Research on precision dressing of resin-bonded arc-shaped diamond grinding wheel via tantalum metal.

Abstract

High-precision curved optical components are widely used in aerospace, precision molds, medical devices, and other fields, which require higher profile accuracy and grinding stability in the resin-bonded arc-shaped diamond grinding wheels employed for processing these workpieces. However, the green silicon carbide (GC) dresser wears easily during the dressing process, leading to large arc profile errors and insufficient exposure of abrasive grains, which limits further improvements in grinding wheel performance. Therefore, this paper proposes using high-melting-point metal tantalum (Ta) as a dressing tool for resin-bonded diamond grinding wheels and investigates the mechanism of tantalum dressing using Raman spectroscopy, X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS). The results indicate that during the dressing process, tantalum reacts with carbon and oxygen on the grinding wheel surface, which leads to the formation of new phases, including TaC, TiC and Ta₂O₅. The transition layer formed by these reaction products at the interface of the abrasive materials exhibits both lubrication and thermal barrier functions, effectively preventing diamond graphitization and enhancing the mechanical stability of the abrasive structure. Based on this, to further verify the effectiveness of tantalum in dressing arc-shaped diamond grinding wheels, a comparative experiment was conducted using tantalum and GC grinding rods. The dressing performance of the two tools was systematically evaluated through both quantitative and qualitative analyses of the grinding wheel run-out error, form error, and surface morphology. Experimental results show that using tantalum as the dressing tool significantly enhances grinding wheel profile precision, reducing run-out error from 62.4 μm to 4.3 μm and limiting form error to 7.5 μm. Compared to GC grinding rod dressing, tantalum dressing reduces run-out and form errors by 65.87 % and 52.83 %, respectively, clearly demonstrating the advantages of tantalum in enhancing shape accuracy. Moreover, tantalum dressing markedly improves the grinding wheel's surface characteristics, facilitating the full exposure of cutting edges on abrasive grains, which is essential for improving grinding performance.