UNS: S32100
EN-DIN: 1.4541
Printable PDF: 321 Stainless Steel Alloy Data Sheet
Industries supplied include: annealing covers, high-temperature tempering equipment, diesel and heavy duty automotive exhaust systems, firewalls, stack liners, heat shields, boiler casings, welded pressure vessels, jet aircraft components, bellows, and oil refinery equipment. 321 grade stainless has excellent resistance to oxidation and corrosion and possesses good creep strength. Type 321 is a stabilized austenitic stainless steel similar to type 304 but with titanium addition used in applications involving continuous or intermittent service at 800-1500 oF (427-816 oC).
Nominal Composition
| C: | 0.080 max |
| Mn: | 2.0 max |
| P: | 0.045 max |
| S: | 0.030 max |
| Si: | 0.75 max |
| Cr: | 17.0 – 19.0 |
| Ni: | 9.0 – 12.0 |
| Ti: | 5X(C+N) – 0.70 |
| N: | 0.10 max |
| Fe: | BAL |
Physical Properties
At 70°F (At 20°C)
Density
0.29 lb./in³ / (8.09 g/cm³)
Modulus of Elasticity (E)
28.0 x 10³ ksi in tension / (193 x 10³MPa in tension)
Coefficient of Expansion
9.2 x 10-6 microinches/in.-°F (32-212°F) / (16.6 μm/m-°C) (0-100°C)
Electrical Resistivity
28.4 μ ohm.in / (72 μ ohm.cm)
Thermal Conductivity
9.3 Btu-in./ft.²hr.-°F (100°C)/ (16.0 W/m-K) (100°C)
Applicable Specifications
AMS 5510, ASTM A240
Typical Mechanical Properties – Typical Room Temperature Mechanical Properties
Typical mechanical properties are based on AK source, ASTM A240
Condition
Annealed
Tensile Strength (UTS)
85 ksi (586 MPa)
0.2% YS
35 ksi (241 MPa)
Elongation% in 2” (50.8 mm)
55%
Hardness Rockwell
70 HRBW
**The information and data in this product data sheet are accurate to the best of our knowledge and belief, but are intended for general information only. Applications suggested for the materials are described only to help readers make their own evaluations and decisions, and are neither guarantees nor to be construed as express or implied warranties of suitability for these or other applications. Data was obtained from our melt sources with data referring to mechanical properties and chemical analyses are the result of tests performed on specimens obtained from specific locations with prescribed sampling procedures; any warranty thereof is limited to the values obtained at such locations and by such procedures. There is no warranty with respect to values of the materials at other locations. Further information should be sought from the melt sources.
Additional Information on 321 Stainless Steel Alloy
‘Stainless’ is a word coined with reference to the creation of these steels for use as cutlery. Stainless was adopted as a generic term for such steels. Currently, it covers a broad array of steel grades and types for oxidation or corrosion resistant purposes.
Stainless steels include iron alloys that have a minimum of 10.5 percent chromium. Additional alloying components become added to enhance their properties and structure like cryogenic toughness, strength, and formability.
Stainless steels include metals like:
- Copper
- Titanium
- Molybdenum
- Nickel
Also, non-metal additions are made, with the primary ones being:
- Nitrogen
- Carbon
The primary stainless-steel requirement is that it must be resistant to corrosion for a specified environment or application. The choice of a certain stainless steel “grade” or “type” must first meet the requirements of corrosion resistance. Other physical or mechanical properties might have to be taken into consideration to accomplish the overall requirements for service performance.
Type 321 stainless steel is like type 304 stainless steel; however, it features a Titanium addition of about 5 times the carbon level. This addition of Titanium is made to eliminate or reduce chromium carbide precipitation, which results from exposure to high temperatures or welding. Its resistance to intergranular corrosion is one of the key features of 321 stainless steel.
Maximum stabilization is achieved by annealing from 1750° to 1850° F. Stainless steel 321 sees extended use in aircraft parts, like exhaust systems in which running temperatures are greater than 800-degree Fahrenheit. It is also used where corrosive conditions aren’t that severe, benefiting from its resistance to scaling and vibration fatigue.
Common applications of 321 stainless steel include jet engine parts, welded equipment, high temperature chemical processing equipment, and aircraft exhaust stacks & manifolds. Stainless steel 321 is also commonly used in applications such as expansion joints, thermal oxidizers, and refinery equipment.
When comparing stainless steel 321 to other alloys such as 304 and 304L, you will see that 321 steel offers higher creep and stress rupture properties. When exposed to low temperatures, 321 stainless steel exhibits good toughness. As mentioned, 321 stainless steel has good corrosion resistance which is very comparable to alloy 304 and is used with most diluted organic acids and chloride- and fluoride-free caustic solutions at moderate temperatures. Additionally, 321 stainless steel is weldable and is processed within standard fabrication practices.
ESM Hampshire Mill cold-rolled and hot-rolled steel come in an array of shapes perfect for your needs, including plates, sheets, tubes, and bars. We are able to cut metal to your precise specifications.
For more information about 321 stainless steel, fill out our contact form here, or speak to an ESM Hampshire Mill representatives at 847-683-0500.
