Cutting Simulation And Design Of Gradient Self-lubricating Ceramic Tool

The self-lubricating gradient ceramic tool material is a new composite materialwith the characteristics of gradient function, self-lubricating effect and ceramiccharacteristics and the function of excellent heat-resistant, thermal insulation andalleviated thermal stress. The material has improvement of the brittleness and thermalshock resistance on the conventional ceramic materials. Currently, the gradientself-lubricating ceramic tool material has been successfully designed and sintered, andthe mechanics performance testing, microstructure analysis and frictional wearexperiments have been done, but the theoretical studies about turning is not yet clear.Five kinds of finite element softwares were listed and introduced briefly. Interalstress distribution of Al₂O₃/TiC/CaF₂tool material was analysed by the finite elementsoftware ANSYS, layers of the stress was defined to the tool materials as the additionalload. The cutting performance of Al₂O₃/TiC/CaF₂tool was simulated by DEFORM. Thekey technologies with constitutive equation, heat conduction equation, contact frictiontype of tool-chip, mesh generation were introduced, the physical property parameter ofthe tool material was calculated by determining the composition distribution model oftool materials, and orthogonal cutting model was simplified establish.The cutting process of gradient tool and homogeneous ceramic tool materialswhich had the same materials with the surface materials of gradient tool cutting45#steel were simulated. Cutting temperature and cutting force of different cutting toolmaterials wereanalysed and compared. The results showed that the gradient ceramic toolmaterial had better machinabilitythanhomogeneous ceramic tool materials, andprovedthat the design theory of gradient self-lubricating ceramic tool material isreliability. The effect of solid lubricantCaF₂was analyzed in the gradientself-lubricating ceramic tool materialsAl₂O₃/TiC/CaF₂,whichwaslubricant from brittleinto plastic when cutting temperature was near504℃.The impact of the cutting speed, cutting depth, tool cutting edge radius on thecutting process was analysed. The seven layers tool material has a best superficialcharacteristics under V=169m/min in the range of82m/min to169m/min. The maincutting force of seven and nine layers tool materials declined in the cutting force, andthe cutting temperature of seven and nine layers tool materials rises very slowly underthe cutting depth is more than0.3mm in the range of0.2mm to0.5mm.When the tool cutting edge radius is in the range of0.8mm to1.2mm, the superficial characteristics ofthe seven layers tool material has little effect, but the nine layers tool materials has agreat impact on the cutting force.Al₂O₃/TiC/CaF₂tool materials were sintered using a method of vacuum hotpressing. Mechanicalpropertytesting and the cutting experiments were done.