Cutting Parameters Modeling And Assessment Of Micro Diamond Grain Based On 3D Detection And Reconstruction

Precision grinding mainly depends on abrasive grain protrusion and shape on grinding wheel working surface, but the grains cutting parameters are difficult to be identified due to their 3D irregular protrusion form and random distribution. What’s more, researchers usually only consider 2D cutting parameters of micro grains. Hence, a 3D intelligently recognizing and extracting method was proposed based on the actual measured data of the grain protrusion on grinding wheel working surface. And a 3D cutting parameters model was built by sectioning the micro protrusion topography to several sections along grain cutting direction. In order to test the 3D grain cutting parameters of grinding applications, mechanical dressing, electrical discharge dressing by a fixed copper electrode and a rotated iron electrode were employed to dress the #46 bronze-bonded diamond grain wheel, then using the wheels dressed by different dressing conditions to perform a mechanical and discharge micro grinding of aluminiumcarborundum and S136 H die steel. Finally, the mechanism of action was studied that how 3D grain cutting parameters influence grinding ground surface quality combined with grinding process. Specific research results are as follows:(1) Compared with 2D intelligently recognizing and extracting method, 3D method can recognize and extract the 3D curve grain boundary more precisely, and enhances grain protrusion height and volume by 24.9% and 40.6%. Micro grain cutting parameters of 3D characterization can reflect the grinding performance more accurately, and decreases rake angle by 58.1% and enhances relief angle by 232.0% than 2D characterization.(2) Electrical discharge dressing by a fixed copper electrode improves the dressing rate and efficiency to 263.32 times and 7.27 times compared with mechanical dressing. Compared with electrical discharge dressing by a fixed copper electrode and mechanical dressing, electrical discharge dressing by a rotated iron electrode, which taking advantage of thermochemistry and the catalytic effect of iron, enhances diamond grain rake angle by 14.81% and 19.40%, enhance stiffness by 46.19% and 59.05%, what’s more, decreases relief angle, tool cutting edge angle and tool minor cutting edge angle by 30.74% and 36.77%, 57.67% and 66.56%, 49.36% and 67.74%.(3) Compared with mechanical dressing and electrical discharge by a fixed copper electrode, electrical discharge dressing by a rotated iron electrode improves the achieve grain numbers and achieve grain volume by more than 3 to 5 times and 10 to 14 times for the depth of cut of 5 μm, and decreases the ground surface roughness of aluminium-carborundum and S136 H by 37.66% to 79.09% and 45.89% to 82.5%, respectively. Hence, it can drastically improve the quality of workpiece ground surface by enlarging achieve numbers, achieve grain volume, grain rake angle, stiffness and decreasing relief angle, tool cutting edge angle and tool minor cutting edge angle.(4) The electrical discharge dressed #46 diamond grain wheel by a rotated iron electrode was used to mechanical and discharge micro grinding, it is found that type II discharge micro grinding(conductive workpiece connects the positive of power supply and the diamond grain wheel connects the negative) decreases duration of discharge by 28.03% and improves discharge electric current by 44.85% compared with type I discharge micro grinding(conductive workpiece connects the negative of power supply and the diamond grain wheel connects the positive). What’s more, type II discharge micro grinding decreases wordpiece ground surface roughness by 20.11% and 25.92% compared with mechanical and type I discharge micro grinding, and Ra reach to 66.7 nm.