303 Stainless Steel Bar

UNS S30300 (Grade 303)

303 stainless steel bar, also known as UNS S30300 and Grade 303, is considered a free machining stainless steel. 303 stainless steel’s corrosion resistance and great machinability make it one of the most popular free machining stainless steels available. It is used in a wide variety of parts from screw to general machining. Grade 303 does not respond to heat treatment, but the toughness is still excellent as with other austenitic grades.

Industries that use 303 include:

  • General machining
  • Screw machining

Products partially or completely constructed of 303 include:

  • Aircraft fittings
  • Bushings
  • Gears
  • Nuts and Bolts
  • Screws
  • Bushings
Stocking Diameters ½” to 13”
Material Lengths Up to 12’
Bar Specifications
Uns Type Ams Astm Federal Characteristics
S30300 303 5640 A-314


Atmospheric corrosion resistance with improved mechanical properties. 303 is a 300 Grade with increased sulfur for good machinability.
Chemistry Analysis
.15 2. .2 15 Min. 1. 17. – 19. 8. – 10. .6 .5   NM

The information above is not warranted, guaranteed, or for design purposes.

The information above is not warranted, guaranteed, or for design purposes.

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