Author(s): Zhu Gangxian, Shi Shihong, Fu Geyan, Shi Jianjun, Yang Shi, Meng Weidong Jiang Fubing School of Mechanical and Electric Engineering, Soochow University
Pages: 114-119
Year: 2015 Issue:  3
Journal: Chinese Journal of Lasers
Keyword:  laser technique; laser cladding; robot; variable reference plane; section size; microstructure;
Abstract: 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.