Abstract
Powder metallurgy (PM) SUS304 stainless steels consolidated by hot extrusion process with different oxide inclusions are investigated in terms of tensile properties and creep rupture properties at elevated temperatures. Formation of oxides at powder surfaces and within powders is dependent on the chemical composition: An addition of Al, Mn and Si generated Al, Cr-Mn and Si oxides, respectively, while Cr oxides form without additions of those elements. The ductility of PM material is reduced by Al oxides in the high temperature tensile tests above 800°C even though the material with Al oxides has a low level of oxygen content. Furthermore, Al and Si oxides in the PM materials are more detrimental to creep rupture strength at 950°C than Cr or Cr-Mn oxides.
