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The porous SiC ceramic foam/Zr-based metallic glass interpenetrating phase composites were prepared by water quenching after pressure infiltration. Effects of pore density on microstructure and mechanical properties of interpenetrating phase composites are reported. Microstructural investigations show that the metallic glass is completely infiltrated into the open pores of the SiC ceramic foams and a typical interconnected amorphous phase is formed. A ~10 µm thick diffusion layer in which the reactant ZrC is generated can be found between the ceramic phase and the glassy phase. The average size of the metallic glass phase decreases with increasing the pore density. The results of the quasi-static compression tests indicate that the compressive strength of the composites increases with the pore density of the SiC foams due to the formation of more high-quality interfaces. The brittle fracture of the composites is mainly attributed to the premature destruction of the SiC foams. The results of friction tests imply that compared with monolithic Zr-based BMG samples, the reinforcement of SiC retards the adhesive wear and plastic deformation of Zr-based BMG, and reduces the friction coefficient of the composites.

The interface structure of {2 2 ‾ 01} α2-Ti3Al deformation twins formed during tensile deformation of polysynthetically twinned (PST) TiAl single crystals at 900 °C has been studied systematically by aberration-corrected scanning transmission electron microscopy. Numerous superlattice intrinsic stacking faults (SISFs) are formed on the (0001) basal plane of α2 twins, thereby resulting in the formation of steps on the twin boundaries. The height of steps equals to the spacing of the (2 2 ‾ 01) twinning plane. The basal-plane SISFs formed in α2 twins can't be attributed to the glide of Shockley superpartial dislocations. Lattice correspondence analyses based on classical twinning theory reveal that complex atomic shuffle and interchange shuffling are responsible for the formation of twinning and basal-plane SISFs in α2 twins. In addition, basal-plane antiphase boundaries (APB) are formed at the vicinity of α2 twin tips to relieve the stress concentration imposed by misfit dislocations.