Research On The Cutting Tool Materials Of Ti(C,N)-based Cermets And The Cutting Performance

Ti(C,N)-based cermets as a new type cutting tool composite materials arerapid developed in recent years. It not only has good comprehensive mechanicalproperties, but also has excellent physical performance such as low density,highthermal conductivity, and low friction coefficient.The cermets have alreadypartially supplanted cemented carbide for high speed cutting and halfmachining,finishing in cutting processing field,and suitable for dry cutting.In thisthesis,the cutting properties of the Ti(C,N)-based cermets were analyzed andpredicted by the finite element method (FEM) simulation technology.Thecorrectness of the simulation were verified by cutting experiments,which canprovide reference for choosing reasonable geometric parameters of Ti(C,N)-basedcermets cutters.The two groups of Ti(C,N)-based cermets materials with the different originalTiC particle size were prepared via the method of powder metallurgy and vacuumsintering process. The phase, microstructure and components of the two kinds ofcermets were analyzed respectively with X-Ray Diffraction (XRD), ScanningElectron Microscope (SEM) and Energy Disperse Spectroscopy (EDS),and testedtheir room-temperature mechanical properties.The comparative results show that:the cermets (Cermets B) were prepared with the original powder of nano-TiC thatmicrostructure grain fine and uniform.The bending strength and hardness are higherthan the cermets (Cermets A) that micron TiC as original powder.Three-dimensional cutting finite element model was built in DEFORM finiteelement simulation software for simulating different relief angle turning process ofTi(C, N)-based cermets cutters. Analyze the simulation results of effective stressfield,temperature distribution and wear reveal that the best clearance angle of thetwo kinds of homemade cermets cutters using different TiC original particle size is5°.The cutting experiment of the two kinds of Ti(C,N)-based cermets tools,whichwere made with micron TiC and nano-TiC powders,against work-piece of AISI1045carbon steel were carried out.The experimental results show that the bestdurability of the two kinds of cermets cutting tools are the clearance angle5°,which proves the correctness of the prediction of the finite element simulation.The flakworn surfaces morphologies of the two kinds of Ti(C,N)-based cermets cuttingtools were observed by SEM,at the same time, the failure types and wearmechanisms were investigated.At high speed turning experiment, the primary wearbehaviors of the homemade Ti(C,N)-based cermets cutters are oxidative wear anddiffusion wear.