Improved Formability and Corrosion Resistance of Pure Magnesium by Parts-Per-Million-Level Addition of Copper and Calcium

Poor cold formability, poor corrosion resistance, and high cost of alloying elements are longstanding barriers to the widespread use of magnesium (Mg) and its alloys. In this study, we demonstrated that both the room temperature (RT) stretch formability and corrosion resistance of commercially used pure Mg could be significantly improved by adding trace amounts of copper (Cu) and calcium (Ca). Owing to the addition of trace amounts of the alloying elements, the resultant alloy also showed excellent thermal conductivity, which is almost two times higher than that of the most commonly used Mg alloy (AZ31) and even higher than that of a commercial Al alloy (A5052). These findings are expected to stimulate the development of high-performance Mg alloys that can be used in portable electronic devices, automobile electronics, and household appliances.