Wear Regime and Wear Mechanism Map for Spark-Plasma-Sintered Cu-15Ni-8Sn-0.2Nb Alloy under Oil Lubrication

Abstract

Mild and severe wear behaviors of a spark plasma-sintered Cu-15Ni-8Sn-0.2Nb alloy were studied as a function of applied load and sliding velocity. Experiments were performed under oil-lubricated conditions using a block-on-ring (GCr15 bearing steel) configuration within a load range of 50-700 N and a sliding velocity of 0.05-2.58 m/s. Lubrication regime map was constructed according to the as-developed Stribeck curve. The oil-lubricated sliding wear of Cu-15Ni-8Sn-0.2Nb alloy was classified into two dominated modes of wear: mild wear and severe wear. Nonlinear fitting method was used to determine the transition boundary between mild and severe wear. The form of main transition between mild and severe wear was identified as load-induced transition. The dominated wear mechanisms in each wear regime were identified and classified in a wear mechanism map. Chemical reaction between oil and friction pairs occurred in very severe wear regime, potentially accelerating delamination wear.