Composition, Microstructure, and Mechanical Properties Evolution Behavior of Ta/Tahfc2 Laminated Composite between 1873~2673 K

Ta/TaHfC2 laminated composite shows great potential for application in extreme thermal environments. However, the evolution behavior of the composite at high temperatures is still unknown, as such, it is hard to evaluate whether Ta/TaHfC2 can serve as a structural material stably. Here, we investigated the changes in composition, microstructure, and fracture mode of Ta/TaHfC2 before and after annealing at 1873 ~ 2673 K using XRD and SEM. Results show that the interfacial reaction and grain coarsening go on inside the composite at high temperatures, making its main phases change from Ta & TaHfC2 to Ta2C & TaHfC2, Ta4C3 &TaHfC2, and TaC & TaHfC2 in turn and the porosity gradually increased. The flexural strength of Ta/TaHfC2 decreased at high temperatures but it owns a high strength value of 314 ± 32 MPa with a retention rate is 86% after annealing at 2473 K for 10 min.

Keywords: Ta, TaHfC2, laminated composite, high-temperature evolution behavior

Suggested Citation: Suggested Citation

Xiao, Peng and DAI, Hongliang and Li, Zhi-Jian and Yu, Yiping and Wang, Song, Composition, Microstructure, and Mechanical Properties Evolution Behavior of Ta/Tahfc2 Laminated Composite between 1873~2673 K. Available at SSRN: https://ssrn.com/abstract=4662316 or http://dx.doi.org/10.2139/ssrn.4662316