Surface quality is an important performance indicator of laser metal deposition. Based on annular laser beam internal powder feeding technology, the effect of higher energy of the outer side of the annular beam on the surface roughness and waviness of thin-wall parts is studied in this paper. The influences of laser power, scanning speed, and powder feeding rate on the surface finish of thin-wall parts are investigated. The results show that the laser power has a significant effect on surface finish. With the increase in laser power, the roughness decreases and the waviness increases first and then decreases. High laser power can improve surface finish. As the scanning speed increases, the roughness decreases first and then increases, and the waviness decreases. The scanning speed has a significant influence on surface waviness. Increasing the powder feeding rate is not beneficial to surface quality because the value of the roughness and the surface waviness will add with its rising.

中文翻译：

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同轴束内送粉激光薄壁件表面光洁度研究

表面质量是激光金属沉积的重要性能指标。本文基于环形激光束内部送粉技术，研究了环形光束外侧较高能量对薄壁零件表面粗糙度和波纹度的影响。研究了激光功率、扫描速度和送粉速度对薄壁零件表面光洁度的影响。结果表明，激光功率对表面光洁度有显着影响。随着激光功率的增加，粗糙度减小，波纹度先增大后减小。高激光功率可以改善表面光洁度。随着扫描速度的增加，粗糙度先减小后增大，波纹度减小。扫描速度对表面波纹度有显着影响。