基于正态分布的喷丸表面覆盖均匀程度与强化效率研究

目的提高喷丸表面覆盖率分布的均匀程度和强化效率。方法采用图像处理技术分析了单道次喷丸表面覆盖率在喷丸宽度方向上的分布特征,采用正态分布函数对多道次喷丸表面覆盖率分布的均匀程度以及喷丸强化效率进行了研究。结果单道次喷丸中,表面覆盖率在喷丸宽度方向上的分布近似呈正态分布。多道次喷丸中,相邻喷丸道次间距对表面覆盖率影响较大,道次间距越小,表面覆盖率越均匀,两者近似呈线性变化关系。当表面覆盖率均匀程度变化范围在0.91~0.99时,道次间距越小,喷丸强化效率越高。而且,喷丸强化效率受构件长度方向尺寸的影响,尺寸越小,不同喷丸道次间距对应的喷丸强化效率越接近。结论合理选择相邻喷丸道次间距,可在保证喷丸强化效率的基础上有效地提高表面覆盖均匀程度。

Uniformity of Surface Coverage and Strengthening Efficiency in Shot Peening Process Based on Normal Distribution

The work aims to improve the uniformity of surface coverage and the strengthening efficiency of shot peening (SESP). The distribution characteristics of surface coverage in width direction of shot peening was analyzed in single path shot peening (SPSP) by image processing techniques and the distribution uniformity of surface coverage and SESP were investigated in multi paths shot peening (MPSP) by normal distribution function. In SPSP, surface coverage in width direction of shot peening approximated normal distribution. In MPSP, the surface coverage was significantly affected by the adjacent path spacing. The smaller the path spacing was, the more uniform the surface coverage distribution was. There was an approximate linear relationship between the two. SESP increased as the path spacing decreased when the uniformity of surface coverage changed from 0.91 ~ 0.99. Moreover, SESP was also influenced by the length of the peened component and the corresponding SESP for different path spacing got closer as the length reduced. The uniformity of surface coverage can be improved on the basis of ensuring the SESP by selecting the adjacent path spacing reasonably.