Effect of Deep Cryogenic Treatment on Machinability of Titanium Alloy (Ti-6246) in Electric Discharge Drilling

Abstract

Currently there is a vital need for cost effective machining processes for titanium alloys. Electrical discharge machining (EDM) is used quite extensively in machining titanium alloys due to its favorable features and advantages. This paper investigates the effect of deep cryogenic treatment (DCT) on machinability of Ti 6246 alloy in electric discharge drilling (EDD) by conducting experimental investigations on the production of 10 mm diameter blind holes with electrolytic copper tool. An attempt has also been made to compare the production accuracy of holes drilled in deep cryogenically treated Ti 6246 (DCT Ti 6246) alloy and nontreated Ti 6246 alloy in terms of surface roughness and overcut. The result of study reveals the higher material removal rate (MRR) and wear ratio (WR), lower tool wear rate (TWR) in case of EDD of DCT Ti 6246 alloy workpiece as compared with nontreated Ti 6246 alloy workpiece. Also superior production accuracy of holes is reported while EDD of DCT workpiece.