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利用分离式霍普金森压杆(SHPB)装置对三维连通网状SiC陶瓷/Zr基非晶复合材料进行不同应变率下的动态压缩实验,并与准静态压缩实验结果比较.利用X射线衍射仪和扫描电子显微镜研究了复合材料的相组成和断口形貌.结果表明:在压缩条件下三维连通网状SiC陶瓷/Zr基非晶复合材料的断裂发生在弹性变形阶段,断裂前几乎观察不到塑性变形;复合材料的准静态压缩强度达到了1 270 MPa,高于在动态压缩中的断裂强度1 100 MPa.试样发生纵向劈裂和剪切断裂,准静态下试样形成的破片数量较多,动态加载条件下试样破碎成数量较少的较大块体.三维连通网状SiC陶瓷断口形貌为层片状、台阶式的解理断裂,非晶合金发生粘性流动,在变形过程中形成脉状花样,在高应变率加载条件下,非晶热软化严重,断口形貌复杂多样.
The dynamic compressive experiments at different strain rates of three-dimensional connected reticular SiC ceramic / Zr-based amorphous composites were carried out by using a split Hopkinson pressure bar (SHPB) device and compared with the results of quasi-static compression experiments. The X-ray diffraction And the phase morphology of the composites were investigated by scanning electron microscopy.The results show that the fractures of the three-dimensional interconnected reticular SiC / Zr-based amorphous composites occur at the stage of elastic deformation under compression and are hardly observable before fracture Plastic deformation; the quasi-static compressive strength of the composite reaches 1 270 MPa, which is higher than the breaking strength of 1 100 MPa in dynamic compression. The specimens are longitudinally cleaved and sheared and fractured, and the quasi-static specimens form more fragments And the sample is broken into a large number of blocks with a small number under dynamic loading conditions.The morphology of the fracture surface of the three-dimensionally connected reticular SiC ceramics is lamellar and step-wise cleavage and fracture, and the viscous flow of amorphous alloy occurs during the deformation process In the formation of vein pattern, at high strain rate loading conditions, the amorphous heat softening severe fracture complex and diverse.