The wear behaviour of machine tool guideways clad with WNi, WCo and WCu using gas tungsten arc welding

Abstract

This work examines the feasibility of applying wear resistant cladding material to grey cast iron, which was usually used as the material of machine tool structures, to improve their wear performance. The extent to which cladding powders and post-treatment that affects the wear resistance of the clad layer is also studied. Additionally, the bonding strength between the clad layer and the matrix with different compositions was also evaluated. Wear testing was conducted using a rotating tribometer with a pin-on-disk configuration. According to those results, a WNi clad layer formed with W (90 wt.%) and Ni (10 wt.%) powder, outperforms clad layers formed by similar powders with different cladding materials, in terms of wear performance. Although the other clad layers, such as WCu, WCo and W clad layer, had different shapes of precipitate, their wear performance was also better than the base metal, obviously. Furthermore, the effect of various angles between the cladding and sliding direction, and normalizing treatment on the wear performance of the clad layer is also evaluated. Experimental results indicate that wear performance depended on cladding orientation and normalizing treatment. The normalizing process not only increased the bonding strength between the clad layer and the matrix, but also improved the wear performance of the clad layer under all cladding conditions.