NiAl改性C/C复合材料的组织、力学性能和氧化行为（英文）

Microstructures,mechanical and oxidation behaviors of C/C composites modified by NiAl alloy

以NiAl和钛的混合粉为原料,采用真空熔渗法制备了NiAl改性C/C复合材料,利用扫描电镜观察了复合材料的显微组织,分析了其断裂行为、渗透机制和氧化机制。结果表明:界面反应形成的TiC提高了NiAl对C/C多孔体的润湿性,且均匀致密的Py C/TiC/NiAl+TiC多层空间管状网络结构包覆在碳纤维表面,而NiAl合金的渗透深度则取决于热解碳与钛的反应。复合材料倾向于在NiAl渗透层和未渗透的C/C界面处断裂。经1773 K氧化30 min后的复合材料表面生成钛酸铝(Al_2TiO_5)和氧化钛(TiO_2),内部的多层空间管状网络结构得以部分保留。

Carbon/carbon composites modified by NiAl alloy were prepared using vacuum reactive melt infiltration methods with NiAl and titanium mixed powders as raw materials. The microstructures were investigated by scanning electron microscopy. The fracture behavior, infiltration and oxidation mechanism were further discussed. The results indicated that NiAl alloy exhibited good wettability on the C/C preform because a TiC reaction layer formed at the interface. Multi-layer（PyC/TiC/NiAl＋TiC） coating evenly and compactly distributed on the surface of the carbon fiber in tubular form. The penetration depth of molten NiAl alloys depended on the reaction between the PyC and titanium. The impact fracture was inclined to along the interface between the NiAl permeability layer and C/C matrix. Al_2TiO_5 and TiO_2 formed on the surface, while the interior multi-layer tubular structure partially remained after oxidation at 1773 K for 30 min.