【摘要】 镁合金由于耐蚀性较差，限制了其大规模应用。Ce是一种最常见的稀土元素，具有储量大、密度低和经济效益好等特点，对于镁合金耐蚀性的提升有显著作用。以AT61合金为基础，通过添加1%（质量分数）Ce研究其对合金铸态组织和腐蚀行为的影响。根据XRD和SEM/EDS结果分析可知，添加1%Ce后AT61合金中Mg₁₇Al₁₂相由沿晶界连续分布转变为棒状或块状的不连续分布，且数量显著下降。AT61-Ce合金中除Mg₁₇Al₁₂和Mg₂Sn相外，还存在新的针状Al₄Ce相。根据析氢实验和电化学性能测试，添加1%Ce后AT61合金的耐腐蚀性能显著提高。AT61-Ce合金的自腐蚀电流密度和极化电阻分别为14.223μA/cm²和2 279.951Ω/cm²。AT61-Ce合金良好的耐蚀性能归因于Mg₁₇Al₁₂相体积分数下降，微电偶腐蚀减弱及Al4Ce相沿晶界连续分布阻碍腐蚀扩展。更多还原

【Abstract】 Large-scale applications of magnesium alloys are limited because of their poor corrosion resistance.Ce is the most common rare earth element and has the advantages of large reserves,low density,and good economic benefits,playing a significant role in improving the corrosion resistance of magnesium alloys.The effect of adding 1 wt.%Ce to the as-cast microstructure and corrosion behavior of the AT61 alloy was investigated.According to the XRD and SEM/EDS results,the Mg₁₇Al₁₂phase in the AT61 alloy transforms from a continuous distribution along the grain boundaries to a discontinuous distribution with a rod-like or block shape after the addition of 1 wt.%Ce,and the quantity significantly decreases.In addition to the Mg₁₇Al₁₂and Mg₂Sn phases,new needle-like Al₄Ce phases are present in the AT61-Ce alloy According to hydrogen evolution tests and electrochemical performance tests,the corrosion resistance of the AT61 alloy is significantly improved.The self-corrosion current density and polarization resistance of the AT61-Ce alloy are14.223μA/cm² and 2 279.951Ω/cm²,respectively.The excellent corrosion resistance of the AT61-Ce alloy is attributed to the decrease in the volume fraction of the Mg₁₇Al₁₂phase,the weakening of galvanic corrosion,and the continuous distribution of the Al₄Ce phase along the grain boundaries hindering corrosion propagation.更多还原