中文摘要：

基于激光光内同轴送粉技术和6轴机器人技术,采用熔覆头空间变姿态的成形方法,通过沿着生长的切线方向连续变角度送粉堆积的方法成形了悬垂薄壁件。建立了倾斜基面熔池受力与位移模型,并通过优化工艺参数抑制熔池的位移和流淌。实验结果表明,倾斜角可从0°逐渐变化至81°,实现了大倾角悬垂结构的无支撑成形。成形件表面平整光滑,完全消除了＂台阶效应＂,表面粗糙度Ra=6.3μm。截面纹理图显示各熔层沿中轴线对称,无明显朝重力方向的偏移。成形件在不同倾角位置的显微组织无明显区别,皆达到晶粒细小,组织致密均匀。

英文摘要：

Combining hollow laser beam inside powder feeding technology and 6-axis robot, a cantilevered thinwalled metal part is deposited layer by layer by means of continuously varying the attitude of laser cladding nozzle along the tangential direction of the thin wall. The modeling of force and displacement of the molten pool on an inclined surface is carried out. The shifting and flow of the molten pool are restrained by optimizing the laser cladding parameters in this model. The experimental results indicate that the forming of the cantilevered part with a changing incline angle from 0° to 81° is achieved without support. And, the surface of this part is flat and smooth,and the＂step effect＂is completely eliminated. The cladding layers are nearly symmetry along the central axis of the part, and the shifts of the layers influenced by gravity are not apparent. The microstructures of the part at different incline angles have no significant differences, and all achieve small grain size and compact texture.