On the formation of Ti2AlN MAX phase coatings and improvement in tool life by superimposing on tungsten carbide cutting tool for machining Ti-6Al-4V alloys

This paper presents the development of (002) textured Ti2AlN coated wear resistant tool utilizing reactive magnetron co - sputtering. The Ti2AlN coating was developed in two different Argon, Nitrogen ratios such as 64:3 and 64:4, the influence of these parameters was identified using crystallographic, microstructural, mechanical and tribological studies. Experimental studies were performed to compare the cutting force as well as the tool life of superimposed Ti2AlN tool with a commercial tool by turning titanium alloy (Ti-6Al-4V). Results from the experimental analysis revealed an 80-85 % increase in hardness, a 13-20 % decrease in wear rate and a 27 % increase in tool life for Ti2AlN coated cutting tool. According to chip morphology, there is a 12 % increase in shear angle, 43 % and 51 % decrease in friction angle and coefficient of friction respectively. The nanomechanical studies were performed which show a maximum hardness of 29.12 +/- 5.4 GPa and minimum wear rate of 10.078 x 10(-9) mm(3)/mN.m(-1) for superimposed Ti2AlN.