Impact-abrasive-corrosion wear of Fe-based alloys: Influence of microstructure and chemical composition upon wear resistance

A wide range of heat treated iron-based alloys (steels and white cast irons) was subjected to wear test in laboratory mill with the aim of discovering the correlation between microstructure type and impact-abrasive wear resistance under corrosion. The role of microstructure and chemical composition was identified through analysis of wear behavior under a range of slurries (pH 1-14) and analysis of the worn surface. It was found that the best wear performance is achieved with martensitic structure in steels containing not less than 13 wt% Cr. The results showed that austenitic Cr3Ni, Cr3Mn and Mn-based steels do not demonstrate significant advantages in wear resistance over low-alloyed steels having martensitic microstructure. It was found that high-chromium white cast irons have average wear resistance because of embrittlement due to the presence of coarse eutectic carbides in the structure. It was also noted that wear resistance depends both on corrosive resistance and deformation resistance. Deformation resistance seems to play a more important role because it can largely compensate for the lack of corrosion resistance. It was concluded that low-alloyed hypereutectoid steel having “martensite-austenite-carbides free” microstructure could be considered the most effective alloy for use in wear application, taking into account its low cost.