Experimental study on wire-electrical discharge machining of zirconium-based metallic glass

Abstract

In this paper, the new alloy material, zirconium-based bulk metallic glass (Zr41.2Ti13.8Cu12.5Ni10Be22.5), which is hard and brittle, was the research object. Since the process of wire-electrical discharge machining offers the advantage of processing hard and brittle conductive materials, the effects of discharge parameters on material removal rate, surface roughness, surface morphology, carbonization and crystallization have been studied by changing discharge voltage, peak current and pulse width. The results showed that material removal rate and surface roughness increased with the increase of peak current and pulse width. Compared to peak current and pulse width, voltage exerted a less influence on material removal rate and surface roughness. The surface of the workpiece after processing presented fish-scale structure with some bumps, microspheres and droplets. As the discharge energy increased, more carbon deposits from cutting fluid were deposited on the surface of the workpiece, resulting in an increase of the carbon content which accelerated surface carbonization. The workpiece processed by low discharge energy kept a good amorphous state, but its surface layer had a tendency to crystallize. Furthermore, with the increase of discharge energy, sharp diffraction peaks began to appear, and crystallization occurred. Based on the current inadequacy of research on wire-electrical discharge machining of zirconium-based metallic glass, the purpose of this study is to provide a reference for further research on wire-electrical discharge machining of zirconium-based metallic glass.