Microstructure and mechanical properties of joints in sintered SiC fiber-bonded ceramics brazed with Ag Cu Ti alloy
Microstructure and mechanical properties of joints in sintered SiC fiber-bonded ceramics brazed with Ag Cu Ti alloy
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DOI：
10.1016/j.msea.2012.05.110
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发表时间：
2012-11
期刊：
影响因子：
6.4
通讯作者：
M. Singh;T. Matsunaga;Hua-Tay Lin;R. Asthana;T. Ishikawa
中科院分区：
文献类型：
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作者：
M. Singh;T. Matsunaga;Hua-Tay Lin;R. Asthana;T. Ishikawa
使用含ti的Ag-Cu活性钎焊合金（Cusil-ABA®）进行了新型高导热烧结sic -多晶纤维结合陶瓷（SA-Tyrannohex®）的活性金属钎焊。采用扫描电子显微镜结合能量色散x射线能谱仪（SEM-EDS）对钎焊复合材料接头进行了表征。结果表明，选用合理的活性钎焊合金可以成功地连接该材料，获得良好的冶金性能和高完整性的接头。无论衬底材料中纤维取向的不同，均可获得均匀连续的接头。界面微观分析表明，钛与C和Si分别反应形成TiC层和Ti-Si化合物。此外，还使用单搭接偏置（SLO）剪切试验对环境和高温空气中节点的抗剪强度进行了评估。垂直型SA-Tyrannohex节理在650℃和750℃时的表观抗剪强度分别约为42MPa和25MPa。高温断裂主要发生在反应形成的TiC层与钎焊界面处。μ-FEA模拟结果表明，这可能是由于施加剪切应力时产生应力强度造成的。
Active metal brazing of a new high thermal conductivity sintered SiC-polycrystalline fiber-bonded ceramic (SA-Tyrannohex®) has been carried out using a Ti-containing Ag–Cu active braze alloy (Cusil-ABA®). The brazed composite joints were characterized using scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM–EDS). The results show that this material can be successfully joined using judiciously selected off-the shelf active braze alloys to yield metallurgically sound joints possessing high integrity. Uniform and continuous joints were obtained irrespective of differences in the fiber orientation in the substrate material. Detailed interfacial microanalysis showed that the titanium reacts with C and Si to form TiC layer and a Ti–Si compound, respectively. Furthermore, the evaluation of shear strength of the joints was also conducted at ambient and elevated temperatures in air using the single-lap offset (SLO) shear test. The perpendicular-type SA-Tyrannohex joints exhibited apparent shear strengths of about 42MPa and 25MPa at 650°C and 750°C, respectively. The fracture at the higher temperature occurred at the interface between the reaction-formed TiC layer and braze. This might be caused by generation of stress intensity when a shear stress was applied, according to μ-FEA simulation results.