Design and synthesis of an Al2O3 fiber strengthening (Ti,W)C sandwich cermet tool by spark plasma sintering

Abstract

A sandwich structure with a sound design helps the cermet tool's surface form residual compressive stress, which enhances the tool's cutting and mechanical capabilities. In this study, a sandwich cermet tool has been created and constructed with Al2O3 fibers added to the middle layer of the (Ti,W)C sandwich cermet tool. The (Ti,W)C sandwich cermet tool's physical model is constructed, and using FEM modeling, an exploration was undertaken to examine how the residual stress is affected by the Al2O3 fiber content and thickness of the middle layer. To gain a deeper insight into the cutting performance of the sandwich cermet tool, dry cutting trials are carried out. The (Ti,W)C sandwich cermet tool's mechanical properties are greatest when the middle layer has an Al2O3 fiber content of 5 vol% and is 1 mm thick. Under these conditions, the residual compressive stress on the tool's surface is −86.2 ± 7.41 MPa. Flexural strength of 1005.10 ± 50.55 MPa, fracture toughness of 8.25 ± 0.46 MPa·m1/2, and Vicker's hardness of 21.07 ± 0.46 GPa are all higher than those of a homogeneous cermet tool by 26.26 %, 6.6 %, and 3.9 %, respectively. When compared to the data recorded with the (Ti,W)C homogeneous cermet tool, the cutting force, cutting temperature, friction coefficient, and surface roughness all indicate a decrease because of the residual compressive stress that is still present on the surface of the (Ti,W)C sandwich cermet tool. Additionally, this influence caused by stress increased the cutting distance by 15.38 %.