Diffusion behavior of chromium in the laser remolten layer of electroplated chromium coating on Inconel 690 alloy tube

The laser remolten layer was made on the Inconel 690 alloy tubes by using electroplated chromium and laser irradiation.Through the scanning electron microscope(SEM) and energy dispersive X-Ray spectroscopy(EDX),the microstructure of the electroplated coating and the laser remolten layer was investigated,as well as the diffusion behavior of chromium in the layer.The results show that in the thin laser remolten layer,from the outer surface to the interior of the tube,the chromium concentration gradient is larger,and the concentration reduces gradually.With the laser remolten layer depth increases,the diffusion depth of chromium increases and element distribution trends uniform.