Microstructure, mechanical properties and oxidation behavior of TaC- and HfC-based materials containing short SiC fiber
Microstructure, mechanical properties and oxidation behavior of TaC- and HfC-based materials containing short SiC fiber
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DOI：
10.1016/j.ceramint.2014.09.070
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发表时间：
2015
影响因子：
5.2
通讯作者：
L. Pienti;L. Silvestroni;E. Landi;C. Melandri;D. Sciti
中科院分区：
文献类型：
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作者：
L. Pienti;L. Silvestroni;E. Landi;C. Melandri;D. Sciti
在1700-1750 °C下热压制备了含15vol% SiC短纤维增强相的TaC和HfC基复合材料。选择合适的烧结添加剂，以便在SiC纤维良好耐受的温度下获得完全致密化。显微结构表征概述了碳化物基体和SiC纤维之间的强相互作用。评估以下性质：维氏硬度、通过人字形切口梁的断裂韧性、弹性模量、在室温和1200 °C下的4-pt弯曲强度、在Ar中高达1300 °C的线性CTE和在Ar中高达1900 °C的热导率。在空气中的氧化测试用热重分析在高达1500 °C下和在1600 °C下在自下而上的炉中进行。与HfC相比，TaC基材料通常具有更高的热机械性能，但抗氧化性较低。纤维增强复合材料的性能进行了比较，那些未增强的。
TaC- and HfC-based composites containing 15 vol% short SiC fibers as reinforcing phase were produced by hot pressing at 1700–1750 °C. Suitable sintering additives were selected in order to get a full densification at temperatures well-tolerated by SiC fibers. Microstructural characterization outlined a strong interaction between the carbide matrix and SiC fibers. The following properties were evaluated: Vickers hardness, fracture toughness by chevron notched beams, elastic modulus, 4-pt bending strength at room temperature and at 1200 °C, linear CTE up to 1300 °C in Ar, and thermal conductivity up to 1900 °C in Ar. Oxidation tests in air were carried out with thermogravimetric analysis up to 1500 °C and in a bottom up furnace at 1600 °C. TaC-based materials generally possessed higher thermo-mechanical properties compared to HfC, but lower oxidation resistance. Properties of fiber-reinforced composites were compared to those of unreinforced ones.