Investigating the Machinability Performance of Novel DLC Coated WC Tool for CNC Green Machining (CNC Turning) of High Strength Steel Alloy (EN9) to evaluate the Machining Rate and Surface Finish and Compare with Uncoated HSS Tool

Abstract

Aim: To compare machinability performance of CrN coated Tungsten carbide (WC) Tool with uncoated Uncoated High Speed Steel Tool for cnc green machining (cnc turning) of high strength steel alloy (EN9) for improving machining rate and surface finish on Green Machining. Materials and Methods: The  high strength steel alloy material machining performance with use of noval Chromium Nitride (CrN) coated Tungsten carbide Tool is compared with Uncoated High Speed Steel (HSS) tool. Sample size calculated with the settings of  G-power 80%. Total number of groups is 2 and the sample size is 16 per group. Hence total samples involved are 32. Results: The results revealed that the average material removal rate improved from 5980.54249 mm³/min to 9226.341177 mm³/min by use of the noval Chromium Nitride (CrN) coated Tungsten carbide Tool  instead of conventional uncoated tool. Similarly the surface roughness reduced from 1.805125 µm to 0.472 µm. The Significance of P value obtained was 0.0277 (p<0.05) for  material removal rate and p=0.010 (p<0.05) for surface roughness observations. Conclusion: Within the limitations of the studies, the performance of high strength steel alloy with noval Chromium Nitride (CrN) coated Tungsten carbide Tool recorded a higher material removal rate (13.99%) than the conventional High Speed Steel Tool. Similarly, the proposed coated tool reduced surface roughness 59.75% than the conventional uncoated tool.