Study On La₂O₃-SiCw-Ti（C,N）-Co Composite Ceramic Tools With Less Binder Phase Of Preparation And Cutting Performance

In this paper, the Ti(C,N)-Co-Si Cw-La2O3 cermet was prepared by spark plasma sintering technology system.By means of metallographic microscope(OM), scanning electron microscopy(SEM) and analysis of optical microscopy and universal tensile testing machine, hardness testing equipment.Effect of sintering temperature and adding phase component ratio on microstructure and mechanical properties of metal ceramic were studied. The sintering mechanism and add phases toughening mechanism cermet was analyzed. The effect of different angle and the binder phase on the surface roughness of metal ceramic tool cutting force and surface was studied. Performance and tool wear mechanism was studied, which Ti(C,N)-Co-Si Cw-La2O3 ceramet tools were continuous cutting 45 steel.The detailed research results are shown as follows:1) Sintering pure submicron Ti(C, N) powder successively different content of Co, Si C whiskers, La2O3 rare earth oxides, the use of spark plasma sintering at a temperature of 1400℃ ~1800℃ range of prepared sample,wherein,Ti CN-Co material in the sintering temperature 1600 ℃ 5wt% Co addition amount of the sintering density, flexural strength and Vickers hardness was 815 MPa and HV101505; Si Cw-Ti CN-5Co material at a sintering temperature of 1800℃, Si Cw content at the time of 1wt% sample of the most dense and flexural strength and Vickers hardness of 1150 MPa, respectively, and HV1630; in Si Cw-Ti(C, N)-5Co cermets add content 1% La2O3. Further improve the degree of densification and sintering temperature in the mechanical properties of materials under 1800℃ higher flexural strength of 1463 MPa, Vickers hardness HV1670.2)After the tool 3?~11?angle within the range of cutting parameters remain unchanged, with the rear tool angle increases, the cutting force and surface roughness were tested first increases and then decreases the variation. When 7? after the tool angle, suffered minimal cutting forces. When the angle of the surface roughness at the 11?minimum. In addition phase, when added to the small Si C whisker ceramic binder phase metal, cutting force and surface roughness somewhat larger, but after adding La2O3, cutting force and surface roughness of the material is greatly reduced.3)Comparative study of three different morphologies wear reinforcements less binder phase cermet cutting tools, wear wear curve typical graph of the three tools basically consistent. Where Ti(C, N)-5Co reach blunt standard cutting distance of about 1000m; when adding Si C whiskers Ti(C, N)-5Co blunt standard cutting tool to reach a distance of 1300 m, Si C whiskers added to enhance the tool strength, increased wear resistance; and continue adding the distance between the tool cutting La2O3 reached after blunt criteria is 1600 m, La2O3 is added to reduce the material cracks, voids, wear resistance is further improved.