Stainless Steel 321 Sheet/Plates
Great Steel & Metals offer superior quality of stainless steel 321 sheet/ plates to all its valuable customers. In the stainless steel, the alloy 321 grade is a stabilized stainless steel plate and it offers main advantage with as excellent resistance to the intergranular corrosion and subsequent exposure to the chromium carbide precipitation temperatures ranging from 800 to 1500°F. By the addition of titanium, alloy 321 stainless steel plate is against the formation of chromium carbide.
On account of its good mechanical properties, alloy 321 stainless steel plate is also advantageous for service at high temperature. As compared to alloy 304 and particularly alloy 304L that could also be considered for the exposures where the concerns are intergranular corrosion and sensitization, higher stress rupture and creep properties are provided by alloy stainless steels.
The alloy grade 321 has goo general resistance top corrosion and is a stainless steel plate that is titanium stabilized. After getting exposed to the temperatures in the range of 800- 1500°F in the chromium precipitation, it offers excellent resistance to the intergranular corrosion. Oxidation to 1500°F is resisted by the alloy and it has higher stress and creep rupture properties as compared to the 304 and 304L alloys. Also, good low temperature toughness is possessed by this.
Higher carbon (0.04-0.10) version of the alloy is alloy 321H (UNS S 32109) stainless steel plate. For enhanced creep resistance and to provide elevated strength at temperature above 1000°F, the stainless steel 321 alloy is developed. In most cases, dual certification is enabled by the carbon content of the plate.
By heat treatment, alloy 321 stainless steel plate could not be hardened and it could be done with only cold working. By using the standard shop fabrication practices, this can be processed and welded easily.
- Aerospace – piston engine manifolds
- Chemical Processing
- Expansion Joints
- Food Processing – equipment and storage
- Petroleum Refining – polythionic acid service
- Waste Treatment – thermal oxidizers
- Pharmaceutical Production
Alloy 321 stainless steel plate exhibits good general corrosion resistance that is comparable to 304. It was developed for use in the chromium carbide precipitation range of 1800 – 1500°F (427 – 816°C) where un-stabilized alloys such as 304 are subject to intergranular attack.
The alloy can be used in most diluted organic acids at moderate temperatures and in pure phosphoric acid at lower temperatures and up to 10% diluted solutions at elevated temperatures. Alloy 321 resists polythionic acid stress corrosion cracking in hydrocarbon service. It can also be utilized in chloride or fluoride free caustic solutions at moderate temperatures.
Alloy 321 stainless steel plate does not perform well in chloride solutions, even in small concentrations, or in sulfuric acid service.
Weight % (all values are maximum unless a range is otherwise indicated)
0.12 BTU/lb-°F (32 – 212°F)
444 J/kg-°K (0 – 100°C)
Modulus of Elasticity
28.0 x 106 psi
Thermal Conductivity 212°F (100°C)
2550 – 2635°F
1398 – 1446°C
72 Microhm-cm at 20°F
Mean Coefficient of Thermal Expansion
Typical Values at 68°F (20°C)
Alloy 321 stainless steel plate can be easily welded and processed by standard shop fabrication practices.
The high sulfur content of Alloy 303 also has a detrimental impact on hot workability. If hot forming is required, once again, 304 should be considered as an alternate selection.
The alloy is quite ductile and forms easily.
The cold work hardening rate of 321 stainless steel plate makes it less machinable than 410 stainless steel, but similar to 304. The table below provides relevant machining data.
Alloy 321 stainless steel plate can be readily welded by most standard processes. A post weld heat treatment is not necessary.