The heat treatment of steel castings is one of the indispensable production processes to control the microstructure of steel castings and make them have the required properties. Changshu Hongqiao Casting steel Co., LTD. Customized steel casting Marine steel casting ABS Marine engineering service BOP casting steel cast
First, the main process elements of steel casting heat treatment
The heat treatment of steel castings consists of three stages: heating, holding and cooling. The determination of its process parameters is based on ensuring product quality and energy saving.
1. Heating Heating is the most energy consuming process in the heat treatment process. The main technical elements in the heating process are the selection of appropriate heating mode, heating rate and charging mode.
2. The austenitic insulation temperature of steel casting should be selected according to the chemical composition of the cast steel and the required performance. Two aspects should be considered to determine the holding time of steel casting heat treatment: the singularity is that the temperature of the casting surface and the core are consistent; The second is the homogenization of the organization, so the insulation residence time depends on the thermal conductivity of the cast steel, and the wall thickness of the broken face of the casting is usually the main basis for estimating the insulation time.
3. The cooling cast steel can be cooled at different rates to complete the phase transformation of the steel after insulation, in order to obtain the required metallographic structure and achieve the specified performance indicators. In general, increasing the cooling rate is conducive to obtaining a good state of organization and refining the salute, thereby improving the performance of the steel, but it is easy to produce large stresses on the casting, resulting in deformation or cracking of the complex structure of the casting. The heat treatment cooling media of steel castings are commonly used air, oil, water, salt water and molten salt.
Second, the heat treatment of cast steel parts
According to different heating and cooling conditions, the main heat treatment methods of cast steel are: annealing, normalizing, homogenizing treatment, quenching, tempering and so on.
Changshu Hongqiao Cast Steel Co., Ltd. mainly produces various specifications of carbon steel, high, middle and low alloy steel, stainless steel, heat-resistant steel, high manganese steel, high chromium cast iron. For petroleum, chemical industry, metallurgy, mining machinery, coal mining machinery, wind power, nuclear power, Marine and other industries to provide high-quality steel casting, and export abroad. Changshu Hongqiao Casting steel Co., LTD. Customized steel casting Marine steel casting ABS Marine engineering service BOP casting steel cast