Cold forging technology is an advanced plastic forming process, which is widely used in the manufacture of various mechanical parts and structural parts. However, in the process of cold forging, forging often appears fatigue damage, affecting its service life and safety. Therefore, how to improve the fatigue life of cold forging has become an important issue in the field of manufacturing. This paper discusses the methods and measures to improve the fatigue life of cold forging from the point of view of process optimization.
Analysis of influencing factors of fatigue life of cold forging parts
Residual stress
In the process of cold forging, residual stress will be generated inside the forging, which will cause cracks and fatigue damage in the use of the forging. Therefore, reducing the residual stress is an important way to improve the fatigue life of cold forging parts.
Grain size and structure
Grain size and microstructure have important effects on mechanical properties of materials. Refining grain and improving microstructure can improve the strength and toughness of the material, thus increasing the fatigue life of cold forging parts.
Lubrication condition
Lubrication conditions during cold forging have important influence on forming quality and performance of forging. Good lubrication conditions can reduce the friction coefficient between die and blank, reduce die wear and blank deformation, and thus increase the fatigue life of cold forging forging.
Process optimization measure
Optimize heating and cooling processes
By optimizing the heating and cooling processes, residual stress levels and structure of forgings can be controlled. For example, the preheating treatment can reduce the deformation resistance and residual stress of the billet. The grain size and microstructure can be controlled by proper cooling rate, and the mechanical properties of the material can be improved.
Optimize mold design and manufacturing process
Die design and manufacturing process have important influence on forming quality and performance of cold forging. By optimizing die structure, improving die manufacturing precision and improving die lubrication conditions, the friction coefficient between die and blank can be reduced, die wear and blank deformation can be reduced, and fatigue life of cold forging can be increased.
Optimize the forming process parameters
The forming process parameters are the key factors affecting the quality and performance of cold forging parts. By optimizing the forming pressure, speed, lubrication and other parameters, the deformation behavior and residual stress level of the blank can be controlled, and the fatigue life of cold forging can be increased. In particular, numerical simulation and experimental research can be used to find the best combination of forming process parameters.
Adopt new materials and new processes
The application of new materials and new technology is an important way to improve the fatigue life of cold forging parts. For example, using high strength and high toughness titanium alloy or composite material as blank can improve the strength and toughness of cold forging forging; The use of advanced lubrication materials and lubrication technology can reduce the friction coefficient between the mold and the billet, reduce mold wear and billet deformation.
Through the in-depth analysis of the factors affecting the fatigue life of cold forging parts, this paper puts forward a series of process optimization measures, including optimization of heating and cooling process, optimization of mold design and manufacturing process, optimization of forming process parameters and the use of new materials and new processes. These measures can reduce the residual stress, refine the grain and improve the structure, reduce the friction coefficient and improve the lubrication effect, so as to increase the fatigue life of cold forging parts. However, the implementation of these measures needs to take into account factors such as production costs and production efficiency, so it needs to be continuously explored and optimized in practice. In the future, new cold forging technology and process as well as new materials and lubrication technology can be further studied to promote the continuous innovation and development of cold forging technology.
