Formation of galvanic cells between constituent phases is largely responsible for corrosion in Mg-based alloys. We develop a methodology to calculate the electrochemical potentials of intermetallic compounds and alloys using a simple model based on the Born-Haber cycle. Calculated electrochemical potentials are used to predict and control the formation of galvanic cells and minimize corrosion. We demonstrate the applicability of our model by minimizing galvanic corrosion in Mg-3wt%Sr-xZn alloy by tailoring the Zn composition. The methodology proposed in this work is applicable for any general alloy system and will facilitate efficient design of corrosion resistant alloys.

在组成相之间形成原电池是镁基合金腐蚀的主要原因。我们开发了一种方法来使用基于 Born-Haber 循环的简单模型计算金属间化合物和合金的电化学电位。计算出的电化学电位用于预测和控制原电池的形成并最大限度地减少腐蚀。我们通过调整 Zn 成分来最小化 Mg-3wt%Sr-xZn 合金中的电偶腐蚀，从而证明了我们模型的适用性。这项工作中提出的方法适用于任何通用合金系统，并将促进耐腐蚀合金的有效设计。