Experimental analysis on fusion ratio and composition uniformity of laser hot wire welds

Ductile cast iron is welded with filling stainless steel hot wire in this article, then fusion ratio and distribution of elements are studied.The fusion ratio is as low as 38%-55%.The composition of filler wire distributes in welds uniformly.Nonuniform degrees of element Cr and Ni are 0.5% and 6%.Compared with laser hot wire welding, the fusion ratio of laser-MIG hybrid welds is 69%-77%, and the nonuniform degrees of element Cr and Ni are not less than 62% and 51%.The low electric energy input and its high utilization ratio for heating filler wire contribute to lower fusion ratio in laser hot wire welding compared to laser-MIG hybrid welding.The uniform distribution of filler wire in laser hot wire welds results from the low fusion ratio and solid filler wire transfer.