| As structure materials, titanium alloys are widely used in aerospace industry due to their high specific strength, good heat resisting property and high corrosion resistance property. However, titanium alloy is well known as a difficult-to-machine material because of low thermal conductivity, low elastic module, and high chemical activity. The surface of the workpiece is easy to be burned in the grinding process. High speed grinding is an advanced modern grinding technology, which can achieve high grinding efficiency, high grinding ratio and good surface integrity. Therefore it is important to apply high speed grinding technology in the machining process of titanium alloy. The machinability of titanium alloy is improved.Based on the experiments of high speed grinding of titanium alloy with CBN wheels, the main work are as follows:(1) Vitrify-bonded CBN grinding wheels, monolayer plated CBN grinding wheels and monolayer brazed CBN grinding wheels were used in the grinding process of TC4 titanium alloy, respectively. Then, the influence of the grinding wheels and the machining parameters on the grinding forces, the grinding temperature and the specific grinding energy were analyzed. The surface integrity under different grinding conditions was also discussed. The effect of the average chip thickness of the abrasive grain on the grinding forces was investigated, which could provide a guide to improve the grinding efficiency of titanium alloys.(2) Based on the analysis of the experimental results, the grinding parameters were optimized The high efficiency profiled grinding experiment was carried out to machine titanium alloy with the wheel speed of 150 m/s and the materials removal rate of 100 mm~3/(mm·s). The results indicate that no burned phenomenon happened and good surface quality has been obtained.
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