The Production Process Of Austenitic Stainless Steel

The production process of austenitic stainless steel has good performance, especially chromium nickel austenitic stainless steel. By using conventional methods to produce special steel, various commonly used specifications of plates, pipes, strips, wires, bars, forgings, and castings can be smoothly produced. Due to the high content of alloying elements (especially chromium) and low carbon content, arc furnace with argon oxygen decarburization (AOD) or vacuum deoxidation decarburization (VOD) methods are often used to produce such stainless steel materials in large quantities. For high-end grade small batch products, vacuum or non vacuum non induction furnace smelting can be used, and if necessary, electroslag remelting can be added.
The excellent thermoplastic properties of chromium nickel austenitic stainless steel make it easy to perform hot processing such as forging, rolling, hot piercing, and extrusion. The heating temperature of the steel ingot is 1150-1260 ℃, and the deformation temperature range is generally 900-1150 ℃. Steel grades containing copper, nitrogen, and stabilized with titanium and niobium tend to rely on low temperatures, while high chromium and molybdenum steel grades tend to rely on high temperatures. Due to poor thermal conductivity, the insulation time should be longer. After hot processing, the workpiece can be air-cooled. Chromium manganese austenitic stainless steel has a strong sensitivity to hot cracking. When the steel ingot is opened, small deformation and multiple passes are required, and forgings should be stacked and cooled. It can perform cold processing techniques such as cold rolling, cold drawing, and spinning, as well as forming operations such as stamping, bending, curling, and folding. The work hardening tendency of chromium nickel austenitic stainless steel is weaker than that of chromium manganese steel, and the cold deformation after one annealing can reach 70% to 90%. However, due to the high deformation resistance and strong work hardening tendency of chromium manganese austenitic stainless steel, the number of intermediate softening annealing should be increased. The general intermediate softening annealing treatment is water cooling at 1050-1100 ℃.
Austenitic stainless steel can also be used to produce castings. In order to improve the fluidity of molten steel and improve casting performance, the alloy composition of cast steel should be adjusted accordingly: increasing silicon content, relaxing the range of chromium and nickel content, and increasing the upper limit of impurity element sulfur content.