On the wear mechanism of iron and nickel based transition metal-metalloid metallic glasses

Abstract

The tribological behaviour of two iron based and one nickel based metal-metalloid glasses has been studied during dry sliding wear in order to understand the basic mechanism of the wear process. Detailed transmission and scanning electron microscopic characterisation of the wear surfaces and the debris together with the analysis of frictional data strongly suggest a primary role of the transfer layer in the wear process of iron based glasses. The observed results can be rationalised by considering the operation of a dynamic recrystallisation process of the debris at the high strain rates typically encountered during the present investigation and is strongly supported by the TEM observation of an ultrafine grain structure of the debris. On the other hand, the separation of crystallised particles plays an important role in the wear process of those glasses which crystallise under dry sliding conditions. Our observation on nickel-based glass confirms such a behaviour.