Abstract SiCf/C/Mo/Ti2AlNb composites were prepared by foil-fiber-foil (FFF) method and are used as model system to study the effect of solution-ageing treatments on the interface and mechanical properties of SiC fiber-reinforced TiAl-matrix composites. By contrast, SiCf/C/Ti2AlNb composites were prepared and heat treated under the same process parameters. The interfacial microstructures of the as-prepared and heat treated composites were investigated by means of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Tensile strength tests of the composites were carried out at room temperature. So the effect of C/Mo duplex coated SiC fibers on the microstructure and tensile behavior of the composites was studied. The results reveal that the interfacial thermal stability and integrity of the SiCf/C/Mo/Ti2AlNb composites are much better than those of the SiCf/C/Ti2AlNb composites, as the C/Mo duplex coating can reduce the formation of brittle α2-phase and relieve the interfacial thermal residual stresses in SiCf/Ti2AlNb composites compared with C single coating. After the 1080 °C/1 h/850 °C/20 h heat treatment, the matrix of the SiCf/C/Mo/Ti2AlNb composite transformed into mainly B2+O homogenous mixture and a small amount of α2 phase, and the tensile strength of the composite was tested, which shows that the tensile properties of the composite was maintained after the solution-ageing treatment.

中文翻译：

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固溶时效处理对SiC f /C/Mo/Ti 2 AlNb复合材料组织和拉伸性能的影响

摘要 采用箔-纤维-箔（FFF）法制备 SiCf/C/Mo/Ti2AlNb 复合材料，并作为模型系统研究固溶时效处理对 SiC 纤维增强 TiAl 基体界面和力学性能的影响。复合材料。相比之下，SiCf/C/Ti2AlNb 复合材料在相同的工艺参数下制备和热处理。通过扫描电子显微镜 (SEM) 和能量色散 X 射线光谱 (EDS) 研究了制备和热处理复合材料的界面微观结构。复合材料的拉伸强度测试在室温下进行。因此，研究了C/Mo双相包覆SiC纤维对复合材料微观结构和拉伸行为的影响。结果表明，SiCf/C/Mo/Ti2AlNb 复合材料的界面热稳定性和完整性明显优于 SiCf/C/Ti2AlNb 复合材料，因为 C/Mo 双相涂层可以减少脆性 α2 相的形成。与 C 单涂层相比，降低了 SiCf/Ti2AlNb 复合材料的界面热残余应力。1080℃/1h/850℃/20h热处理后，SiCf/C/Mo/Ti2AlNb复合材料基体主要转变为B2+O均相混合物和少量α2相，抗拉强度测试了复合材料的拉伸性能，这表明复合材料的拉伸性能在固溶时效处理后保持不变。因为与 C 单涂层相比，C/Mo 双相涂层可以减少脆性 α2 相的形成并减轻 SiCf/Ti2AlNb 复合材料的界面热残余应力。1080℃/1h/850℃/20h热处理后，SiCf/C/Mo/Ti2AlNb复合材料基体主要转变为B2+O均相混合物和少量α2相，抗拉强度测试了复合材料的拉伸性能，这表明复合材料的拉伸性能在固溶时效处理后保持不变。因为与 C 单涂层相比，C/Mo 双相涂层可以减少脆性 α2 相的形成并减轻 SiCf/Ti2AlNb 复合材料的界面热残余应力。1080℃/1h/850℃/20h热处理后，SiCf/C/Mo/Ti2AlNb复合材料基体主要转变为B2+O均相混合物和少量α2相，抗拉强度测试了复合材料的拉伸性能，这表明复合材料的拉伸性能在固溶时效处理后保持不变。