Stainless steels are widely used for their oxidation resistance at elevated
 temperatures. In air, a protective scale is formed which is generally quite
 stable up to about 1500F to 1600F unless substantial cycling of temperature
 occurs.

     Typical applications and maximum service temperatures follow:

         Alloy      Temperature   Application
          409         1500F      Automotive mufflers
          446         2100F      Industrial furnace components
          304         1600F      Alloy of reference
          309         1800F      Industrial and refinery furnaces
          310         1900F      Industrial and process furnaces bolting
          321/347     1600F      Automotive gaskets


             Special Considerations for High Temperature Service

 Water vapor and SO2, if present, can accelerate oxidation rates of stainless
  steels.  H2S and sulfur vapors are more aggressive to stainless steels than
  oxygen and substantially reduce the maximum allowable temperature in air.

 Brittle failures under load have occasionally occurred from 885F
  embrittlement in the ferritic grades and from sigma formation in the
  1000-1500F range in 309 and 310.
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