The heat treatment process of copper forgings in construction machinery usually includes annealing, aging and hardening. The following is a common heat treatment process and its effect evaluation:
- Annealing: the copper forgings are heated to the appropriate temperature (usually 650℃-700℃), kept for a period of time and then slowly cooled. The purpose of annealing is to eliminate the stress in the forging process and improve the plasticity and toughness of copper forgings. The annealed copper forging has bright surface and uniform internal structure.
- Aging: The annealed copper forgings are reheated to a lower temperature (usually 300℃-500℃), held for a period of time, and then air cooling. Aging treatment can improve the strength and hardness of copper forgings, improve fatigue resistance and stability of size.
- Hardening: Through cold deformation or rapid cooling after heating, the structure of copper forgings changes phase to improve hardness and strength. After hardening, the surface of the copper forgings may show a lighter color and the internal structure is dense.
The effect evaluation mainly includes the following aspects:
- Mechanical properties of copper forgings: The influence of heat treatment processes such as annealing, aging and hardening on mechanical properties such as strength, hardness and plasticity of copper forgings is evaluated by means of tensile test and hardness test.
- Microstructure observation: Metallographic microscope and other equipment are used to observe the microstructure changes of copper forgings after heat treatment and evaluate the effect of heat treatment process. Factors such as grain size, morphology and distribution of precipitated phase should be paid attention to.
- Dynamic performance evaluation: Through fatigue test, impact test and other methods to evaluate the dynamic performance of copper forgings in actual use, to judge the influence of heat treatment process on copper forgings.
It should be noted that the specific heat treatment process and effect evaluation should be determined according to the specific copper alloy material and forging shape to ensure the best mechanical properties and service life. It is recommended to consult a professional heat treatment engineer or materials engineer for more detailed and accurate advice before performing heat treatment.