The treatment process that carbon steel flanges need to go through after quenching:

1. Quenching and tempering treatment: The heat treatment method of high-temperature tempering after quenching is called quenching and tempering treatment. High temperature tempering refers to tempering between 500 and 650 ℃. Carbon steel flange quenching and tempering can greatly adjust the functionality and raw materials of steel, with good strength, plasticity, and resistance, and outstanding inductive mechanical functions

2. Aging treatment: In order to remove excellent measuring tools, molds, and parts that undergo changes in scale and shape during long-term use, the workpiece is often reheated to 100-150 ℃ after low-temperature tempering (low-temperature tempering temperature 150-250 ℃) before precision machining, and maintained for 5-20 hours. This treatment is called aging to ensure the stability of excellent product quality

Thirdly, it is particularly important to perform aging treatment on steel components under low temperature or dynamic load conditions to remove residual stress, stabilize the arrangement and scale of hot pressed elbows

During the heat treatment process of carbon steel flanges, due to the change in microstructure, i.e. the transformation from austenite to martensite, the increase in specific volume will be accompanied by the expansion of the workpiece volume. The phase transformation of various parts of the workpiece will occur successively, resulting in inconsistent volume growth and the generation of structural stress. The later results of organizational stress changes are tensile stress on the surface and compressive stress on the heart, which are exactly opposite to thermal stress. The magnitude of organizational stress is related to factors such as the cooling rate, shape, and chemical composition of the material in the martensitic transformation zone of the workpiece