Research on surface finish of thin-wall parts by laser with coaxial inside-beam powder feeding

Abstract

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.