Investigation of machinability characteristics and chip morphology study in laser-assisted machining of Inconel 718

Laser-assisted machining (LAM) is a promising solution for all categories of difficult-to-machine materials like ceramics, metals and composites. Inconel 718, a difficult-to-machine material, is used in critical aero engine components. The objective of the study is to investigate its machining characteristics with low-cost cutting inserts using LAM. Therefore, in this paper, the machinability of this alloy has been investigated using physical vapour disposition-coated (TiAlN) carbide inserts in terms of cutting force, surface roughness, flank wear and chip formation in different range of cutting parameters. This investigation shows the improvement in machining performance of about 46, 36, 34, 50 44 and 68% for feed force, thrust force, cutting force, surface roughness and flank wear when compared to conventional machining (CM). For the criteria of benefit comparison, the detailed geometrical characteristic of produced chip and its morphology evaluation have been carried out under microscopic examination. The amplitude of this reduction is due to the maximum undeformed chip thickness of about 170 mu m in LAM compared to CM.