Research progress on preparation, interface control and properties of Si3N4 particle reinforced aluminum matrix composites

Among numerous metal matrix composites, aluminum matrix composites often have theoffer advantages of lightersuch as low density, higher specific strength, specific and modulus, good thermal conductivity, higher corrosion resistance and wear resistance, . and have beenThey are widely used in aerospace, transportation, electronic devices, precision instruments,and thermal management and other fields. It is well known that the final properties of composites are affected by the type, content and size of reinforcements. Among the reinforcements of aluminum matrix composites, Silicon nitride (Si3N4) ceramics, as a reinforcement, have exhibit high hardness and,high elastic modulus, certain thermal conductivity, a relatively low thermal expansion coefficient (CTE),thermal stability, chemical stability and other excellent properties, especially lower thermal expansion coefficient and higher toughness compared with other ceramics. Si3N4/Al composites prepared by using Si3N4 as reinforcement can meet emands for matched CTE and tailored mechanical properties in structural componentsthe requirements of thermal expansion coefficient and plasticization matching with bearing steel by reducing the content of reinforcement while ensuring the required mechanical properties of the composites, so as to meet the performance requirements of the structural components. In this paper, the research background, main preparation process and characteristics, interface structure, reaction mechanism and mechanical properties of Si3N4/Al composites are systematically reviewed, and the future challenges and directions are pointed out. This paper provides a systematic review of the research progress on Si₃N₄/Al composites, encompassing mainstream preparation techniques, interface control, properties, and joining methods. Key quantitative findings highlighted include: stir-cast and hot-extruded composites achieving a 31% increase in hardness, 11% higher yield strength, and 66% greater elongation; pressure-infiltrated composites with high Si₃N₄ volume fractions attaining a thermal conductivity of 252 W/(m·K) alongside a low CTE of 7–10×10⁻⁶/K; and spark plasma sintered composites reaching near-full density (>99%) with refined microstructures. The critical influence of interfacial reactions, particularly the role of Mg in forming beneficial phases like MgAl₂O₄, is emphasized. Furthermore, advanced joining techniques such as ultrasonic brazing are discussed for their potential to enable flux-free, reliable integration of components. Future challenges and directions are identified: (1) achieving scalable, low-cost manufacturing with uniform microstructure; (2) atomic-scale understanding and precise control of interfacial reactions; (3) breaking the strength-toughness trade-off through multi-scale architectural design; (4) standardizing reliable joining processes; and (5) expanding applications in aerospace and advanced electronics. This review aims to furnish a comprehensive foundation for the design and application of high-performance Si₃N₄/Al composites.