Study on Polishing DF2 (AISI O1) Steel by Nd: YAG Laser

Pulse Nd: YAG laser was used to polish DF2 cold work steel. Influence of irradiation parameters on the 3D surface topography was studied by 3D profilometer, scanning electron microscopy (SEM), and atomic force microscope (AFM). Results among the tests showed when DF2 specimens were irradiated with parameters of (i) laser input energy P=1 J, (ii) pulse feedrate=300 mm/min, (iii) pulse duration PD=3 ms, and (iv) pulse frequency f=20~25 Hz, laser polishing of DF2 cold work steel seemed to be successful. Also, effect of laser polished parameters on the laser polishing temperature was described and the analysis of temperature field of laser polishing was herewith proposed. It demonstrated that for a given laser, influence of laser pulse feedrate was more prominent than that of other parameters on the topography of a laser polished surface. Moreover, the mechanism of laser polishing relied on the heat-input interaction with the base metal. When Hinput=Hthreshold, the mechanism of laser polishing principally relied on the metal melting; When Hinput>Hthreshold, the mechanism of laser polishing was a combination of metal evaporation and melting; and when Hinput>>Hthreshold, the mechanism of laser polishing mainly relied on the metal evaporation.