Tribological characteristics of additively manufactured Ti6Al4VxCryNi alloys

Abstract

This paper presents comparative study of tribological characteristics of μ-plasma arc additively manufactured Ti6Al4V5Cr, Ti6Al4V2.5Cr2.5Ni, Ti6Al4V5Ni alloys with Ti6Al4V alloy. Addition of Cr and/or Ni to Ti6Al4V alloy is found to refine the grains of α-Ti phase and formed harder intermetallic Cr2Ti and Ti2Ni phases in the developed alloys. It increased their hardness, decreased friction coefficient, wear volume and wear rate, worn scar depth, surface roughness, and thickness of plastically deformed layer. Wear volume and wear rate increased with the applied load for all the four alloys. It is due to increase in contact area with the silicon nitride ball which led to more plastic deformation and subsequently removal of more material from the alloys. Their worn surfaces exhibited shallow grooves along the sliding direction, compacted debris, delamination whereas Ti6Al4V showed deep grooves along the sliding direction and micro-cracks. Ti6Al4V5Cr alloy demonstrated the highest wear resistance followed by Ti6Al4V2.5Cr2.5Ni, Ti6Al4V5Ni, and Ti6Al4V alloys. The developed wear resistant Ti6Al4V5Cr, Ti6Al4V2.5Cr2.5Ni, and Ti6Al4V5Ni alloys will be very useful in avionics, space, automobile, and manufacturing of dies and moulds. © 2024 Elsevier Ltd