Microstructure characterization and fracture behaviors of Silicon carbide/metallic glass composites with interpenetrating architecture

Abstract

Silicon carbide/metallic glass interpenetrating phase composites (SiC/MG IPCs) have attracted great attention due to their superior performances. However, the effect of the interface on the mechanical properties remains unclear. In this paper, three SiC three-dimension network scaffolds (SiC 3D-NSs) with different volume fractions and surface areas were firstly prepared by selecting SiC particles of different sizes, and the corresponding SiC/MG IPCs were further prepared using vacuum pressure infiltration and water quenching. The microstructure and mechanical properties of the scaffolds and related IPCs were studied. The SiC and MG phases are continuous, mutually interpenetrated in 3D space. The strength of the scaffolds and related IPCs are positively correlated with the SiC volume fraction. It is found that partial crystallization of MG occurred at the interface due to the increase in interface thermal resistance and heterogeneous nucleation. During compression or bending, such the interfacial structure can retard the main crack propagation by initiating a large number of secondary cracks. It contributes to an apparent increase in the crack propagation path, significantly improving the fracture toughness of IPCs. This result shows that interface engineering in IPCs is of great significance for improving their toughness.