Advanced short-fiber eco-sustainable reinforced composites with metal and ceramic matrices: Current trends, challenges, and future directions

Advanced short-fiber composites reinforced with metal, ceramic, or metal-ceramic hybrid matrices are becoming multifunctional materials for lightweight, thermally stable, and sustainable structural applications. This paper provides a thorough review of the current developments in the properties of composites reinforced with short fibers. The focus of the current study is on composites having metallic matrix, ceramic matrix, and dual-matrix structures. Various topics are discussed in detail like the interactions of fiber and matrix, transfer of load, wettability, nature of bonding in the composites and growth of microstructures. Various important processing techniques like stir casting, powder metallurgy, spark plasma sintering, geo-polymerization, and additive manufacturing are also discussed. Various challenges that are normally encountered during composites processes like fiber agglomeration, porosity, degradation of interface, existence of residual thermal stress, and limitation on scalability are also discussed. Various recent developments in multi-scale characterization, multiphysics modeling, lifecycle assessment, and AI/ML-assisted material designing are also summarized in the current study. The current study concludes that the combination of the metal's ductility and thermal stability of ceramics will ensure the utilization of the above-mentioned dual-matrix composites in various applications like aerospace, automotive, and refractory structural applications. Finally, future development directions are proposed, including the use of waste-derived reinforcing materials, multi-material additive manufacturing, spark plasma sintering, and ICME-based design frameworks to accelerate the development of next-generation short-fiber-reinforced sustainable composite materials.