321 stainless steel

321 austenitic stainless steel is a material with excellent Stress Rupture performance and high temperature Creep Resistance Stress mechanical properties are better than stainless steel 304 material.

This grade is typically used in the 800-1500˚F temperature range where it is stabilized against chromium carbide precipitation by the addition of titanium, which results in the precipitation of titanium carbides. Type 321 has excellent intergranular corrosion resistance after exposure to this temperature range, and this grade resists oxidation up to 1500˚F and has higher creep and stress rupture properties than 304/304L. It also possesses good low temperature toughness and is non-magnetic in the annealed condition.

Chemical Composition(wt%) limits as specified in ASTM A240 and ASME SA240*.

Element	321
Carbon	0.08
Chromium	17.0-19.0
Nickel	9.0-12.0
Manganese	2.00
Silicon	0.75
Nitrogen	0.10
Phosphorus	0.045
Sulfur	0.030
Titanium	5(C+N) min / 0.70 max

* Maximum, unless range is indicated

Mechanical Properties requirements for annealed product as specified in ASTM A240 and ASME SA240.

Property	321
Yield Strength, min. (ksi)	30
Tensile Strength, min. (ksi)	75
Elongation, min. (%)	40
Hardness, max. (Rb)	95

Used in open field machines, heat resistant parts of building materials and parts with difficulty in heat treatment, which require high chemical, coal and petroleum industries to resist grain boundary corrosion.
1. Oil exhaust combustion pipeline
2. Engine exhaust pipe
3. Boiler shell, heat exchanger, heating furnace components
4. Mute parts for diesel engine
5.Boiler and pressure vessel
6. Chemical tanker
7.Expansion joints
8. Spiral welded pipe for furnace pipe and dryer