Fe_(45)Mn_(15)Cr_(15)Ni_(25)高熵合金室温及低温力学性能强化方式

Strengthening Methods of Room and Cryogenic Temperatures Mechanical Properties of Fe_(45)Mn_(15)Cr_(15)Ni_(25)High Entropy Alloy

通过热力学参数和相图计算、冷轧和退火工艺,开发制备了非等原子比Fe_(45)Mn_(15)Cr_(15)Ni_(25)高熵合金,并分析了合金在室温(293 K)和低温(77 K)条件下的力学性能。结果表明,单相面心立方结构(FCC)高熵合金具有优良的室温和低温力学性能,特别是在77 K下,冷轧态合金达到屈服强度1020 MPa、抗拉强度1180 MPa、断后伸长率20%的优异性能。室温再结晶合金,晶格本征应力86 MPa,霍尔佩奇(Hall-Petch)系数为534 MPa·μm^(1/2),细晶强化明显。低温冷轧态合金,应变硬化能力恢复,位错强化显著,同时强塑性提升。

In order to develop cobalt-free low-cost high entropy alloys(HEAs),non equiatomic ratio Fe_(45)Mn_(15)Cr_(15)Ni_(25)high entropy alloy was designed and prepared through thermodynamic parameters and phase diagram calculation,cold rolling and annealing processes,and the mechanical properties at ambient(293 K)and cryogenic temperatures(77 K)were analyzed.The results show that the single-phase face-centered cubic(FCC)high entropy alloy has excellent mechanical properties at room temperature and cryogenic temperatures.In particular,at 77 K,the cold-rolled alloy achieves the comprehensive properties of yield strength 1020 MPa,tensile strength 1180 MPa,and elongation 20%.For recrystallized alloy at ambient temperature,the intrinsic lattice stress is 86 MPa,the Hall-Petch coefficient is 534 MPa·μm^(1/2),and the grain boundary strengthening is obvious.For the cold-rolled alloy at cryogenic temperature,the strain hardening ability is restored,the dislocation strengthening is significant,and the strength and ductility are improved simultaneously.