Influences of crystal orientation of substrate on microstructure of multi-layer laser cladding

The influence of the crystal orientation of the substrate on microstructure is investigated by multi-layer laser cladding with the powder of nickel-base superalloy. With properly organized processing conditions, if the crystal orientation of the surface of the substrate is parallel to the preferred crystal orientation, cladding with the identical crystal orientation to the substrate can be obtained. The cladding layers exhibits fine and regular columnar dendrite except that a thin layer with altered orientation appears at the surface of the external layer. When the experiment was performed on other crystal faces of the substrate, there appears fine and random oriented dendrite.