Recent progress and perspectives in additive manufacturing of magnesium alloys and composites: A review of process-microstructure-property correlations

In recent years, magnesium (Mg) alloys and magnesium matrix composites (MMCs) have made significant progress in the application of advanced equipment, lightweighting and biomedical engineering. Additive manufacturing (AM), with high flexibility and design freedom, is of great significance for the rapid prototyping of high-performance Mg alloy components with complex structures. Due to the layer-by-layer deposition characteristics of additive manufactured Mg alloys and MMCs, the components exhibit distinct microstructures and properties compared to those manufactured via traditional technologies. AM technology for Mg alloys and MMCs still faces challenges in practical applications, including raw materials, processing conditions, post-processing, and selection of process parameters. This paper presents an overview of recent progress in Mg alloys and MMCs fabricated using various AM technologies, including wire-arc directed energy deposition (WA-DED), laser powder bed fusion (LPBF) and solid-state additive manufacturing (SSAM). The relationships between process parameters, forming quality, microstructure and properties are systematically discussed. In particular, the influence of manufacturing processes and material composition on corrosion behavior and biocompatibility is investigated. Additionally, mechanisms and applications of field-assisted additive manufacturing and post-treatment in defect suppression, microstructure evolution, and performance improvement in Mg alloys and MMCs are summarized. Finally, the potential applications of AM Mg alloys and MMCs are prospected, and future development trends are proposed.