(1) martensitic stainless steel: stainless steel structure of this kind of body centered cubic (BCC) can be the magnet, the field temperature from Oswald quench and corrosion resistance, the best, but the material is hard brittle, then to tempering can increase the ductility, but the corrosion resistance will be reduced, especially at 450 degrees Celsius to 650 degrees between the tempering, in the crystal lattice gap in the diffusion of carbon atoms to form a mesh of precipitation of chromium carbide and chromium caused by consumption near the chromium chromium component decreased, unable to form a protective film, and the loss of corrosion resistance, so the need to pay special attention to. The following is the heat treatment of various martensitic stainless steel type material temperature.
The temperature of (a) 403410416se is 650-750.
(b) the temperature of 414 is at 650-730.
(c) 431 temperature at 6. (d) 440-A, 440-B, 440-C, 420 at 680-750 C.
(2) ferritic stainless steel, the stainless steel body centered cubic structure (BCC) can be a magnet commonly used in automobile industry and chemical industry, the intensity will not change due to heat treatment, but can increase the strength of cold working method.
(3) austenite stainless steel, the stainless steel face centered cubic structure (FCC) has no effect on the magnet, such as front of these materials, easy processing, the processed material to eliminate residual stress and can be applied to different heat treatment.
(4) precipitation hardening stainless steel: the stainless steel by high temperature quenching postprocessing in low temperature, the material containing aluminum or copper, precipitation along the grain boundary sliding surface or difference rows to form compounds (inter-metalliccompounds) and can increase its strength or hardness. Commonly used precipitation hardening stainless steel 17-4PH, the other are 17-7PH, PH15-7MO, AM-350, AM-355 and so on.
(5) all kinds of stainless steel after welding heat treatment: chromium containing stainless steel, welding, in the high temperature region (heat affected zone) tends to spread precipitation and carbon synthesis of chromium carbide, caused by the local chrome component decreased, unable to form a protective film, and perforation corrosion often occurs in the area the influence of heat, can remedy the situation in the industry often after welding, the object with heat treatment, the effect can make other areas of chromium chromium diffusion is lack of area, in order to achieve the protective effect.