How to test the quality of forging in Haokun factory?
In the heat treatment of forgings, the heat treatment stress is an important consideration in the formulation process. Some stresses are generated in the heating and cooling process and disappear with the end of these processes, which is the instantaneous stress; some stresses are the balance stress that still exists within the forging after the heat treatment, which is the residual stress. During heat treatment, if the resulting instantaneous stress force reaches the yield point of the material at this temperature, the forging will produce plastic deformation and relax the stress. If the instantaneous stress is greater than the breaking strength of the material, it is possible to crack the forging until the fracture. Even if the instantaneous stress is less than the strength limit of the material, there are always some metallurgical defects inside the large forgings, which cause great stress concentration at these defects, to further expand the original defects, and even cause the fracture of the forgings. Therefore, controlling the size of the instantaneous stress is an important problem in formulating the heat treatment process of large forgings. The influence of heat treatment residual stress on the workpiece is dual, with good influence and bad influence. If the residual stress is the same as the part, it can reduce the strength of the part, and if on the contrary, it will improve the strength of the part. For some important large forgings, the presence of participation stress should be less than 10% of the material yield point. In order to ensure the quality of the forgings and improve the service performance and service life of the products, in addition to checking the quality of the forgings at any time in the production process, the forgings must also be inspected by full-time personnel before warehousing. The contents of forging inspection include: forging geometry and size, surface quality, internal quality, mechanical properties and chemical composition and other aspects, and each aspect contains several contents.
