Heat treatment technology of lost foam casting

In the process of heating and cooling, there will be group increase transformation of steel, which is the fundamental reason why the properties of steel can be improved by heat treatment. Through heat treatment, the potential of materials can be brought into full play and the properties of steel can be improved.

During the heat treatment of steel damping support, due to the uneven wall thickness, the heating rate and cooling rate of each part are inconsistent, which will lead to the inconsistent increase of casting groups at different sampling positions, and then affect the test results of mechanical properties. Therefore, in this test, samples are taken from the casting body, and the sampling scheme is consistent with the sampling scheme for the study of carburizing defects. The sample size is 40mm × 40mm × 200mm, and then the energy-saving box furnace is used for heat treatment to ensure the consistency of various parameters.

ZGS10CrNiCu is a hypoeutectoid steel with total alloying element content of lt; 4%, and normalizing is adopted in heat treatment process. The samples were evenly laid during charging, the heating rate was not higher than 200 ℃ / h, the holding temperature was 930 ± 10 ℃, the holding time was 3 h, and the samples were naturally air cooled after being discharged from the furnace. After the sample is cooled to room temperature, it is processed into standard sample for mechanical property test.