CORROSION-RESISTANCE OF SINTERED STAINLESS-STEEL CONTAINING NICKEL-BASED ADDITIVES

The effect of nickel based brazing powder additions on the corrosion b ehaviour of sintered austenitic stainless steel in 0.5M H2SO4 has been investigated. It has been found that the corrosion resistance of the sintered mixture increased substantially and proportionally to the bra zing powder content in the range 1-5 wt-%. The improvement in the corr osion resistance originates from the reduction in the open interconnec ted porosity due to the formation of a transient liquid phase. A corro sion resistance similar to wrought austenitic stainless steel was obse rved in the presence of 5 wt-% of fine particle additive. The presence of coarse particle additive has only a local effect and does not subs tantially affect the environmental behaviour of the sintered samples.