The Wear Prediction And Study Of Cemented Carbide Tool For Cutting Ti6Al4V In High Speed

Titanium alloy material has been widely used in many fields, such as aerospace, aviation and many other fields because of its high strength, good corrosion resistance, high heat resistance and so on. However, titanium alloy is one of the typical material difficult to machining because of the characteristics of small thermal conductivity, strong chemical activity and low elastic modulus. However, the poor machinability and the induced rapid tool wear during cutting has limits the further wide application of titanium alloy, and the tool wear not only increases the tool consumption, but also reduces the machining quality and productivity. In this thesis, first, the temperature measuring system is developed with Lab VIEW. Second, Cemented Carbide tool wear is studied by related experiments in high speed turning Ti6A14 V. Then, the key technology and the realization of methods for simulation of tool wear are discussed; the tool wear finite element model for cutting titanium alloy in high speed is established with MSC. Marc, and the simulation results are verified through the tool wear experiments. The effect rules of cutting parameters on tool wear are studied, and the reasonable parameters range of high speed cutting of titanium alloy is given. In the end, the influence of tool wear on the machining process is studied. This study is of great significance to reduce the cost of processing, improve the cutting efficiency and optimize the cutting tool geometry. The contents of this paper are as follows:(1) The cutting temperature acquisition system is developed according to the requirements of the tool wear experiment of high speed cutting titanium alloy. This thesis describes the principle of natural thermocouple measuring the temperature, and then discusses the method of calibration, and gives the method of rapid calibration of the natural thermocouple and the compensation method of the cold end. The use of LabVIEW to achieve temperature signal acquisition, processing, analysis, reading and storage, natural thermal calibration and other functions.(2) Research on the key technology of tool wear simulation, including the establishment of the constitutive model, friction model and geometric model of material, a finite element model of high speed cutting of titanium alloy is established. By cutting experiment, the tool wear process in HSC titanium alloy is discussed. Combined with related parameters of test and simulation, the tool wear rate model is obtained.(3) By taking increasing the heat transfer coefficient between the tool – chip and elements remeshed method, a series of problems are solved such as unstable tool temperature field and tool wear morphology updating etc. The tool wear finite element method(FEM) model is established and verified through cutting experiments.(4) The effect rules of cutting parameters on tool wear are studied, and the reasonable parameters range of high speed cutting(HSC) of titanium alloy is given. The tool rapid wear process in HSC is disclosed by studying the development of crater morphology, meanwhile, the influence law of tool wear on cutting temperature, stress and strain is analyzed.