Performance evaluation in dry and wet cutting conditions on Inconel 718 using a lathe CNC machine

This study compared the performance of dry and wet machining on Inconel 718, then optimised the wet machining parameters by examining tool wear and surface roughness. Inconel 718 is renowned for its exceptional hardness and high heat resistance, which makes machining challenging. This research aims to analyse the machining performance in dry and wet cutting, then optimise the machining parameters to achieve lower tool wear and surface roughness. The experiment was conducted using coated carbide inserts while studying three independent variables: cutting speed (Vc) varying from 30 to 100 m/min, feed rate (fz) from 0.03 to 0.07 mm/rev, and depth of cut maintained constant at 1 mm. Experimental results demonstrate that wet cutting achieved a 57.14% superior surface finish compared to dry cutting. However, the minimum tool wear rate was achieved with both cutting methods at different cutting speeds (wet at 30 m/min and dry at 100 m/min). The optimisation results showed that wet cutting conditions utilise a low Vc (30 m/min) but differ in fz, where a low fz (0.03 mm/rev) is optimal for achieving the best surface quality. In comparison, a high fz (0.07 mm/rev) is suitable for maximising productivity with better tool life. Findings show that wet cutting conditions produce low surface roughness (Ra) through low Vc and fz, while high fz is suitable for long cutting tool life.