properties and fatigue properties of forgings. 3. Chilling phenomenon Deformation due to low temperature or deformation speed is too fast, and cooling too fast after forging, may cause the softening caused by recrystallization can not keep up with the deformation caused by hardening, so that the forgings after hot forging still retain some of the cold deformation of the organization. The presence of this structure increases the strength and hardness of the forgings, but reduces the plasticity and toughness. Severe chilling may cause cracking. 4. Crack Cracks are usually caused by large tensile stress, shear stress, or additional tensile stress during forging. The location where cracks occur is usually at the location where the billet has the greatest stress and the thinnest thickness. If there is micro-cracks on the surface and inside of the billet, or there are structural defects in the billet, or if the thermal processing temperature is not appropriate, the plasticity of the material is reduced, or the deformation speed is too fast, the deformation degree is too large, and the plasticity pointer beyond the material is allowed to be removed, Cracks may occur in the process of drawing, punching, reaming, bending, and squeezing. 5. Cracking Cracking presents shallow, crack-like cracks on the surface of the forging. Surfaces that are subject to tensile stress during forging forming (eg, underfilled or bent portions) are most likely to cause such defects. The internal causes of cracking may be numerous: 1) The raw materials are too many fusible elements such as Cu and Sn. 2) When heated at high temperature for a long period of time, the surface of the steel material is precipitated with copper, coarse grains on the surface, decarburization, or surfaces that have been heated many times. 3) The sulphur content of the fuel is too high and sulfur penetrates the surface of the steel material. 6. Flying edge crack The flash crack is a crack that occurs at the parting surface when die forging and trimming. The reason for the crack in the flash may be: 1) The threading phenomenon occurs due to the strong flow of metal due to a heavy blow in the swaging operation. 2) The trimming temperature of magnesium alloy die forgings is too low; the cut temperature of copper alloy die forgings is too high. 7. Split surface crack Parting surface cracking refers to cracking along the die parting surface of a forging. There are many non-metallic inclusions in the raw material, flow to the parting surface during die forging and residual or shrinkage tube residuals often form cracks on the parting surface after crowding the flashes during die forging. 8. Fold Folding occurs when the oxidized superficial layers of metal are brought together during metal deformation. It may be formed by the confluence of two or more strands of metal convection; it may also be caused by the rapid and massive flow of one metal, which involves the confluence of the surface metal of the adjacent parts, and the confluence of the two; or it may be due to deformation. The metal is bent and reflowed; it is also possible that some of the metal is locally deformed and pressed into another part of the metal. The folding is related to the shape of the raw material and the blank, the design of the mold, the arrangement of the forming process, the lubrication conditions, and the actual operation of the forging. Folding not only reduces the load-bearing area of the part, but it also tends to be a source of fatigue due to stress concentration at work. 9. Through the flow Through-flow is a form of improper distribution of streamlines. In the flow zone, the flow lines originally distributed at an angle merge to form a flow, and the size of the grains in the flow zone can be quite different. The reason for the flow through is similar to that of folding. It is formed by two metals or one metal with another metal confluence, but the metal in the flow-through part is still a whole, and the through-flow causes the mechanical properties of the forging to decrease, especially When the crystal grains on the two sides of the flow zone are different from each other, the performance is significantly reduced. 10. Forging flow distribution is not smooth The unfavorable distribution of the flow lines of the forgings means that the streamline cutting, backflow, eddy currents and other streamline disturbances occur at a low magnification of the forgings. If the mold design is not proper or the forging method is not selected properly, the streamline of the preform is disordered; the improper flow of the metal due to the improper operation of the worker and the wear of the mold can make the streamline distribution of the forging unfavorable. Disadvantages in flow lines can cause various mechanical properties to be reduced. Therefore, flow distribution is required for important forgings. 11. Foundry tissue residue Casting tissue residues mainly occur in forgings with ingots as a blank. The as-cast microstructure mainly remains in the hard deformed area of the forging. Insufficient forging ratio and improper forging method are the main reasons for the formation of residual cast tissue. Casting tissue residue can degrade the properties of the forgings, especially the impact toughness and fatigue properties. 12. Carbide segregation level does not meet the requirements The level of carbide segregation does not meet the requirements mainly in the Layman tool steel. The carbides in the forgings are mainly distributed unevenly, and are distributed in a large block or distributed in a network. The main cause of this defect is the poor level of segregation of carbides in raw materials, combined with inadequate forging ratio during forging, or improper forging methods. Forgings with this type of defects are easily overheated and quenched during heat treatment and quenching, resulting in cutting tools and dies. Easy to use when broken. Illustration: Cracks evolved and precipitated carbides 13. Ribbon organization The banded structure is a kind of organization in which ferrite and pearlite, ferrite and austenite, ferrite and bainite, and ferrite and martensite are distributed in strips in forgings. Asiatic steel, austenitic steel and semi-martensite steel. This kind of organization is the banded structure produced when forging deformation in the coexistence of two phases can reduce the material's transverse plasticity index, especially the impact toughness. When forging or parts work, it is often easy to crack along the boundary of ferrite or two phases. 14. Insufficient local filling Insufficient local filling mainly occurs in ribs, lobes, corners, and rounded corners, and the dimensions do not meet the pattern requirements. The reason may be: 1) Low forging temperature and poor metal flow. 2) The tonnage of the equipment is not enough or the hammering force is insufficient. 3) The blank mold design is unreasonable, and the blank volume or cross-section size is not qualified. 4) Stack oxide or weld deformed metal in the mold. 15. Undervoltage Underpressure is generally increased in dimension perpendicular to the parting plane. The reason for this may be: 1 Low forging temperature. 2 Insufficient tonnage of equipment, insufficient hammering force or insufficient number of hammer blows. 16. Misalignment Misalignment is the displacement of the forging along the upper half of the parting surface relative to the lower half. The reason may be: 1) The gap between the slider (hammer head) and the guide rail is too large. 2) The design of the forging die is irrational, and there is a lack of locks or guide pillars to eliminate misalignment forces. 3) Poor mold installation. 17. Axis bending Forging axis bending, and the geometric position of the plane error. The reason may be: 1) The forgings do not pay attention when they are ejected. 2) Uneven stress when trimming. 3) The cooling rate of various parts during cooling is different. 4) Improper cleaning and heat treatment.

Precision Forging Process Editing There are many precision forging processes that have been applied to production. According to the different forming temperature can be divided into hot precision forging, cold precision forging, warm precision forging, composite precision forging, isothermal precision forging and so on. Hot forging process The precise forging process with the forging temperature above the recrystallization temperature is called hot forging. The hot precision forging material has low deformation resistance and good plasticity, and it is easy to form a relatively complicated workpiece. However, because of strong oxidation, the workpiece surface quality and dimensional accuracy are low. Hot forging commonly used process is closed die forging. Cold forging process Cold forging is a precision forging process performed at room temperature. The cold precision forging process has the following characteristics: the shape and size of the workpiece can be easily controlled to avoid the error caused by high temperature; the strength and accuracy of the workpiece are high, and the surface quality is good. Cold forging forming process towel, the workpiece is poor in plasticity, deformation resistance, mold and equipment requirements, and it is difficult to form complex parts. Precision forging process Warm forging is a precision forging process performed at a suitable temperature below the recrystallization temperature. Warm forging precision forming technology not only overcomes the limitation of large deformation resistance in cold forging forming, the shape of parts can not be too complex, the need of intermediate heat treatment and surface treatment step, but also overcomes the decrease of surface quality and size due to strong oxidation in hot forging. The problem of accuracy. It also has the advantages of cold forging and hot forging, overcoming the disadvantages of both. Composite forging process With the increasing complexity of precision-forged workpieces and increased precision requirements, simple cold, warm, hot forging processes can no longer meet the requirements. The composite precision forging process sews cold, overflow, and hot forging processes to complete the forging of a workpiece, and can exert the advantages of cold, warm, and hot forging, eliminating the disadvantages of cold, warm, and hot forging. Isothermal precision forging process Isothermal precision forging means that the billet is forged at a constant temperature. Isothermal die forging is commonly used in the aerospace industry for precision forming of difficult-to-deform materials such as titanium alloys, aluminum alloys, and magnesium alloys. In recent years, it has also been used in the precision forming of non-ferrous metals in the automotive and machinery industries. Isothermal forging is mainly used for metal materials with a narrow forging temperature, especially titanium alloys that are very sensitive to deformation temperature.

The difference between casting, forging, stamping, and casting (1) Casting is the melting of the raw material to allow it to naturally form in the forming mold. Forging is to heat the raw material to a certain temperature and then use the tool to forge the forming. Stamping is to stamp the raw material with a suitable stamping die. Die Casting is to use pressure on the basis of casting The melted material is poured into the mold to give it a higher density or a more precise shape. Casting: The molten liquid metal fills the cavity to cool. Porosity is easily generated in the middle of the parts. (2) Forging: It is mainly formed by extrusion at a high temperature. The grains in the part can be refined. The thickness of the part is basically equivalent to the stamping used for forming the sheet. The thickness of the parts is very different, the shape is complex, not hot, and die-casting is used. 1. Casting is divided into two types: high pressure casting and low pressure casting. To put it simply, after the metal is melted, the pressure is not the same as the pressure of the model, and the temperature of the heated metal is not the same as the machine used for casting. 2, forging is also a way of casting, the difference is that the temperature at the time of forging is lower, and some can be made of metal in semi-molten state. (3) Stamping is a process in which a semi-finished product is made into a finished product with a punch press and the like at room temperature. 4, die casting is also a way of high temperature casting, when the structure is more complex, more difficult castings, you can use the die casting machine, the metal is heated to a liquid state, pressed into the mold, cooling the mold to open the product after removal Casting method.

Forging part the main method of forming is free forging and mould forging. Mould forging is the main forging forming process, the equipment used mainly forging hammer, anvil-free hammer, crank press, screw press and high-speed hammer and so on. Forging high productivity, forgings size stability, high material utilization, it is widely used in small and medium-sized forgings mass and mass production. Automotive, tractors, aircraft, power machinery and other industries, it is estimated that a large number of die forging, forging the total weight of these industries for about 90%. Free forging is a simple and flexible metal forming method, although free forging is considered to be an outdated and uneconomical method of forging for small and medium-sized forgings in mass or bits production, but for small batches or units , Especially large forgings, are freely forged on hammers or hydraulics but are still an affordable and economical method of production. Forging and forming In addition to free forging and a variety of basic methods of forging, there are some other special forming methods, such as electric upsetting, cold extrusion, rotary forging, roll forging, swing rolling, multi-hammer forging, magnetic forging, Plastic forming, hydroforming, suspension forging, etc., developed rapidly at home and abroad nearly two decades. This special forging forming technology, will effectively promote the rapid development of the material processing industry.

With the development of forging technology, all kinds of forging processes are developing in a more precise and innovative direction, and their application effect is also gradually improving. Mass production of various machine tools and components with different performance, shape and size has become possible. First, precision module forging technology: This forging technology is put forward on the basis of common modular forging technology, it mainly improves the accuracy of module forging, so as to improve precision and environmental protection of forging. At present, the application prospect is better, that is, no flex hot module forging technology, no flex temperature module forging technology and warm and cold composite forming and forging technology. Because of the different application conditions, the forging cost and performance of the three parts are also slightly different. Second, the forging technology of Large Forgings: with the development of social and economic construction, the demand for large mechanical equipment gradually increased, therefore, the relevant technical personnel in such cases, the forging technology of large forgings is proposed, according to the size and weight of forging to improve the size and the weight of steel ingot, and focuses on the interior structure the loose and holes to resolve the problems such as strategy, in order to improve the effect of forging of large forgings. In addition, during the development of forging technology, we need to optimize the forging speed calculation and forming process, so as to improve the application efficiency of forging technology. Third, multicomponent forging technology: with the continuous emergence of various new materials, the materials that can be selected for forging can also increase gradually, which will play an important role in improving the efficiency and quality of forging and improving the strength of forgings. At present, more commonly used materials are the main Aluminum Alloy forging materials, titanium alloy, magnesium alloy, the alloy material of the multi scale precision forming and forging quality improvement, forging processing methods are of equal importance, will be the future of forging technology development process, is one of the main research problems.

Forging is one of the two major components of forging (forging and stamping) that utilizes a forging machine to apply pressure to a metal blank to cause it to plastically deform to achieve mechanical properties, a processing method of a certain shape and size forgings. By forging can eliminate the metal in the smelting process resulting loose castings and other defects, optimize the microstructure, at the same time due to save the integrity of the metal streamline, the mechanical properties of forgings generally better than the same material castings. Related machinery, high load, the working conditions of critical parts, in addition to the shape of the more available rolled sheet, profile or welded parts, the use of more forgings. 1. Deformation temperature The recrystallization temperature of the steel is about 727 ° C, but 800 ° C is commonly used as the dividing line, hot forging above 800 ° C, warm forging or semi-hot forging between 300 and 800 ° C, forging at room temperature Called cold forging. Used in most industries are forging hot forging, warm forging and cold forging is mainly used for automotive, general machinery and other parts forging, warm forging and cold forging can be effective materials. Forging category Mentioned above, according to forging temperature, can be divided into hot forging, warm forging and cold forging. According to forming mechanism, forging can be divided into free forging, forging, rolling ring, special forging. 1) free forging. Refers to the use of simple tools, or forging equipment between the upper and lower anvil directly to the blanks exert an external force, so that deformation of the blank to obtain the desired geometry and internal quality forgings processing methods. Forgings produced by free-forging methods are called free forgings. Free forging is based on the production of small quantities of forgings, using forging hammer, hydraulic forging equipment for forming the blank to obtain qualified forgings. Free forging basic processes include upsetting, drawing, punching, cutting, bending, twisting, misalignment and forging and so on. Free forging are hot forging method. 2) forging. Forging is divided into open forging and closed forging. Metal billet in forging die with a certain shape of the cavity obtained by forging, die forging generally used for the production of small weight, large quantities of parts. Forging can be divided into hot forging, warm forging and cold forging. Warm forging and cold forging is the future direction of forging, but also represents the level of forging technology. According to the material points, forging can also be divided into black metal forging, non-ferrous metal forging and powder products forming. As the name suggests, is the material is carbon steel and other ferrous metals, copper and aluminum and other non-ferrous metals and powder metallurgy materials. Extrusion should be attributed to forging, can be divided into heavy metal extrusion and light metal extrusion. Closed forging and upsetting are two types of advanced forging process, because there is no flash, the material utilization rate is high. With a process or a few processes may be completed complex forging finishing. As there is no flash, the forging area decreases, the required load is also reduced. However, care should be taken not to limit the billet to a full extent, for which purpose the billet size should be carefully controlled, the relative position of the forging die controlled and the forgings measured, in an effort to reduce die wear. 3) Rings. Rings refers to the production of rings of different diameters by special equipment Rings ring parts, but also used to produce wheel hubs, train wheels and other wheel parts. 4) special forging. Special forging, including forging, cross wedge rolling, radial forging, liquid forging and other forging methods, these methods are more suitable for the production of certain special shapes of parts. For example, roll forging can be used as an effective preforming process to drastically reduce subsequent forming pressures; cross wedge rolling produces parts such as steel balls and shafts; and radial forging produces large forgings such as barrel and step shafts. 5) Forging die According to the forging die movement, forging can be divided into the roller, swivel forging, roller forging, wedge cross rolling, rolling ring and oblique rolling and other means. Rolling, swaging and rolling rings can also be used for precision machining. In order to improve the utilization of materials, roll forging and cross-rolling can be used as slender material before the process of processing. Rotary forging, as with free forging, is also partially formed and has the advantage of being formed in a less forged condition compared to forgings. Including free forging, including this forging method, the processing of materials from the mold surface to the free surface near the expansion, it is difficult to ensure the accuracy, therefore, the direction of the forging die and swaging process using computer control, you can use the lower Forging force to obtain complex shape, high precision products, such as the production of many varieties, large size turbine blades and other forgings. Forging equipment, mold movement and degree of freedom are inconsistent, according to the characteristics of the bottom dead center deformation, forging equipment can be divided into the following four forms: Forging force in the form of restrictions: direct drive hydraulic block hydraulic press. Quasi-stroke limiting method: hydraulic drive crankshaft linkage hydraulic machine. Stroke limitation: Mechanical presses with cranks, connecting rods and wedge drive sliders. Energy limitation: Spiral and friction presses using a screw mechanism. In order to obtain high accuracy, care should be taken to prevent overload at bottom dead center, control of speed and die position. Because these will forgings tolerance, shape accuracy and die life have an impact. In addition, in order to maintain accuracy, care should be taken to adjust the slider rail clearance, to ensure rigidity, adjust the bottom dead center and the use of subsidies for transmission and other measures. There are also vertical and horizontal movement of the slider (used for forging of slender parts, lubrication cooling and high-speed production of parts forging). The compensation device can increase the movement in other directions. The above methods are different, the required forging force, process, material utilization, yield, dimensional tolerances and lubrication cooling are not the same, these factors are also factors that affect the level of automation. Forging timber Forging materials are mainly various components of carbon steel and alloy steel, followed by aluminum, magnesium, copper, titanium and its alloys. The raw materials are bar, ingot, metal powder and liquid metal. Metal deformation in the cross-sectional area and the deformation of the cross-sectional area ratio called the forging ratio. Correct choice of forging ratio, reasonable heating temperature and holding time, a reasonable forging temperature and final forging temperature, a reasonable amount of deformation and deformation speed to improve product quality, reduce costs have a great relationship. Small and medium-sized forgings are generally round or square bar as a blank. Bar material grain and mechanical properties of uniform, good, accurate shape and size, surface quality, ease of mass production organizations. As long as the reasonable control of the heating temperature and deformation conditions, without the need for large forging deformation will be able to forge a good performance forgings. Ingots are used for large forgings only. Ingots are as-cast, with larger columnar crystals and loose centers. Therefore, it is necessary to break the columnar grains into fine grains through large plastic deformation, and to loosely compaction to obtain excellent metallic structure and mechanical properties. The pressed and sintered powder metallurgy preform, in the hot state without flash die forging can be made of powder forgings. Forging powder close to the density of the general forging, with good mechanical properties, and high precision, can reduce the follow-up of cutting. Powder forging internal organization uniform, no segregation, can be used to manufacture small gears and other parts. However, the price of powder is much higher than the price of the general bar, the application of the production is subject to certain restrictions. Applying static pressure to the liquid metal poured into the mold cavity, allowing it to solidify, crystallize, flow, plastically deform and form under pressure to obtain the forging with the desired shape and properties. Liquid metal forging is between die-casting and forging between the forming method, especially suitable for general forging difficult to form complex thin-walled parts. Forging materials in addition to the usual materials, such as various components of carbon steel and alloy steel, followed by aluminum, magnesium, copper, titanium and its alloys, the iron-based superalloy, nickel-based superalloy, cobalt-based superalloy Of the deformation alloy is also used forging or rolling to complete, but these alloys because of its plastic zone is relatively narrow, so the difficulty of forging will be relatively large, heating temperature of different materials, forging temperature and final forging temperature have strict requirements. 4, process Different forging methods have different processes, of which the hot-forging process is the longest, the general order of: forging blanking; forging billet heating; forging blank billet forging; trimming; punching; correction; Intermediate inspection, testing forgings size and surface defects; Forging heat treatment, to eliminate forging stress, improve metal cutting performance; Clean up, the main surface is to remove the oxide coating; Correction; inspection, the general forgings to go through the appearance and hardness inspection, To go through chemical composition analysis, mechanical properties, residual stress testing and non-destructive testing. 5, forging characteristics Compared with the castings, the metal after forging process can improve its structure and mechanical properties. Casting organizations after forging deformation after hot deformation due to metal deformation and recrystallization, so that the original coarse dendrites and columnar grains into smaller grains, uniform size equiaxed recrystallization, the original segregation within the ingot, Loose, porosity, slag and other compaction and welding, the organization has become more closely and improve the metal's plasticity and mechanical properties. The mechanical properties of castings are lower than those of forgings of the same material. In addition, the forging process can ensure the continuity of the metal fiber organization, make the forging fiber organization and the forging appearance consistent, the metal streamline is complete, can ensure the parts have good mechanical properties and long service life. With precision forging, cold extrusion , Warm extrusion and other production forgings, are castings can not match Forgings are articles in which the metal is pressured to shape the desired shape or suitable compression force by plastic deformation. This force is typically achieved by using a hammer or pressure. The forging process builds a fine grain structure and improves the physical properties of the metal. In the actual use of components, a correct design allows particles to flow in the direction of the main pressure. Casting is a metal molding obtained by various casting methods, that is, smelting a good liquid metal, pouring, injection, suction or other casting methods into a pre-prepared mold, after cooling through the sand, cleaning and after Treatment, etc., the resulting shape with a certain size and performance of the object.

Features In the forging hammer or press with a forging die metal forging process for forming. Forging process of high production efficiency, low labor intensity, size accuracy, small allowance, and the forging of complex shapes forgings; suitable for mass production. However, the high cost of mold, the need for a dedicated forging equipment, not suitable for single or small batch production. 1 Because of the flow of mold-guided metal, the shape of the forgings can be complex. 2 forging internal forging streamline distribution by forging profile, thereby enhancing the mechanical properties of parts and service life. 3 simple, easy to mechanize, high productivity. Collapse edit this section categories According to the different equipment, die forging into hammer forging, crank press forging, forging die forging, friction press forging. The equipment used for the forging on the hammer is a forging hammer, usually an air forging hammer. Forgings of complex shape are first formed in a mold cavity and then forged in a forging cavity. According to the forging die structure classification: Forging die has to accommodate the excess metal burr groove, known as open forging; the other hand, the forging die does not accommodate the excess metal burrs, known as closed forging. Directly molded from the original billet, known as single-die forging. For the complex shape of the forging, in the same forging die through a number of steps required pre-formed, known as multi-die forging. Precision forging is developed on the basis of forging, forging some complex shapes, high precision parts, such as: bevel gears, blades, aviation parts. Collapse edit this section preparation Forging forging die, up and down by the two modules, the die 4 is the working part of the die, the upper and lower die half. With dovetail and wedge 1,2 fixed on the hammer anvil and the workbench; and 3 to guide the lock or guide to prevent the upper and lower module dislocation. Metal blank according to the shape of the mold cavity deformation. Forging process for the blank, pre-forging and final forging. Final forging die cavity is forgings size, shape, plus margin and deviation to determine. Die forging is generally divided into two kinds of die forging and die forging two types: open die forging the mold around the burr 5, forming excess metal flow into the tank, and finally cut the burr; closed die forging only at the end of a very small Of the burr, if the blank is accurate, you can not flash.

Free forging is to heat a good metal billets on the forging equipment, the next between the iron, the impact or pressure, the billet directly produce plastic deformation, so as to obtain a required forgings Processing Method Free Forging Because of the simple shape and flexible operation, it is suitable for the production of single piece, small batch and heavy forgings.Free forging manual free forging and machine free forging.Free hand forging has low production efficiency and labor intensity, In the repair or simple, small, small batch forgings, in modern industrial production, the machine has become a free forging the main method of forging production, heavy machinery manufacturing, it has a particularly important role.Forging forging the full name of the model forging, The heated blank is placed in a forging formed in a forging die secured to a forging apparatus. Forging can be carried out on a variety of devices. In industrial production, hammer forging mostly use steam - air hammer, tonnage in the 5KN ~ 300KN (0.5 ~ 30t). Die forging press commonly used hot die forging presses, tonnage 25000KN ~ 63000KN. Die forging die structure with single-mode forging die and multi-die forging die. As shown in Figure 3-13 single-mode forging die, which uses dovetail and wedge with the forging die fixed to prevent the prolapse and move around; with the key and the keyway forging die positioning accuracy, and to prevent the move back and forth. Single-chamber bore is generally forging die, forging air hammer often need to blank, and then through the final forging hammer multiple hammering once formed, and finally remove the forging removal of the flash.

(1) Casting: The non-shape of the liquid metal into a solid shape. Forging: A solid that turns one shape solid into another. Casting is like casting wax, buying wax (scrap or pig iron) and then waxing it into a liquid, putting it in a mold, and you get something of a different shape. (Solid-liquid-solid) forging is like making a pastry. You knead a small dough and put it in a mold to make a product of different shapes. Almost a solid At high temperatures, the shape can change to something else (solid to solid). The so-called casting, the molten metal is cast into the model to obtain the casting process. Casting focuses on the metal smelting process, as well as the casting process control process. Forging is a solid state of plastic molding, hot processing, cold processing of the points, such as extrusion, drawing, pier rough, punching and so on all belong to the forging. (2) forging is slowly forming, casting is a forming casting: molten liquid metal fills the cavity cooling. Parts of the middle easy to produce stomatal. Forging: The main method is to use extrusion molding at high temperatures. Can be refined in the grain of the workpiece.