Abstract
Powder metallurgy SUS304 stainless steels consolidated by hot extrusion process with different oxygen contents from about 100 to 250 ppm were investigated in terms of mechanical properties at elevated temperatures. Dispersion of oxide inclusions consisting of Cr-Mn-Al was observed while granular alumina was found in the conventional material. For the slow strain rate testing, tensile strength of powder metallurgy SUS304 was higher than the conventionally produced counterpart at temperatures up to 800°C, irrespective of oxygen content. The value of reduction of area decreases with increasing oxygen content in the powder metallurgy material tested at temperatures from 650 to 950 °C. For the high strain rate testing from 850 to 1400°C, the powder metallurgy materials showed higher strength and ductility than the conventional material in the entire range, independent of oxygen content.
