Type 303

• Austenitic Stainless Steel
• Excellent machining characteristics
• Free machining version of Types 302 and 304 is used for parts requiring extensive machining
• Annealed condition is non-magnetic
• Slightly magnetic when cold worked
• Good corrosion resistance
• Good oxidation resistance up to 1700 degrees F

Specifications

Type 303 is covered by the following specifications:

Standard Heat Treatments

• Anneal: Heat to 1900 - 2050 F and water quench
• Harden: Type 303 cannot be hardened by heat treatment

Corrosion Resistance

• Excellent corrosion resistance
• Effectively resist attack in atmospheric exposures, sterilizing solutions, most organic and many inorganic chemicals, most dyes nitric acid and foods
• For best corrosion resistance finished parts should be free from scale and foreign particles

Forgeability

• Type 303 should be heated slowly to 2000-2150 F
• Soaked for a sufficient time, then raised to 2200 - 3250 F 
• Should not be forged below 1700 F

Machinability

• Excellent machinability

Formability

• Type 303 has limited formability because of its sulfur content

Weldability

• Only fair weldability
• Can be welded using proper procedures
• Weldability can be improved by using methods that minimize dilution of the weld metal with the melted base metal 
• Reducing the time that welds are in the hot-short temperature range and use of Type 312 (29-9) filler metal helps obtain satisfactory results