An attempt has been made to improve the surface properties of AZ31B magnesium alloy through solid solution hardening and refinement of microstructures using a CO2 laser as a heat generating source. X-ray diffraction ...An attempt has been made to improve the surface properties of AZ31B magnesium alloy through solid solution hardening and refinement of microstructures using a CO2 laser as a heat generating source. X-ray diffraction （XRD） was used to identify the phases. Microstructure and properties of laser melted layer of AZ31B magnesium alloy were observed or tested by means of optical microscope （OM）, scanning electron microscope （SEM）, micro-hardness equipment and electrochemical corrosion equipment etc. The results show that the microstructure of laser melted layer becomes finer significantly and uniform. Compared with the substrate, the content of β-Mg17 Al12 phase of melted layer decreases comparatively. Microhardness of the laser melted layer is improved to 50 -95 HV0. 05 as compared to 40 -45 HV0.05 of the AZ31B Mg alloy substrate. The results of electrochemical corrosion show that the corrosion resistance of laser surface melted layer has been improved.展开更多
基金The research is supported by the Shanxi Natural Science Foundation （No. 2008011044）.
文摘An attempt has been made to improve the surface properties of AZ31B magnesium alloy through solid solution hardening and refinement of microstructures using a CO2 laser as a heat generating source. X-ray diffraction （XRD） was used to identify the phases. Microstructure and properties of laser melted layer of AZ31B magnesium alloy were observed or tested by means of optical microscope （OM）, scanning electron microscope （SEM）, micro-hardness equipment and electrochemical corrosion equipment etc. The results show that the microstructure of laser melted layer becomes finer significantly and uniform. Compared with the substrate, the content of β-Mg17 Al12 phase of melted layer decreases comparatively. Microhardness of the laser melted layer is improved to 50 -95 HV0. 05 as compared to 40 -45 HV0.05 of the AZ31B Mg alloy substrate. The results of electrochemical corrosion show that the corrosion resistance of laser surface melted layer has been improved.
