Experimental Investigation on Precision Electrical Discharge Dressing of Small-diameter Bronze-bonded Fine Grain Grinding Wheel

doi:10.3901/JME.2019.03.199

Abstract

Abstract: Fine grain bronze-bonded diamond grinding wheel is usually used in ultra-precision machining of hard and brittle materials, but it is difficult for dressing because of the high hardness of the diamond and the strong adhesion of bronze-bond. Inner-flushing curved electrodes are used in electrical discharge dressing of W10 fine grain bronze-bonded diamond grinding wheel. The experimental platform is set up and three different degrees of inner-flushing curved electrodes are designed. The Keyence VHX6000 3D microscope, roughness profile measurement instrument, CCD laser displacement sensor and meter and SEM are employed to investigate the surface micro topography, profile of dressed grinding wheel and grinding test. It is found that improvement of inner-flushing of 60°-curved electrode is best and the protrusion of diamond grains on surface of after dressing is clearly observed with uniformly distribution and unburned during electrical discharge dressing; the minimum circular runout error can reach 1.7 μm, 1.8 μm and 1.8 μm. It is also verified by grinding experiment that surface roughness by grinding wheel with 60°-curved electrode is Ra2.273 nm, which can reach the high quality level of ultra-precision mirror grinding.

Key words: circular runout error, curved electrode, electrical discharge dressing, fine grain grinding wheel, surface micro topography

CLC Number:

TG661

YU Jianwu, HE Lihua, SHANG Zhentao, LUO Hong, LIANG Qihua. Experimental Investigation on Precision Electrical Discharge Dressing of Small-diameter Bronze-bonded Fine Grain Grinding Wheel[J]. Journal of Mechanical Engineering, 2019, 55(3): 199-207.

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