Environment-COnscious magnesium (ECO-Mg): A review

Abstract

The significance of Mg (alloy) extends to both the mechanical engineering and medical sectors. However, Mg is known for its high reactivity, posing significant challenges to its widespread utilization in large-scale lightweight applications. Research has shown that adding small amounts of reactive elements, such as Ca, can substantially improve the high-temperature oxidation resistance of numerous Mg alloys. This can diminish the reliance on greenhouse gases with high global warming potential, typically used as protective gases during processing. In a similar vein, the patented Environment-COnscious Mg technology offers distinct advantages by utilizing the cost-effective and more stable oxide form of the desired alloying element, notably alkaline earth metals like Ca, instead of their elemental forms, in the alloying of Mg. This development holds considerable importance in mitigating the carbon footprint throughout manufacturing. While the patents for Environment-COnscious production outline a method employing various versatile oxides, practical application has primarily relied on adding calcium oxide, as indicated by the literature. Therefore, this review brings to light the state of the art concerning the interaction between calcium oxide and molten Mg (alloy), and its influence on the technical properties, potential challenges, and areas requiring further investigation in this field. Until now, this issue has not been discussed from a critical and holistic approach.