多数零件的失效行为，并不是因为零件受到超过其屈服极限的力冲击作用而产生的，而是在小于其屈服应力的载荷反复作用下产生的，因此如何有效提高零件抵抗低应力多冲碰撞能力具有重要的现实意义。通过对0Cr18Ni9试件和具有Ni基激光熔覆涂层的0Cr18Ni9试件进行多碰试验，采用网格坐标法记录材料表面的塑性变形情况。试验结果表明，在远低于材料屈服强度的载荷多次碰撞下，0Cr18Ni9试件和具有Ni基激光熔覆涂层试件都发生可测的塑性变形，且后者的变形量远小于前者。因此对零件采用先进涂层技术，是一种提高零件抗多冲碰撞能力的有效途径。

Most failure behaviors of machine parts were not caused by impact force beyond the yield limit, but repeated force under yield limit. Therefore, the research on how to improve the ability of resisting low repeated impact has important practical significance. In the paper, a repeated impact load experiment on 0Cr18Ni9 sample and 0Cr18Ni9 sample with Ni based laser cladding coating were carried out, the plastic deformation was recorded by Grid-Mark method. The result showed that samples have significant deformation, and the latter defomation is far less than the former defomation. Advanced coating technology for machine part is an effective way to improve the ability of resisting low repeated impact.