Experimental Study and Finite Element Analysis of the Impact of Tool Edge Geometry in Orthogonal Machining of Super Alloy Inconel 718

The demand for super alloys of extraordinary hardness and confrontation for automobile and aeronautical applications. However, the metal cutting of super alloys like Inconel 718 are very tough because of various factors like the formation of built up edges, increased machining forces, increased machining temperature, high tool wear, etc. These reasons may lead to poor surface finish, reduced tool life and improper chip formation. The edge dimensions of tool inserts play a vital in the orthogonal machining of aerospace super alloys which are hard to machine alloys. This tool insert geometry also directly have an influence in chip formation mechanism which in turn panels the chip morphology. In this paper, orthogonal machining test on Inconel 718 have been conducted to examine the impression of the edge geometry in machining outputs like surface roughness, machining forces, temperature and cutting insert wear. The consequence of machining constraints are also studied on the above mentioned outputs. Cutting edges are modified using Wire EDM technique. Silicon Nitride and Cubic Born Nitride tool inserts were used for orthogonal machining. This paper is mainly focused to compare the machining outputs beforehand and later alteration of tool insert geometry. The tool cracks and built up edge formation by means of microscopic images were inferred and examined. The parameters which are to be varied in the experiment are defined by L9 orthogonal array. The metal cutting was developed in AdvantEDGE software to analyse conforming stress dissemination.