Kinetics and mechanism of interfacial reaction in SCS-6 SiC continuous fiber-reinforced Ti-Al intermetallic matrix composites

• Published in: Transactions of Nonferrous Metals Society of China Vol. 16; no. 1; pp. 77 - 83
• Main Author: 吕祥鸿 杨延清 马志军 刘翠霞 陈彦 艾云龙
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2006; State Key Laboratory of Solidification Processing, Northwestern Polytechnical University,Xi'an 710072, China%College of Materials Engineering, Nanchang Institute of Aero-technology,Nanchang 330034, China
• Subjects: activation energy; interfacial reaction; kinetics; SCS-6 SiC fiber; Ti-Al intermetallics; Ti-Al合金; 动力学; 界面反应; 碳化硅纤维; 金属基复合材料; activation energy; SCS-6 SiC fiber; interfacial reaction; kinetics; Ti-Al intermetallics
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(06)60014-9

SCS-6 SiC continuous fiber-reinforced Ti-Al intermetallics-matrix composites were fabricated by HIP method and then heat-treated in vacuum under different conditions. The interfacial reaction kinetics and mechanism were studied by using SEM, EDS and XRD. The results show that the content fluctuation of reactive elements such as C, Ti and Si appears in interfacial reaction layers, and multi-layer interfacial reaction compounds form. Alloying element Nb in matrix remarkably diffuses into interfacial reaction zone and changes the activation energy for the interfacial reaction layer growth following a role of parabolic rate. The activation energy （Qk） and （k0） of SCS-6 SiC/super α2 and SCS-6 SiC/Ti2AlNb are 317.664 kJ/mol, 175.709 kJ/mol and 5.4438X 10^-2m/s^1/2, 1.44× 10^-5 m/s^1/2; respectively, and the diffusion coefficient （Dc） is about 10^-18--10^-20 m^2/s. It is confirmed that the SCS-6 SiC/Ti-Al intermetallic composites have higher interface compatibility and stability. Furthermore, compared with SCS-6 SiC/super α2, the interface compatibility and stability of SCS-6 SiC/Ti2AINb are even higher.