Recent developments in rare-earth free wrought magnesium alloys having high strength: A review

To further expand industrial application of Magnesium alloys, developments of the low-cost, Rare-Earth free Magnesium alloys with high strength were strongly desired. In this review, recent researches on the Rare-Earth free Magnesium alloys will be critically reviewed from the viewpoint of the novel alloying designs, e.g. Magnesium–Zinc, Magnesium–Tin and Magnesium–Calcium systems, and advanced processing technologies to summarize the experimental progresses in pursuing high strength. Considering the large strength gap between the current Rare-Earth free Magnesium alloys and state-of-the-art Magnesium-Rare-Earth alloy or high strength Aluminum alloy, the new strengthening mechanism, such as the solute clustering which was recently observed in Magnesium-Rare-Earth alloys and the other Rare-Earth-free Magnesium systems, was suggested. Accordingly, the new alloy design and processing routes, and also the future research directions for Rare-Earth-free Magnesium alloys would be proposed. •Recent researches on Rare-Earth free magnesium alloys having high strength were critically reviewed.•Both the promise alloying systems and advanced processing technologies were included.•New strengthening mechanism of solute clustering was suggested.•The future research directions for Rare-Earth-free magnesium alloys were proposed.