Friction and wear behavior of Cu–Cr–Zr alloy lubricated with acid rain

Abstract

Purpose – The purpose of this paper is to investigate the tribological properties of a Cu–Cr–Zr alloy lubricated with acid rain. Design/methodology/approach – The Cu 2.5 weight per cent–Cr-0.08 weight per cent–Zr alloy was produced in a vacuum induction furnace. The H2SO4 + H2O, HNO3 + H2O and H2SO4 + HNO3 + H2O mixtures with pH of 5 were used as acid rain. Pure water was used as rain. The friction and wear properties of Cu–Cr–Zr alloy/American Iron and Steel Institute (AISI) 52100 steel couples lubricated with acid rain were investigated using a reciprocating ball-on-disc friction and wear tester (Optimol SRV, Germany). For investigating the properties of the alloy and wear scars, scanning electron microscopy, X-ray diffraction microscopy, energy dispersive X-ray spectrum, transmission electron microscopy and X-ray photoelectron spectroscope were used. Findings – The wear rate of the Cu–Cr–Zr alloy lubricated with H2O containing HNO3 (pH = 5) was larger than pure water under the same conditions. The tribofilms containing Cu, Cr, Zr, S and N formed during sliding with acid rain, but corrosion also took place at that time. Originality/value – The wear rate of the Cu–Cr–Zr alloy lubricated with H2O containing HNO3 (pH = 5) was larger than pure water, the wear and corrosion took place during sliding. As the trolley wires, the life of the Cu–Cr–Zr alloy was influenced by the environment.