Poor plasticity is an intrinsic disadvantage of magnesium (Mg) alloys, which limits their wide application at room temperature. Alloying is an accepted method to tune the plastic deformation mode and improve plasticity. However, the effect of solute atoms on the activation of different dislocations is still unclear and has rarely been systematically investigated in Mg alloys. In this work, the formulations of Peierls-Nabarro stresses (σ_p) for edge and screw dislocations along various slip planes in Mg-X (X = Y, Ca, Nd, Zn, Al and Sn) alloys are firstly derivate, as well as the calculation of the parameter K (energy factor) based on the first-principles calculation. The effects of solute atoms on the σ_p of various types of dislocations are systematically studied. The difference of the σ_p between the Mg-X alloy and pure Mg, i.e., Δσ_p, is determined, which is strongly influenced by the solute atoms. The negative Δσ_p reflects the promotion of dislocation activation. The relationship between the Δσ_p of different non-basal dislocations and elongation in eight Mg-X alloys is explored. The simultaneous improvement of the activation of the prismatic 〈a〉 and the pyramidal 〈c + a〉 dislocations is discovered, which can be achieved by specific alloying elements. Cooperative activation of the prismatic 〈a〉 and the pyramidal 〈c + a〉 dislocations owing to the reduced Δσ_p is shown to closely correlate with the significant increased plasticity of the Mg alloys. These findings advance a novel perspective on alloy design strategies for Mg alloys with improved plasticity.

Mg matrix composites (MgMCs) with enhanced mechanical and functional properties, as well as improved elastic modulus, have aroused rising attention from the aerospace, new energy vehicles, and consumer electronics industries. The suitability of the fabrication process is crucial for achieving uniform dispersion of various reinforcing materials within the Mg alloy matrix and for forming strong interfacial bonding. This ensures that the produced MgMCs meet the requirements for fabricating various components with different demands for size and properties. This paper comprehensively reviews the present fabrication methods for MgMCs in four categories: stir casting, external addition methods, in-situ synthesis methods and novel fabrication methods. It comprehensively focuses on the fabrication principles, process characteristics and key parameters optimization of each technology. Through in-depth analysis, their advantages, limitations and applications are evaluated. Meanwhile, the latest research achievements in microstructure control and mechanical performance optimization are explored. Eventually, the development directions of the fabrication methods for MgMCs in the future are also discussed.

Magnesium matrix composites have garnered significant attention in recent years owing to their exceptional lightweight properties and notable potential in various engineering applications. The interface generally acts as a “bridge” between the matrix and reinforcement, playing crucial roles in critical processes such as load transfer, failure behavior, and carrier transport. A deep understanding of the interfacial structures, properties, and effects holds paramount significance in the study of composites. This paper presents a comprehensive review of prior researches related to the interface of Mg matrix composites. Firstly, the different interfacial structures and interaction mechanisms encompassing mechanical, physical, and chemical bonding are introduced. Subsequently, the interfacial mechanical properties and their influence on the overall properties are discussed. Finally, the paper addresses diverse interface modification methods including matrix alloying and reinforcement surface treatment.