321/301 stainless steel

321 stainless steel is a titanium stabilized austenitic stainless steel with good corrosion resistance. Usually non-magnetic, but may display magnetism during heating. It has excellent resistance to chromium carbide precipitation when exposed to high temperatures.

It also has higher creep and stress rupture properties than 304 stainless steel. All these properties are maintained at high temperatures, making 321 particularly suitable for high temperature applications. 321H grade is an improved version of 321 grade. It has enhanced creep resistance and its higher carbon content improves its strength at higher temperatures.

Types 321 and 347 stainless steel are used in aircraft and aerospace components, expansion joints, bellows, furnace components, heat exchangers, heating element piping and chemical process equipment, among others.

301 stainless steel

301 stainless steel has the same corrosion resistance as 304 in mildly corrosive environments at room temperature. However, due to the low chromium content of 301 (16-18%), its corrosion resistance is low in extremely corrosive and high-temperature environments. 301 stainless steel has high strength and can be used in annealed and cold working conditions. It is suitable for welding, however, welded 301 parts require annealing to dissolve chromium carbide precipitation caused by welding and prevent intergranular corrosion.

301L is a variation of 301 with improved ductility and weldability, it does not require annealing for maximum corrosion resistance. Another variant is 301LN, which contains higher nitrogen and has a higher work hardening rate, neither of which requires annealing.

301 and 301LN stainless steel are used in aircraft parts, rail cars, cars, trucks, trailers, appliances, curtain wall structures, etc.

301L stainless steel is used for pressure vessels, doors and drainage parts, vessels, etc.