关键词: Ti基非晶合金, 非晶合金复合材料, SiC陶瓷骨架, 准静态压缩, 抗压强度

Abstract: The deformation and fracture mechanism of Ti-based amorphous alloy/SiC ceramic matrix composites were studied through quasi-static compression test, which provides the basis for the composition design and engineering application of this kind of materials. The specimens were composed of Ti-based amorphous alloy and SiC ceramic skeleton with different porosities. Under different strain rates, the mechanical properties of the specimens were tested under axial quasi-static compression at room temperature, and the microstructure and cross-section characteristics of the specimens were observed. The results show that the quasi-static compressive strength of the composites with 85% volume fraction of SiC reaches 2 343 MPa, and the compressive strength increases with the increase of SiC content. In the range of the strain rate under quasi-static loading, the strength of the composites and each phase is insensitive to the strain rate, and the fracture characteristics are typical brittle fracture. The crack propagation is mainly at the interface of SiC phase and two phases, and the relative crack propagation of Ti-based amorphous is hindered. The constraint of SiC relative to Ti-based amorphous phase induces the formation of multiple shear bands in Ti-based amorphous phase and improves the deformation capacity of composites. However, the constraint of Ti-based amorphous relative to SiC phase leads to serious fragmentation of SiC phase and enhances the bearing capacity of composites.

Key words: Ti-based amorphous alloys, amorphous alloy composites, SiC ceramic framework, quasi-static compression, compressive strength