Due to the different uses of precision casting processing, there are many heat treatments, which can basically be divided into two categories. First, the structure will not undergo heat treatment and change or should not be changed. Second, the basic structure changes. The first heat treatment process is mainly used to eliminate internal stress caused by different cooling conditions and conditions in the stainless steel casting process. The heat treatment, precision, and mechanical properties of precision casting processing do not change significantly due to heat treatment.
For the second type of heat treatment and the main, Al Qaeda has undergone major changes, which can be roughly divided into five categories:
1. Softening annealing: Its purpose is mainly to decompose carbides, reduce their hardness and improve processing performance. It is a ductile iron with the purpose of obtaining more ferrite structure.
2. Normalizing treatment: The main purpose is to obtain pearlite and sorbite microstructure to improve the mechanical properties of stainless steel castings.
3, quenching treatment: mainly to obtain higher hardness or wear resistance, while high surface wear characteristics.
4. Surface hardening treatment: The surface hardening layer is mainly obtained, and at the same time, the surface wear resistance is extremely high.
5. Precipitation hardening treatment: Mainly to obtain high strength and elongation without causing drastic changes.
Precision casting processing and processing of heat treatment precision casting processing materials precision casting processing enterprises metal materials mainly from outsourcing materials, enterprise waste castings, pouring risers. The outsourced metal materials are often in bulk, rarely pressed into a tube, and the different materials of the material are easily confused, such as 316 materials mixed with 304 or 430 materials. Therefore, precision casting processing companies should try to purchase compressed materials. The chemical composition of each batch of purchased materials was analyzed using a spectrum analyzer. If possible, suppliers should conduct site visits to assess whether these materials are marked, protected, and isolated.
The company's waste (waste castings, pouring risers) should also be carried out in addition to rust, oil, sand cleaning, cleaning and drying, control, and p-parts. In addition, scraps of different materials should be identified, protected, separated and stored without confusion.