Alloy 321 Stainless Steel Bar - AMS 5645

Available Diameters in Inches
.4375 - 5.50
Available Diameters in Millimeters
11.113 - 139.700
  • 321 stainless bar, ams 5645 bar, ge-s400/s1000
    Alloy 321 Stainless Steel Bar - AMS 5645 - Color Code Moss Green


  • Alloy 321 stainless steel bar is a titanium stabilized austenitic chromium-nickel stainless steel which was developed to provide an 18-8 type alloy with improved intergranular-corrosion resistance. This alloy is stabilized against chromium carbide formation by the addition of titanium. Since titanium has a stronger affinity for carbon than chromium, titanium carbide precipitates within the grains instead of forming at the grain boundaries. Alloy 321 stainless steel bar should be considered for applications requiring intermittent heating between 800ºF (427ºC) and 1650ºF (899ºC), or for welding under conditions which prevent a post-weld anneal.

Nominal Composition

  • Iron - 68%
  • Chromium - 18%
  • Nickel - 11%
  • Titanium - > 5 x Carbon

Standard Inventory Specifications

  • AMS 5645
  • GE S400/S1000
  • UNS 32100
  • ASTM A193
  • ASTM A276
  • ASTM A479
  • QQ S 763
  • EN 1.4541
  • Line marked >.500 inch diameter
  • Predominantly produced by AOD process. Annealed, centerless ground or rough turned.
  • DFARS compliant

Common Trade Names

  • 321 stainless. Alloy 321, 321 

Industry Applications

  • Aerospace
  • Chemical Processing
  • Oil & Gas

Standard Inventory Lengths: 10-12 feet rl's


  • Non-magnetic. Corrosion resistance similar to Type 304 stainless steel. Alloy 321 stainless steel bar is used for welded equipment which cannot be annealed and for equipment which is operated between 800-1500˚F (427-816˚C). The elevated temperature stress rupture and creep strength of this grade is higher than Type 304 stainless steel. Room temperature yield strength is approximately 35,000 psi and tensile strength 85,000 psi.


  • The hardness of Aerodyne Alloy stock is typically 160 BHN and Alloy 321 stainless steel bar is supplied in the fully annealed condition. This grade can not be hardened by heat treatment, but small sections can be cold work hardened. For applications requiring maximum corrosion resistance, a stabilizing heat treatment at 1550-1650˚F (843-899˚C) for up to 5 hours may be used to dissolve any chromium carbides and preferentially form titanium carbides.


  • Rating: 80% of B-1112
  • Typical stock removal rate: 90 surface feet/minute with high speed tools.


  • Has a high rate of work hardening and requires a rigid set-up, plenty of power and positive cuts.

Density: 0.290 lbs/in3, 8.03 g/cm3