Performance test of coated HSS tool with respect to thrust force, torque and surface integrity on customized EN8 specimen

The scope of this presented work involves the study on effect of cutting speed and feed rate of a customized coated high-speed steel (HSS) tool on thrust force, torque and surface integrity. The standard European norms 8 (EN8) specimen is selected, and its hardness is varied as 15, 20 and 25 Rockwell hardness on the Rockwell C scale (HRC) to make ease of research. Four tools with the composition of R1, R2, R3 and R4 were chosen. Maximum of 67 N thrust force and 8.9 µm surface roughness was obtained at 12.57 m/min cutting speed for 25 HRC specimen. Lower value of thrust force and surface roughness was observed for tool 2. Low as 1.90 µm surface roughness was noticed for 15 HRC specimen when the speed of cut given is 1500 rpm and 1.8µm at a feed rate of 5 mm/rev. A minimum thrust force of 6 and 8 N was observed for feed rate and cutting speed of 5 mm/rev and 62.86 m/min respectively. It was noticed that, thrust force increases gradually when the rate of feed enhanced and is reduced with respect to increase in cutting speed. The tool shows poor performance at the 25 HRC specimen at maximum operating conditions. Tool 2 gives better performance for 15 and 20 HRC of EN8. Thus, tool 2 with R2 composition can be employed till the hardness level of 20 HRC without losing quality of the work.