Topography of the Grain Boundary on Stainless Steel Surfaces Varied by Nanosecond Laser Irradiation

摘要

We designed a laser local heating system for controlling microstructures including the grain boundary observation system. Two kinds of laser, the CW laser and a short pulse laser, were employed in this system. The CW laser and the short pulse laser were a fiber laser and a nanosecond laser, respectively. The sample was a stainless steel (Type 304) plate. Grain boundaries on the stainless steel plate surface were examined by optical image measurement as the topography of the grain boundaries was changed after the nanosecond laser irradiation. Then, the grain could be selected for local heating with the fiber laser.