Preparation, material modification and cryogenic mechanical properties of fiber-reinforced polymer (FRP) composites

Fiber-reinforced polymer (FRP) composites are extensively employed in advanced engineering applications including aerospace, marine systems, and civil infrastructure owing to their high specific strength and modulus, exceptional corrosion resistance, and tailorable properties. However, matrix resin embrittlement and fiber-matrix interface degradation under cryogenic conditions induce progressive mechanical deterioration, fundamentally compromising operational viability in extreme environments. Through critical analysis of decade-spanning research literature, this review examines advancements in FRP composite manufacturing and cryogenic performance across four key domains: material fabrication, modification methodologies, interfacial micro characterization, and macroscopic mechanical responses. First, standard FRP manufacturing processes are elucidated. Next, three principal modification approaches are systematically categorized: matrix modification, fiber treatment, and hybrid reinforcement. Subsequently, advanced characterization techniques including scanning electron microscopy (SEM) and atomic force microscopy (AFM) reveal cryogenic-induced failure mechanisms encompassing matrix embrittlement, interfacial debonding, and crack propagation. Finally, the review synthesizes findings on cryogenic mechanical behaviors including tensile, compressive, flexural, and shear properties. Future research priorities are identified, particularly nano reinforcement development and fiber-matrix interface optimization, to establish theoretical frameworks and technical protocols for FRP applications in extreme environments.