Dry Machining of Superalloys: Difficulties and Remedies

These Super alloys sustain its strength at high temperature and pressure conditions. Such materials have great demand in aerospace industry, marine industry, and nuclear power plants. It is particularly used in the hot sections like engines, because of their high strength and corrosion resistance at high temperature and pressure but they are the most difficult to machine materials. Their high strength possesses large amount of heat generation while machining, which reduce life of tool. Strain rate sensitivity, work hardening and precipitation hardening of material leads to more tool wear. Surface integrity obtain while machining of superalloys is poor. Poor surface finish and high residual stresses are the main causes of failure of these material components. Cutting fluid apply at high pressure in chip forming zone. It affects environment and create problem of disposal of cutting fluid. So dry machining should be employed. This article is about the difficulties occurs during dry machining and suggestions to overcome problems during dry machining. Dry machining performed at high speed with special coated carbide tool inserts which helps to avoid the rapid tool wear. This paper discusses the capabilities of dry machining of super alloys using specially coated carbide tool inserts.