Influence of processing parameters on deposition characteristics of Inconel 625 superalloy fabricated by laser solid forming

A series of single track clads of Inconel 625 alloy were fabricated by laser solid forming. To achieve the high dimensional accuracy and excellent mechanical properties, the effect of processing parameters on the geometry, the formation of Laves phase and the residual stress was investigated. The results show that laser power and scanning speed had a dramatical influence on the width and height of single-track clads. According to the columnar to equiaxed transition curve of Inconel 625, the grain morphology can be predicted during the LSF process. With the increasing laser power and the decreasing scanning speed, the segregation degree of Si, Nb, Mo, the volume fraction and size of Laves phase increased. Vickers indentation was used to demonstrate that optimizing processing parameter can achieve the minimum residual tensile stress.