Machinability analysis of high strength materials with Cryo-Treated textured tungsten carbide inserts

In some critical applications, Precipitation Hardened PH stainless steel 17Cr-4Ni is used in the hardened condition. After heat treatment, machining is difficult but possible with special attention. In this study, an effort has been taken to model the machinability evaluation of 17-4 PH stainless steel using Cryo-Treated textured tungsten carbide inserts via Response Surface Methodology (RSM). Different machining characteristics such as tangential force, surface roughness and vibration components in three axes were considered as responses. In this present investigation, three-dimensional (3D) surface plots were used to study the effect of process parameters such as machining speed, feed, and machining depth with their interactions. The study revealed that the combination of higher machining speed with lower feed results better surface finish and also the machining depth has a significant effect on surface roughness R-a. Lower machining speed, lower feed and higher machining depth induced more vibration; however, the vibration was reduced at higher feed. The machining variables were optimized using response surface methodology desirability approach. Experimental results were in close conformity with the results of developed mathematical models, and optimal parameter was obtained through response surface method overlay plot.