陶瓷空心球对金属结合剂金刚石砂轮性能的影响

Effect of ceramic hollow sphere on properties of metal bonded diamond wheel

通过添加陶瓷空心球并采用普通热压烧结法制备金属结合剂试样和金刚石砂轮,探讨了陶瓷空心球的形状、粒度及添加量对金属结合剂和砂轮性能的影响。结果表明:添加陶瓷空心球后,金属结合剂胎体试样的抗弯强度和硬度均有所下降,但其受陶瓷空心球粒度的影响很小;含金刚石的胎体试样与金属结合剂胎体试样相比,抗弯强度降低了0.84～7.01 MPa,约为1%～8%。胎体试样的断口形貌显示陶瓷空心球体形状规则,均为圆形,能较均匀的分布在金属结合剂胎体之中,可以为金属结合剂胎体提供一定的孔隙空间;添加适量的陶瓷空心球能提高砂轮的磨削效率,磨削YG8硬质合金工件时能提高8%～43%,其中含质量分数3.75%陶瓷空心球的砂轮磨削效率最高,相比于致密砂轮提高了43%。

By means of adding ceramic hollow spheres and by adopting hot-pressing sintering to prepare metal bond sample and diamond wheel, this research discussed the effect of shape, particle size and addition amount of ceramic hollow spheres on the performances of the metal bond and the metal bonded wheel. The results showed that, the bending strength and hardness of metal bond sample were declining with the increase of the addition amount of ceramic hollow spheres, but were not very much influenced by particle size of ceramic hollow spheres. Under the same porosity, the bending strength of matrix sample containing diamond was decreased by O. 84 - 7.01 MPa compared with that of the bond sample, a decrease of about 1% ~ 8%. The fracture morphology of sample showed that ceramic hollow spheres were all round and their shape were regular, so they could be evenly distributed in metal bond and provide certain pore space for it. The optimal addition amount of ceramic hollow spheres of 3.75% （mass fraction） could improve grinding efficiency of wheel by 8% -43%, when grinding YGS, which was higher by 43% than compact grinding wheel.