Effect of silicon content and aging time on density, hardness, toughness and corrosion resistance of sintered 303LSC–Si stainless steels

303LSC stainless steel powder was mixed with silicon powder; the powder mixture was then compacted and sintered at 1250 °C in bottle hydrogen. The sintered alloys were exposed to 800 °C to investigate the effect of silicon content and aging tome on density, hardness, toughness and corrosion resistance of the aged alloys. Experimental results show that the density and hardness of sintered alloys increase with increasing silicon content and aging time. σ-Phase precipitates during the aging treatment; the morphology and chemical composition of this precipitated phase vary markedly with the aging time. Variation of toughness is discussed as the consequence of two competition mechanisms σ-phase precipitation and porosity modification. Increasing silicon content and aging time decreases the corrosion resistance.