Microstructure evolution and enhanced mechanical properties of CF/Mg composites with optimized fiber/matrix interfacial adhesion

In this study, the optimal carbon fiber/matrix (CF/matrix) interfacial adhesion was explored by tailoring sintering pressures, aiming to enhance the ultimate tensile strength (UTS) of CF/Mg composites. With increasing the pressure, the interfacial shear strength (IFSS) gradually increased from 28.8 MPa to 43.6 MPa. Remarkably enhanced UTS (152 MPa) of the composite was achieved, which was 120.3 % higher than that of the matrix, through optimizing the IFSS to 39.7 MPa. Correspondingly, the main failure mechanism was fiber pulling-out and direct fiber-cutting. Whereas, excessive IFSS (43.6 MPa) deceased the UTS of the composite, with the dominant failure mechanism of direct fiber-cutting. [Display omitted] •The CF/matrix interfacial adhesion was effectively optimized for enhanced mechanical properties of CF/Mg composites.•With an optimal interfacial adhesion, remarkable enhanced UTS (152 MPa) was achieved, which was 120.3 % higher than matrix.•An optimal interfacial adhesion contributed to effective load transfer and more harmful energy absorption at the interface.