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Thin films of polyacrylonitrile (PAN) grafted on nickel have been studied as a substitute for gold coatings of low-level semi-permanent electric contacts. Various heat treatments were performed to diminish the electrical resistivity of the layer. In this paper we describe the tribological properties of the treated films submitted to reciprocal wear tests. These tests are performed with ball/plane contacts with the PAN film deposited on the plane. XPS analysis of the heat-treated layers shows the evolution of the composition with both temperature and duration of the treatment. Auger analysis is then used as a tool to analyse the failure mode of the layer. The results show that a first stage of wear can be described as a slow decrease of the PAN thickness. Metal/metal junctions are then initiated and lead to the onset of failure. Heat treatment is shown to improve the mechanical behaviour of the layer up to a limiting value imposed by the brass substrate.