The surface treatment of the metal substrate has a significant effect on the adhesion between the metal sheet and fiber/epoxy prepreg. The effect of the surface treatment methods, including sandpaper abrasion, phosphating treatment, anodizing and plasma electrolytic oxidation (PEO), on the surface morphology, surface energy and shear strength of WE43 magnesium alloy was analyzed in this study. The surface roughness is noted to have a significant effect on the wettability of WE43 magnesium alloy. The roughness and surface energy of the phosphated WE43 magnesium alloy are observed to be the largest among the four surface treatment methods, and the corresponding values are 4.17 and 70.8 mJ/m², respectively. The lap-shear tensile tests reveal that WE43 magnesium alloy treated by the PEO process possesses the highest shear strength. Overall, the shear strength of the samples after phosphating treatment, anodizing and PEO treatment is noted to improve by 46%, 61% and 116% respectively, as compared with the sample treated by sandpaper abrasion. The observed superior shear properties after PEO treatment have been attributed to the cylindrical pores conducive to the infiltration of the epoxy resin during the curing process, thus, enhancing the adhesion between WE43 magnesium alloy sheet and epoxy resin. Additionally, the shear fracture mechanism was also analyzed in detail.

金属基材的表面处理对金属片与纤维/环氧树脂预浸料之间的附着力有显着影响。分析了砂纸磨蚀、磷化处理、阳极氧化和等离子电解氧化（PEO）等表面处理方法对WE43镁合金表面形貌、表面能和剪切强度的影响。注意到表面粗糙度对 WE43 镁合金的润湿性有显着影响。经观察，磷化后的WE43镁合金的粗糙度和表面能在四种表面处理方法中最大，对应值分别为4.17和70.8 mJ/m ²， 分别。搭接剪切拉伸试验表明，经 PEO 工艺处理的 WE43 镁合金具有最高的剪切强度。总体而言，磷化处理、阳极氧化和PEO处理后的样品的剪切强度与砂纸磨损处理的样品相比分别提高了46%、61%和116%。PEO处理后观察到的优异剪切性能归因于在固化过程中有利于环氧树脂渗透的圆柱形孔，从而增强了WE43镁合金板与环氧树脂之间的粘附力。此外，还详细分析了剪切断裂机理。