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Stainless Steel - 321

Stainless Steel 321

Corrosion Resistant Stainless 321 – AMS5510, AMS5645, AMS5557, AMS5559, AMS5570, AMS5576, Mil-T-8606, Mil-T-8808, QQ-S-766, UNS S32100, UNS S32109

Product description

Type 321 is a stabilized stainless steel which offers as its main advantage an excellent resistance to intergranular corrosion following exposure to temperatures in the chromium carbide precipitation range from 800 to 1500° F (427 to 816° C). Type 321 is stabilized against chromium carbide formation by the addition of titanium.

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Austenitic stainless steels are considered to be the most weldable of the high-alloy steels and can be welded by all fusion and resistance welding processes.

Used where freedom from intergranular corrosion is desired and milder corrosive conditions exist. It is used in parts subjected to sustained heating in or slow cooling through the range of 800º to 1500ºF. It is well suited for cold-drawing and forming operations. In aircraft, it is used particularly for such applications as exhaust stacks, manifolds, and ring collectors.

Type 321 is resistant to intergranular corrosion. Its general corrosion resistance is somewhat less than that of type 304. It tends to form a light rust film in corrosive atmospheres, but this rusting is not progressive.

Technical Specification

SpecificationMaterialPublication Date
AMS5510Steel, Corrosion and Heat-Resistant, Sheet, Strip and Plate 18Cr - 10.5Ni - 0.40Ti (SAE 30321) Solution Heat Treated01/11/1941
AMS5645Steel, Corrosion and Heat Resistant, Bars, Wire, Forgings, Tubing, and Rings 18Cr - 10Ni - 0.40Ti (321) Solution Heat Treated01/11/1941
AMS5557Steel, Corrosion and Heat-Resistant, Seamless or Welded Hydraulic Tubing 18.5Cr - 10.5Ni - 0.40Ti (SAE 30321) Solution Heat Treated01/08/1955
AMS5559Steel, Corrosion and Heat-Resistant, Welded Tubing 18Cr - 10.5Ni - 0.40Ti (SAE 30321) Thin Wall Solution Heat Treated01/01/1958
AMS5570Steel, Corrosion and Heat-Resistant, Seamless Tubing 18Cr - 11Ni - 0.40Ti (321) Solution Heat Treated04/12/1939
AMS5576Steel, Corrosion and Heat-Resistant, Welded Tubing 18Cr – 10.5Ni – 0.40Ti (321) Solution Heat Treated15/06/1952

300 series austenitic stainless steels are non-magnetic. When nickel is added to stainless steel in sufficient amounts, the crystal structure changes to “austenite.” The basic composition of 300 series austenitic stainless steels is 18% chromium and 8% nickel. This enhances their corrosion resistance and modifies the structure from ferritic to austenitic. Austenitic grades are the most commonly used stainless steels, accounting for more than 70% of production.

Technical Data

How strong is it? What's it made of?
SpecificationTensile StrengthYield StrengthElongation
AMS551070-100 KSI25 KSI Min40%
AMS555775-105 KSI30 KSI Min30%
AMS5570105 KSI Max30 KSI Min30%
ElementLower %Upper %
Carbon-0.080
Manganese-2.000
Silicon0.2501.000
Phosphorus-0.040
Sulfur-0.030
Chromium17.00019.000
Molybdenum-0.750
Columbium (Niobium)--
Titanium5x(C+N)0.700
Nitrogen-0.100
Cobalt--
Copper0.0000.750
Nickel9.00012.000

Aerocom Stock List

Sheet & Plate Bar
Sheet Size (Inches)
Thickness (Inches)60" x 36"
0.016X
0.025X
0.032X
0.040X
0.050X
0.063X
0.080X
0.100X
0.125X
0.250X
0.500X
0.750X
1.000X
1.500X
Stock
InchesDiameter
0.125X
0.250X
0.375X
0.438X
0.500X
0.625X
0.750X
0.875X
1.000X
1.125X
1.250X
1.500X
1.750X
2.000X
2.500X

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