Effect of Ni-binder, PECS and MQL on face milling of Ti-6Al-4V

The utilization of Ti-6Al-4 V for several engineering applications is usually not viable, due to the high cost associated with its machining. The poor thermal conductivity and high strain rate of Ti-6Al-4 V results in high concentration of stress at the cutting tool edge, leading to rapid tool degradation and subsequently poor surface integrity. This significantly affects the overall machining cost. Notwithstanding, the high hardness and toughness of WC-Co cemented carbide tools give them some leverage in Ti-6Al-4 V machining, but concerns over unstable prices, scarcity, toxicity and rapid degradation of cobalt have led investigations into alternate binder metals. This study investigates the effect of nickel as an alternate WC binder, pulsed electric current sintering (PECS) and minimum quantity lubrication (MQL) on mechanical properties and performance characteristics during face milling of Ti-6Al-4 V. The mechanical properties of the cutting tool inserts assessed were hardness and fracture toughness, while performance characteristics assessed were cutting forces, flank wear of the cutting tool inserts and surface roughness of the machined Ti-6Al-4 V surfaces.