Influence of Surface Mechanical Attrition Treatment on Fretting Wear Behaviour of Ti-6Al-4V

Abstract

Ti-6Al-4V alloy was subjected to surface mechanical attrition treatment (SMAT) by using SAE 52100 steel balls of 5 mm diameter for two treatment durations (30 and 60 min). SMAT resulted in the formation of nanostructured material on the surface and near surface regions, increased hardness, increased surface roughness and compressive residual stress on the surface. Treated samples exhibited lower tangential force coefficient (TFC) compared to untreated samples. Samples treated for 60 min exhibited higher grain refinement, higher hardness, lower surface roughness and higher TFC compared to the samples treated for 30 min. Fretting wear resistance of the samples treated for 30 min was higher than that of untreated samples and the samples treated for 60 min. Due to very high hardness and presumably reduced ductility, the fretting wear resistance of the samples treated for 60 min was lower than that of the untreated samples and samples treated for 30 min.