An experimental investigation of wire electrical discharge machining of hot-pressed boron carbide

Abstract

The present work discusses the experimental study on wire-cut electric discharge machining of hot-pressed boron carbide. The effects of machining parameters, such as pulse on time (TON), peak current (IP), flushing pressure (FP) and spark voltage on material removal rate (MRR) and surface roughness (Ra) of the material, have been evaluated. These parameters are found to have an effect on the surface integrity of boron carbide machined samples. Wear rate of brass wire increases with rise in input energy in machining of hot-pressed boron carbide. The surfaces of machined samples were examined using scanning electron microscopy (SEM). The influence of machining parameters on mechanism of MRR and Ra was described. It was demonstrated that higher TON and peak current deteriorate the surface finish of boron carbide samples and result in the formation of large craters, debris and micro cracks. The generation of spherical particles was noticed and it was attributed to surface tension of molten material. Macro-ridges were also observed on the surface due to protrusion of molten material at higher discharge energy levels.

Keywords

• Hot-pressed boron carbide
• MRR
• Ra
• Wire electrical discharge machining