Experimental Study On High Efficient Belt Grinding Of Titanium Alloy

Titanium alloys are widely used in aeronautics, astronautics, chemistry and oceanics, because of its excellent physicochemical properties such as high specific strength, steady elevated temperature property and great inoxidability. But titanium alloy is also a typical kind of difficult-to-cut material for its low heat conductivity, low elastic modulus and high chemical activity. Belt grinding is a new kind of process which combines grinding with polishing. Its advantages of high efficiency, cold condition grinding can solve the cutting problems of titanium alloy such as surface ablation, low machining efficiency and short tools life. So belt grinding certainly will become a new-style processing technique of titanium alloy.The paper employs belt in the grinding process of titanium alloys, and develops the equipment. Comparisons are made for the machining efficiency, surface integrity, cutting force and tool costs between milling and belt grinding. The result shows that:(1) The comparison of machining efficiency is made between both the processes of milling and belt grinding. The result shows that, the machining efficiency of belt grinding is much higher than that of milling. At the same time, on the premise of ensuring the tools life, the machining efficiency of belt grinding could be 10 times longer than that of milling.(2) The grinding force is measured and analyzed. The result displays that, the grinding force is far below the milling force for the identical machining efficiency. For the reason, the belt grinding has great potential during machining of thin-walled parts.(3) By the comparison of tools costs, it is found that belt grinding costs 2-4 times higher than milling under the optimized parameters.(4) Under the same machining circumstance as without cooling and identical efficiency, the surface roughness such as Ra<1.6μm could be acquired in both the process of milling and belt grinding. However, no remarkable change for the belt grinding could be observed in terms of surface microstructure and microhardness of the machined parts. A metamorphic layer with the thickness of about 50μm exists in the milling parts.(5) In order to improve the belts life, the wear mechanism of the belt is researched. The optimum processing parameters are therefore provided for the industrial belting grinding with high efficiency and high quality.