Research on Oxidation Resistant ZrSi2-NbSi2 Bilayer Coatings for an Nb-Ti-Si-Cr Based Ultrahigh Temperature Alloy
Research on Oxidation Resistant ZrSi2-NbSi2 Bilayer Coatings for an Nb-Ti-Si-Cr Based Ultrahigh Temperature Alloy
复制标题
Nb-Ti-Si-Cr基超高温合金抗氧化ZrSi2-NbSi2双层涂层研究
DOI：
10.1007/s11085-015-9564-1
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发表时间：
2015
影响因子：
2.2
通讯作者：
Qiao Yanqiang
中科院分区：
文献类型：
--
作者：
Li Xuan;Guo Xiping;Qiao Yanqiang
采用先溅射Zr膜，再共沉积Si-Y膜的两步工艺，在Nb-Ti-Si-Cr基中温合金表面制备了ZrSi 2-NbSi 2双层抗氧化涂层。不同Zr膜厚制备的涂层具有相似的结构，由ZrSi 2外层、（Nb，X）Si 2（X代表Ti、Cr和Hf）中间层和（Ti，Nb）5Si 4内层组成。较高的共沉积温度（在1350 °C下的Si-Y共沉积）将在涂层的组成层之间的界面处引起裂纹。在1250 °C下暴露相同的静态氧化时间后，涂层试样的质量增加比基体合金低得多。氧化后形成了由SiO2、ZrSiO 4、ZrO 2、Al 2 O3、TiO 2和Cr2 O3组成的致密氧化膜，在1250 °C空气中氧化100 h后仍能保护试样不被氧化。
Oxidation-resistant ZrSi2–NbSi2bilayer coatings were prepared on an Nb–Ti–Si–Cr based ultrahigh temperature alloy using a two-step (first sputtering Zr film, and then Si–Y co-deposition) process. The coatings prepared with different Zr film thicknesses possess a similar structure, consisting of a ZrSi2outer layer, a (Nb,X)Si2(Xrepresents Ti, Cr and Hf) middle layer and a (Ti,Nb)5Si4inner layer. The higher co-deposition temperature (Si–Y co-deposition at 1350 °C) would cause cracks at the interfaces between the constituent layers of the coatings. The coated specimens possess much lower mass gains than the base alloy after exposure of same static oxidation times at 1250 °C. After oxidation, a dense scale consisting of a mixture of SiO2, ZrSiO4, ZrO2, Al2O3, TiO2and Cr2O3formed, which could protect the specimen from oxidation at least for 100 h at 1250 °C in air.