Although Mg alloy attracts great attention for engineering applications because of high specific strength and low density, low corrosion resistance limits its extensive use. In this study, Mg–Al–Zn–Mn alloy was treated via a laser cladding process to generate a dense and compact laser cladding layer with solid metallurgical bonding on the substrate for improving corrosion resistance, effectively hindering the corrosion pervasion into Mg alloy. The corrosion current density declined from 103 μA/cm² for Mg alloy to 13 μA/cm² for the laser cladding layer in NaCl aqueous solution. Moreover, the laser cladding layer was slightly corroded in comparison with Mg alloy in NaCl aqueous solution. Besides, the microhardness of the cladding layer reached a mean value of 170.5 HV, 3.1 times of Mg alloy (56.8 HV) due to the in situ formation of hardening intermetallic phases. Wear resistance of laser cladding layer was also obviously improved. These results demonstrated that the laser cladding layer obviously enhanced anticorrosion property of Mg alloy for engineering applications.

中文翻译：

---

具有固态冶金结合的致密致密激光熔覆层可显着提高镁合金的耐蚀性，可用于工程应用

尽管镁合金由于高比强度和低密度而在工程应用中引起了极大的关注，但是低的耐腐蚀性限制了其的广泛使用。在这项研究中，Mg-Al-Zn-Mn合金通过激光熔覆工艺进行处理，以在基底上产生紧密致密的激光熔覆层，并具有固体冶金结合，从而提高了耐腐蚀性，有效地阻止了腐蚀扩散到Mg合金中。腐蚀电流密度从103μA/厘米下降²为Mg合金13μA/厘米²用于NaCl水溶液中的激光熔覆层。此外，与NaCl水溶液中的Mg合金相比，激光熔覆层被轻微腐蚀。此外，由于原位形成的硬化金属间相，包覆层的显微硬度达到平均值170.5 HV，是Mg合金（56.8 HV）的3.1倍。激光熔覆层的耐磨性也明显提高。这些结果表明，激光熔覆层明显增强了镁合金在工程应用中的防腐性能。