Tyranno ZMI fiber/TiSi2–Si matrix composites for high-temperature structural applications
Tyranno ZMI fiber/TiSi2–Si matrix composites for high-temperature structural applications
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DOI：
10.1016/j.compositesa.2015.05.018
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发表时间：
2015-09
影响因子：
8.7
通讯作者：
T. Aoki;T. Ogasawara
中科院分区：
文献类型：
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作者：
T. Aoki;T. Ogasawara
Tyranno ZMI 纤维/TiSi2-Si 基复合材料是通过 Si-16at%Ti 合金在真空下于 1375 °C 下熔渗 (MI) 制造的。使用Si-Ti合金作为浸渗剂在1400°C以下进行MI加工并抑制非晶SiC纤维的强度下降。形成的合金基体致密，主要由 TiSi2-Si 共晶结构组成。在 1375 °C 熔渗的 TiSi2-Si 基复合材料表现出假塑性拉伸应力-应变行为，随后在~290 MPa 和~0.9% 应变下最终断裂。然而，当 MI 温度升高至 1450 °C 时，拉伸载荷下的刚度和极限强度显着降低。微观结构观察表明，这些降解归因于 MI 过程中增强纤维和热解碳界面上发生的损坏。目前的实验结果清楚地证明了低温 MI 工艺在强化 Tyranno ZMI 纤维复合材料和降低加工成本方面的有效性。
A Tyranno ZMI fiber/TiSi2–Si matrix composite was fabricated via melt infiltration (MI) of a Si–16at%Ti alloy at 1375 °C under vacuum. The Si–Ti alloy was used as an infiltrant to conduct MI processing below 1400 °C and inhibit the strength degradation of the amorphous SiC fibers. The alloy matrix formed was dense and comprised primarily of TiSi2–Si eutectic structures. The TiSi2–Si matrix composite melt-infiltrated at 1375 °C showed a pseudo-plastic tensile stress–strain behavior followed by final fracture at ∼290 MPa and ∼0.9% strain. When the MI temperature was increased to 1450 °C, however, substantial reduction in the stiffness and ultimate strength occurred under tensile loading. Microstructural observations revealed that these degradations were attributed to the damages that occurred on the reinforcing fibers and pyrolytic carbon interfaces during the MI process. The present experimental results clearly demonstrated the effectiveness of the low-temperature MI process in strengthening Tyranno ZMI fiber composites and reducing the processing cost.