Microvoid coalescence-mediated toughening in B4C@B2O3/Al composites via interfacial nanoamorphous layer modification

A nanoamorphous B 2 O 3 layer was successfully introduced at the interface of B 4 C/Al composites, leading to a significant enhancement in ductility without sacrificing strength. This improvement in ductility is attributed to the microvoid coalescence-like fracture mechanism observed during in-situ TEM tensile testing. The microvoids nucleate from point defects within the interfacial amorphous layer. As a result, a zig-zag fracture path forms, effectively dissipating energy and contributing to the enhanced ductility. These findings offer critical insights into the design of B 4 C/Al composites with an optimal balance of strength and ductility.