现有激光熔覆技术大多是基于水平基面上开展的，这种方式极大地限制了激光熔覆技术的广泛应用。基于“光束中空、光内送粉”技术，通过对激光加工机器人系统的程序控制实现了基板0°~150°的倾斜和熔覆头相应姿态的连续变化，研究了基板不同倾斜角度下对熔覆层截面尺寸及组织的影响规律，并对变基面过程中的熔池进行了受力分析。实验结果表明：随基板倾斜角度逐渐增大，粉末聚焦特性变差，进入熔池的粉末量逐渐减少，造成熔覆层高度逐渐降低。熔覆层宽度稳定在光斑左右，变化不明显；偏移量(熔覆层最高点轴线位置偏离激光束轴线位置间的距离)先增大后降低。熔覆层顶部显微组织树枝晶大小先变粗后变细，典型柱状晶生长方向随基板角度变化也发生相应的倾斜。该工艺为在非水平基面上进行激光熔覆、修复及成形提供了参考价值。

Laser cladding technology is based on horizontal reference plane at present, however, this way greatly limits its extensive applications. The substrate inclined angle of 0°~150° and continuously variable postures of coaxial powder nozzle have been achieved by changing the programming to control the laser processing robot adopting the technology of“hollow laser beam and interal powder feeding”. The influence rules of the substrate inclined angle on the section size and microstructure of cladding layers are investigated, and the force of molten pool is analyzed during varging the inclined angles of the substrate. The experimental results show that the powder converging behavior becomes worse with the increase of the substrate inclined angle, because reducing of powder volume into molten pool leads to decreases of the cladding layers′ height. The width of cladding layers do not show significant variations and offset first increase and then decrease. The dendrite size of the cladding layers′ top microstructure first becomes thick and then thin gradually and the growth direction of typical columnar crystal tilts with the substrate inclined angle. The process basis is provided for laser cladding, repairing and forming on variable reference plane by the inside-laser powder feeding way.