Study On Torus-shaped Diamond Grinding Wheel Adaptive Form-Truing For Precision Grinding Of Curved Surface Steel Core

The complex optical freeform surface is gradually applied to the optical system instead of the spherical and aspherical surface due to the optical system becomes more and more miniaturized and high-performance. Meanwhile, the mold mass production of the ultraprecision optical components is a trend in the optical manufacturing industry. But, how the diamond grinding wheel profile adapted to the curve surface contour is a bottleneck in the precision and high efficient grinding of the complex freeform surfaces molded steel core. Thus, a curved torus grinding wheel designed adapted to the freeform surface contour was proposed along with the form-truing of the curved torus grinding wheel profile. And the tool location algorithm for the torus diamond wheel was proposed to grinding of the freeform surface. Through experimental study on removal mechanism between the grinding wheel and the workpiece, the dynamic simulation model of grinding wheel profile errors was built in grinding of the freeform surface. The purpose of the study is to realize intelligent complex surface precision grinding.Research result shows that the actual working area of the curved torus wheel profile is taking up about 60% of the thickness of the grinding wheel, while the arc one is about 30%~50%. The thickness and the height of curved torus wheel profile are 10 mm and 2 mm, respectively. And the wheel profile mean error is less than 27 μm, thus the form-truing craft is effective. Besides, the dynamic simulation shows that the curved torus wheel profile has self-repairing in grinding process of freeform surface, which is called the adaptive form-truing ability, and the result shows that the wheel profile accuracy was improved by 14%, while the arc one has not the ability when grinding the same freeform surface. Experimental result shows that the curved torus wheel profile mean error reduced from 21.5 μm to 15.7 μm during the grinding of curved surface steel core, Thus the wheel profile can self-repairing online in grinding process. Experimental results show the freeform surface form error was 15.1 μm with area of 30 mm×6 mm, and the surface roughness is 50 nm. All above, the form-truing craft and the the tool location algorithm for curved torus wheel can achieve high efficiency precision grinding of complex surface.