Objective The purpose of this study is to investigate the influence of cryogenic treatment and age-hardening heat treatment on the corrosion behavior of a dental casting Ag-Pd alloy. Methods A low gold content dental casting alloy composed of Ag-Pd-Cu-Au was prepared for this study. Corrosion test was performed according to ISO 10271:2001 dental metalliecorrosion test methods. Experimental specimens were casted according to a standard dental lost-wax casting procedure, treated with solution by heating the specimens to 900 ℃, and immediately quenched in ice water. The specimens were then divided into four groups and subjected to heat treatment, cryogenic treatment, and heat treatment combined with cryogenic treatment. The specimens after the solution treatment were taken as control. The metallographic structures of the specimens were observed. The electrochemical parameters and the quantity of non-precious metallic ions released were evaluated via electrochemical and static immersion tests. Results Metallographic observation revealed that all the treatments resulted in a change in the microstructure of the alloy. The treatments were effective in improving the electrochemical parameters, such as an increase in Eocp and Ecorr and a decrease in Icorr (P<0.05). The amount of non-noble metal ions released showed no difference compared with the control group (P>0.05). Conclusion After different treatments, the antierosion properties of the alloy satisfied the ISO requirements. Age-hardening heat treatment and cryogenic treatment improved the corrosion resistance of the alloy.%目的：研究不同处理对牙科用银钯铸造合金腐蚀行为的影响。方法熔炼银钯铸造合金，参照ISO10271：2001牙科金属材料抗腐蚀实验标准，按照标准牙科失蜡法铸造程序制作测试样本，经固溶软化处理后，分别进行相应的热处理、深冷处理、热处理并深冷处理，以固溶软化处理组作为对照组。采用金相显微镜观察分析，并行电化学实验、静态浸泡实验测试合金的电化学参数及非贵金属离子析出值。结果各实验组的金相结构发生了变化，电化学参数的开路电位Eocp、腐蚀电位Ecorr及腐蚀电流密度Icorr与对照组的差异有统计学意义（P<0.05），但各实验组与对照组银、钯、铜离子析出量的差异无统计学意义（P>0.05）。结论各组的抗腐蚀性能指标均能满足ISO标准的要求，适当的热处理、深冷处理、热处理并深冷处理能改善实验合金的抗腐蚀性能。
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