Machining of Tungsten Heavy Alloy under Cryogenic Condition

Abstract

The alloys of Nickel, Cobalt, Titanium, Tungsten belongs to the group of super hard alloys among them, tungsten is more used in industries as it is cheap when compared to other alloys and is easy to manufacture. The machining of super hard alloy tungsten is very difficult and costlier process as it requires harder cutting tools. Though carbide tools are extensively used, these take high machining time and tool failures which lead to decrease in productivity. To overcome the above, advanced techniques are being practiced in machining of tungsten alloy, one such technique is cryogenic cooling. Nitrogen is more preferable in machining to dissipate heat generated because it is cost effective, safe, non flammable and environmental friendly gas, in addition to that it cannot contaminate work piece, no separate mechanism for disposal. An experimental investigation has been carried out on machining of tungsten heavy alloys under cryogenic environment. The material removal rate, surface integrity and cutting forces were studied for both conventional coolant as well as cryogenic coolant. The chip morphology was measured for evaluation of shear stress and shear strain under cryogenic machining.