Chemical–Mechanical Polishing of Cemented Carbide Insert Surface for Extended Tool Life in Turning of GH4169 Nickel-Based Superalloy

Abstract

To extend the tool life of conventional uncoated grinding cemented carbide inserts (CUG inserts) in turning GH4169 nickel-based superalloy, chemical–mechanical polishing (CMP) is applied to appropriately treat the rake face of the CUG insert to address the defects including grinding burn, crack, and thermal deformation. The material removal rate (MRR) and the rake face roughness Ra of YG10 chemical–mechanical polished cemented carbide inserts (CMP inserts) corresponding to the six types of abrasives particles are investigated by applying the single factor method, and the diamond powder is the most suitable to polish YG10 inserts. Thus, CMP parameters are optimized using Taguchi method coupled with both the grey relation analysis and fuzzy inference. Furthermore, the comparison experiments of the cutting performance of the CUG insert and the CMP insert in turning GH4169 are carried out, under the same cutting condition, compared with the CUG insert, the average tool life of the CMP insert is increased by 35.92%. This study demonstrates that the CMP technique is an effective potential method to improve the surface integrity, the cutting performance and the tool life of conventional uncoated grinding cemented carbide inserts & tools in the machining of difficult-to-cut materials.