Multilayer alloys are attractive for their desirable electrical and mechanical properties [1,2]. Recent studies have also shown that multilayer alloys possess increased wear resistance. Ruff et al. [3-5] studied sliding wear behaviour of nickel and copper multilayer alloys with layer spacings of 3.8-100 nm and found that nickel and copper multilayer alloys offered substantially increased resistance to unlubri-cated sliding wear against steel when compared with copper or nickel. The improvements in wear resistance were attributed to (1) barriers to dislocation slide through the interface between adjacent layers, and (2) increase in flow stress due to the small dimension of the individual (nickel, copper) layers. Although the studies mentioned above provided some insights into the understanding of wear behaviour of multilayer materials, it is not sufficient to fully explain the wear mechanisms. In previous studies, researchers adopted traditional methods, such as a sliding test, and the wear processes were relatively complicated: during wear, the surface asperities of the slider slid across the tested surface and produced many microscratches in the same wear track repeatedly, where any scratch produced earlier, would be covered or mixed by others From the worn surface, it was almost impossible to determine what happened in a single sliding event and how a layer behaved, from deformation to removal, when cut or ploughed by an abrasive, which is, however, very important in the study of the wear mechanisms of a multilayer alloy. In the present study, the abrasive behaviour of nickel and copper multilayer alloys has been investigated by using a single pendulum scratch tester to simulate a single event of an abrasive element scratching a surface. The aim was to reveal the anti-wear mechanisms of multilayer alloys further by observing the abrasive behaviour of the layers from deformation to removal.
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