Strong ZrC ceramics at high temperatures with the addition of W
Strong ZrC ceramics at high temperatures with the addition of W
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添加 W 后的高温高强度 ZrC 陶瓷
DOI：
10.1111/jace.16320
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发表时间：
2019
影响因子：
3.9
通讯作者：
Jiang Dan-Yu
中科院分区：
文献类型：
--
作者：
Shen Yi-Bo;Wang Xin-Gang;Zhang Guo-Jun;Xue Jia-Xiang;Li Qiang;Jiang Dan-Yu
研究了W添加对ZrC陶瓷致密化、显微结构和力学性能的影响。 W与ZrC中的碳反应生成WC，在1300-1700℃形成ZrC1-x，而WC在1800-2000℃进一步溶解在ZrC中形成(Zr1-yWy)C1-x固溶体。含 5 mol% W 的 ZrC（ZW5，96.8%）的相对密度明显高于纯 ZrC（Z0，94.8%）。 ZW5 表现出精细均匀的微观结构，晶粒尺寸 (2.6 ± 0.5 μm) 远小于 Z0 (10.9 ± 3.0 μm)，而 ZrC 中过量的 W 添加 (10 mol%) 对致密化和微观结构产生不利影响。 Z0 的弯曲强度在室温下为 446 ± 46 MPa，在高纯度流动氩气氛中在 1800°C 时几乎线性下降至 281 ± 10 MPa。 ZW5的室温弯曲强度为512±40MPa，即使达到1800℃也没有退化。 ZW5细小均匀的微观结构和晶界氧杂质的去除促进了高温力学性能的提高。
The effect of W addition on densification, microstructure, and mechanical properties of ZrC ceramics was investigated. W reacted with carbon in ZrC to form WC, which resulted in the formation of ZrC1‐xat 1300‐1700°C, while WC was further dissolved in ZrC to form a (Zr1‐yWy)C1‐xsolid solution at 1800‐2000°C. The relative density of ZrC with 5 mol% W (ZW5, 96.8%) was markedly higher than that of pure ZrC (Z0, 94.8%). ZW5 exhibited a fine homogeneous microstructure with a grain size (2.6 ± 0.5 μm) much smaller than that of Z0 (10.9 ± 3.0 μm), while excess W addition (10 mol%) in ZrC adversely affected the densification and the microstructure. The flexure strength of Z0 was 446 ± 46 MPa at room temperature, which almost linearly decreased to 281 ± 10 MPa at 1800°C in a high‐purity flowing argon atmosphere. The flexure strength of ZW5 was 512 ± 40 MPa at room temperature, and had no degradation even up to 1800°C. The fine and homogeneous microstructure of ZW5 and the removal of oxygen impurity from the grain boundaries promoted the enhancement of high‐temperature mechanical properties.