Tang Guangquan, Shao Xu, Pang Jingyu, Ji Yu, Wang Aimin, Li Jinguo, Zhang Haifeng, Zhang Hongwei
Shi-Changxu Innovation Center for Advanced Materials, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
School of Metallurgy, Northeastern University, Shenyang 110819, China.
Materials (Basel). 2023 Dec 11;16(24):7592. doi: 10.3390/ma16247592.
The NbTiAlZrHfTaMoW refractory high-entropy alloy (RHEA) system with the structure of the B2 matrix (antiphase domains) and antiphase domain boundaries was firstly developed. We conducted the mechanical properties of the RHEAs at 298 K, 1023 K, 1123 K, and 1223 K, as well as typical deformation characteristics. The RHEAs with low density (7.417.51 g/cm) have excellent compressive-specific yield strength (σYS/ρ) at 1023 K (131 MPa·cm/g) and 1123 K (~104.2 MPa·cm/g), respectively, which are far superior to most typical RHEAs. And, they still keep appropriate plastic deformability at room temperature (ε > 0.35). The superior specific yield strengths are mainly attributed to the solid solution strengthening induced by the Zr element. The formation of the dislocation slip bands with 111 and 111 directions and their interaction provide considerable plastic deformation capability. Meanwhile, dynamic recrystallization and dislocation annihilation accelerate the continuous softening after yielding at 1123 K.
首次开发了具有B2基体（反相畴）和反相畴界结构的NbTiAlZrHfTaMoW难熔高熵合金（RHEA）体系。我们研究了RHEA在298K、1023K、1123K和1223K下的力学性能以及典型的变形特征。密度较低（7.417.51g/cm）的RHEA在1023K（131MPa·cm/g）和1123K（~104.2MPa·cm/g）时分别具有优异的抗压比屈服强度（σYS/ρ），远优于大多数典型的RHEA。并且，它们在室温下仍保持适当的塑性变形能力（ε>0.35）。优异的比屈服强度主要归因于Zr元素引起的固溶强化。具有111和111方向的位错滑移带的形成及其相互作用提供了相当大的塑性变形能力。同时，动态再结晶和位错湮灭加速了1123K屈服后的持续软化。
