Wear mechanisms and its effect of CBN tool on surface roughness in machining of metallic glass

Abstract

Metallic glass is widely used owing to its excellent properties such as high strength, high hardness, and high elastic limit. Due to its challenging machining characteristics, analyzing tool wear during the machining process is of great significance for broader application. This paper presents an experimental study on the wear behavior and performance characteristics of CBN tools with a negative chamfering structure when cutting Vit1 under different cutting conditions. The analysis explored the impact of cutting parameters on the tool wear process. It shows that the cutting parameters affected the tool-wear stages. Under high cutting parameters, the tool bypasses the normal wear stage and transitions directly to the rapid wear phase. The rake face exhibits cratering and fine chipping, whereas the flank face displays normal wear bands and groove wear. The wear mechanisms of the CBN tools when cutting Vit1 include abrasive, diffusion, oxidation, and adhesive wear. These types of wear are caused by several mechanisms. The machined surface roughness is influenced not only by the increased tool wear but also by the surface quality of the wear zone on the flank face and chip adhesion.