金刚石纤维砂轮的制备及磨削表面质量研究

Preparation and Grinding Surface-quality of a New Diamond Fiber Wheel

提出和制备一种新型结构的金刚石纤维砂轮.利用粉末注射成形技术和真空钎焊技术制备出长径比大、金刚石把持力大的金刚石纤维,通过在砂轮胎体材料中添加造孔剂引入多孔隙结构以提高容屑空间,将金刚石纤维在砂轮胎体材料中进行有序排布,对砂轮胎体材料进行热压成形制备出新型金刚石纤维砂轮.新型金刚石纤维砂轮制备后,开展其与普通树脂结合剂金刚石砂轮在相同试验条件下的磨削表面质量研究.试验结果表明：金刚石纤维砂轮磨削表面质量优于普通树脂结合剂砂轮,加工表面完整性较好,宏观裂纹和表面损伤相对较少;当进给速度为40 mm/s,磨削深度为40μm时,金刚石纤维砂轮磨削表面粗糙度为0.52 μm,比普通树脂结合剂砂轮的磨削表面粗糙度降低了20％;相同试验条件下,新型金刚石纤维砂轮的磨削表面残余应力下降了8％～12％,金刚石在磨削过程中主要经历了完整、小块破碎、大块破碎、磨耗等正常磨损形式,其具有较长的使用寿命.

It is aimed at developing a new diamond fiber wheel in order to overcome shortages of conventional diamond wheels.The diamond fibers are fabricated by combining powder injection molding with vacuum brazing,which havea large aspect ratio and diamonds grits pullouts cannot happen due to the presence of the chemical bonding.These diamond fibers can be artificially ordered so as to have the desired arrange parameters,and then suppressed with resin bond materials to prepare a new diamond fiber wheel.And it compared the ginding surface-quality of thenew diamond fiber wheel with that of conventional resin bond diamond wheel in machining the WC/12Co coating.The experimental test indicated that the quality of the machined work-piece surface is better than that machined by the conventional resin bond diamond wheel,the surface roughness is 0.52 μm when the feed speed is 40 mm/s and the depth of grinding is 40 μm,and the residual stress of ground surface decreases by 8%-12%,the diamonds mainly occur integrity,micro-fracture,fracture and rubdown in grinding process,the diamond fiber wheel has long service life.