【摘要】 借助X射线衍射方法测量了反应烧结碳化硅(RBSiC)材料的磨削表面的残余应力状态,并根据断裂力学评价了磨削引入的裂纹尺寸,分析了RBSiC的弯曲强度受磨削引入裂纹和残余应力的影响.研究表明,由于磨削过程中与磨削方向有关的机械载荷占主导作用,使磨削后的表面残余应力具有方向依赖性.砂轮轴向进给从0.90μm/s增加到1.35μm/s,磨削表面的残余压应力数值降低,计算得到的磨削引入的裂纹尺寸增大,导致强度下降.更多还原

【Abstract】 The effect of surface residual stress and crack on bending strength of reaction bonded silicon carbide(RBSiC) after grinding was investigated.The residual stress of the ground surfaces were determined using X-ray diffraction.The sizes of strength controlling cracks were assessed using fracture mechanics approach.The investigations show that mechanical load,which has relation with grinding direction,phays a dominateve role in the grinding processes.and the measured residual stresses have a direction dependency.With increase of down feed from 0.9μm/s to 1.35μm/s,the bending strength is reasonably correlated with the surface residual stress and crack size.更多还原