The influence of Ti content and temperature on the mechanical behavior of FeNiCrCoTix high-entropy alloys under tensile and compressive loads: A molecular dynamics simulation study
-
摘要: 针对FeNiCrCoAl、FeNiCrCoCu、FeNiCrCoMn等高熵合金(HEA)力学性能的研究已得到广泛的开展,但掺杂Ti元素的高熵合金仍缺乏系统性研究。在该方向中,对FeNiCrCoTi系高熵合金的压缩力学行为及其原子尺度内在机制的关注度持续提升。研究通过分子动力学(MD)模拟,全面探究了Ti含量(4%~10%)与温度(100~500 K)对FeNiCrCoTi高熵合金拉伸和压缩力学性能的影响。研究结果揭示了高熵合金在力学响应中的拉压不对称性。在不同的Ti含量下,T3(x=0.3)模型的性能最好,T3模型的位错密度最高,导致位错之间缠绕、塞积,从而提高了抗拉强度。而在压缩载荷下,C2(x=0.2)模型的性能最好,在C2模型中观察到高密度的位错形成了位错网络,最终导致合金抗压强度最高。合金的抗拉压强度随着温度的升高而单调递减,这是由于温度升高原子热运动加剧,降低了晶界阻碍作用,使位错克服晶格阻力,更容易移动,使得材料在较高温度下发生软化现象。综上所述,该研究为探究FeNiCrCoTi HEA的力学性能开启了一扇新的大门,为该材料在不同Ti元素含量和温度下的应用提供了理论依据。Abstract: Extensive investigations have been conducted currently into the mechanical properties of high-entropy alloys (HEAs), such as FeNiCrCoAl、FeNiCrCoCu、FeNiCrCoMn, etc. While the HEAs doped with Ti element are still lack of systematic research. In this field, the compressive mechanical behavior and intrinsic mechanism in atomic scale of FeNiCrCoTi HEAs have attracted increasing attention. Molecular dynamics (MD) simulations were used to comprehensively investigate how titanium content (4%~10%) and temperature (100~500 K) affect the FeNiCrCoTix HEA’s tensile and compressive mechanical properties. The findings highlight a tension–compression asymmetry in the mechanical response of HEAs. Among the different Ti contents, the T3 (x = 0.3) model exhibits the best performance, which is linked to the highest dislocation density, facilitating dislocation entanglement and accumulation, thereby enhancing tensile strength. In contrast, under compressive loading, the C2 model (x = 0.2) demonstrates optimal performance. This phenomenon is attributed to the formation of dislocation network by high-density dislocations within the C2, which contributes to its highest compressive strength. Both tensile and compressive strengths of the HEAs exhibit a monotonic decrease as temperature rises, which is attributed to the intensified atomic thermal motion with increasing temperatures, weakening grain boundary resistance and facilitating dislocation motion across lattice barriers, thus softening the materials at elevated temperatures. Collectively, this investigation offers critical insights into the mechanical behavior of FeNiCrCoTi HEAs and provides a theoretical basis for material applications via Ti content and temperature control.
-
表 1 拉伸和压缩载荷作用下合金模型原子比例
Table 1. Atomic proportions in alloy models under tensile and compressive loads
Tensile Compression Atomic content/% Fe Ni Cr Co Ti T2 C2 24 24 24 24 4 T3 C3 23.5 23.5 23.5 23.5 6 T4 C4 23 23 23 23 8 T5 C5 22.5 22.5 22.5 22.5 10 -
[1] Yeh J W, Chen S K, Lin S J, et al. Nanostructured high-entropy alloys with multiple principal elements: novel alloy design concepts and outcomes[J]. Adv Eng Mater, 2004, 6(5): 299-303. [2] Zou Yu, Maiti S, Steurer W, et al. Size-dependent plasticity in an Nb25Mo25-Ta25W25 refractory high-entropy alloy[J]. Acta Mater, 2014, 65: 85-97. [3] Yao M J, Pradeep K G, Tasan C C, et al. A novel, single phase, non-equiatomic FeMnNiCoCr high-entropy alloy with exceptional phase stability and tensile ductility[J]. Scripta Mater, 2014: 72-73: 5-8. [4] Zhang Lijun, Yu Pengfei, Cheng Hu, et al. Nanoindentation creep behavior of an Al0.3CoCrFeNi high-entropy alloy[J]. Metall Mater Trans A, 2016, 47: 5871-5875. doi: 10.1007/s11661-016-3469-8 [5] Zhao Chendong, Li Jinshan, Liu Yudong, et al. Optimizing mechanical and magnetic properties of AlCoCrFeNi high-entropy alloy via FCC to BCC phase transformation[J]. J Mater Sci Technol, 2021, 86: 117-126. [6] Yeh J, Chen S, Lin S J, et al. Nanostructured high-entropy alloys with multiple principal elements: novel alloy design concepts and outcomes[J]. Adv Eng Mater, 2004, 6(5): 299-303. [7] Chen Weiping, Fu Zhiqiang, Fang Sicong, et al. Alloying behavior, microstructure and mechanical properties in a FeNiCrCo0.3Al0.7 high entropy alloy[J]. Materials and Design, 2013, 51: 854-860. [8] Chuang Minghao, TSAI Minghung, Wang Woeiren, et al. Microstructure and wear behavior of AlxCo1.5CrFeNi1.5Tiy high-entropy alloys[J]. Acta Mater, 2011, 59(16): 6308-6317. [9] Shen Yixi, Spearot D. Mobility of dislocations in FeNiCrCoCu high entropy alloys[J]. Model Simul Mater Sc, 2021, 29: 085017. [10] Huang E W, Yu D J, Yeh J, et al. A study of lattice elasticity from low entropy metals to medium and high entropy alloys[J]. Scripta Mater, 2015, 101: 32-35. [11] Cao Ronggen, Deng Chuang. The ultra-small strongest grain size in nanocrystalline Ni nanowires[J]. Scripta Mater, 2015, 94: 9-12. [12] Osetsky Y N, Bacon D J. Atomic-scale mechanisms of void hardening in bcc and fcc metals[J]. Philos Mag, 2010, 90(7-8): 945-961. doi: 10.1080/14786430903164580 [13] Osetsky Y N, Bacon D J. An atomic-level model for studying the dynamics of edge dislocations in metals[J]. Model Simul Mater Sc, 2003, 11: 427. [14] Veiga R G A, Goldenstein H, Perez M, et al. Monte Carlo and molecular dynamics simulations of screw dislocation locking by Cottrell atmospheres in low carbon Fe–C alloys[J]. Scripta Mater, 2015, 108: 19-22. [15] Mendelev M I, Kramer M J, Ott R. Molecular dynamics simulation of diffusion in supercooled Cu–Zr alloys[J]. philos Mag, 2009, 89: 109-126. [16] Bomarito G F, Lin Y, Waener D H. An atomistic modeling survey of the shear strength of twist grain boundaries in aluminum[j]. Scripta Mater, 2015, 101: 72-75. [17] Smith T M, Hooshmand M S, Esser B D, et al. Atomic-scale characterization and modeling of 60 dislocations in a high-entropy alloy[J]. Acta Mater, 2016, 110: 352-363. [18] Wang Z, Gao M C, Ma S G, et al. Effect of cold rolling on the microstructure and mechanical properties of Al0.25CoCrFe1.25Ni1.25 high-entropy alloy[J]. Mater Sci Eng A, 2015, 645: 163-169. [19] Tang Zhi, Senkov O N, Pariosh C M, et al. Tensile ductility of an AlCoCrFeNi multi-phase highentropy alloy through hot isostatic pressing (HIP) and homogenization[J]. Mater Sci Eng A, 2015, 647: 229-240. [20] Munitz A, Salhov S, Hayun S, et al. Heat treatment impacts the microstructure and mechanical properties of AlCoCrFeNi high entropy alloy[J]. J Alloy Compd, 2016, 683: 221-230. [21] Dqbrowa J, Kucza W, Cie´slak G, et al. Interdiffusion in the FCC-structured Al-Co-Cr-Fe-Ni high entropy alloys: experimental studies and numerical simulations[J]. J Alloy Compd, 2016, 674: 455-462. [22] Licavoli J J, Gao M, Sears J S, et al. Microstructure and mechanical behavior of high-entropy alloys[J]. J Mater Eng Perform, 2015, 24: 3685-3698. [23] Gludovatz B, Hohenwarter A, Catoop D, et al. A fracture-resistant high-entropy alloy for cryogenic applications[J]. Science, 2014, 345: 1153-1158. [24] Zou Yu, Maiti S, Steurer W, et al. Size-dependent plasticity in an Nb25Mo25Ta25W25 refractory high-entropy alloy[J]. Acta Mater, 2014, 65: 85-97. doi: 10.1016/j.actamat.2013.11.049 [25] Li Anmin, Zhang Xiyan. Thermodynamic analysis of the simple microstructure of AlCrFeNiCu high-entropy alloy with multi-principal elements[J]. Acta Metall Sin-Engl, 2009, 22(3): 219-224. [26] Ma S G, Jiao Z M, Qiao J W, et al. Strain rate effects on the dynamic mechanical properties of the AlCrCuFeNi2 high-entropy alloy[J]. Mater Sci Eng A, 2016, 649: 35-38. [27] Tasan C C, Deng Y, Pradeep K G, et al. Composition dependence of phase stability, deformation mechanisms, and mechanical properties of the CoCrFeMnNi high-entropy alloy system[J]. Jom-Us, 2014, 66: 1993-2001. [28] Shun Taotsung, Du Yuchin. Age hardening of the Al0.3CoCrFeNiC0.1 high entropy alloy[J]. J Alloy Compd, 2009, 478: 269-272. [29] Sun Zhihui, Zhang Jie, Gao Xinxin, et al. Tensile mechanical properties of CoCrFeNiTiAl high entropy alloy via molecular dynamics simulations[J]. Intermetallics, 2022, 142: 107444. [30] Cheng Wei, Zhao Hongliang, Luo Zichao, et al. Atomic-scale investigation of Ti element regulating the mechanical and tribological performance of FeCrNi MEA[J]. Tribol Int, 2025, 207: 110604. [31] Luo Zelong, Wu Lianjun, Ma Lian, et al. Molecular dynamics simulations of mechanical properties and phase structure for CoCrFeNiTix high-entropy alloys[J]. Mater Today Commun, 2025, 43: 111789. [32] Gong Zheyu, Yang Lixiao, Cao Yong, et al. The influence of Mn content, temperature, and strain rate on the mechanical behavior of FeNiCrCoMn high-entropy alloys under tensile and compressive loads: A molecular dynamics simulation study[J]. Mater Today Commun, 2025, 46: 112532. [33] Qi Yuming, Zhao Min, Feng Miaolin. Molecular simulation of microstructure evolution and plastic deformation of nanocrystalline CoCrFeMnNi high-entropy alloy under tension and compression[J]. J Alloy Compd, 2021, 851: 156923. [34] Plimpton S. Fast parallel algorithms for short-range molecular dynamics[J]. J Comput Phys, 1995, 117(1): 1-19. [35] Farkas D, Caro A. Model interatomic potentials for Fe–Ni–Cr–Co–Al high-entropy alloys[J]. J Mater Res, 2020, 35: 3031-3040. [36] Wu Yonglong, Tan Jing, Li Xinmin, et al. Molecular dynamics study on friction of high-entropy alloy FeNiCrCoCu[J]. Mater Today Commun, 2023, 37: 107107. [37] Stukowski A. Visualization and analysis of atomistic simulation data with OVITO–the Open Visualization Tool[J]. Model Simul Mater Sci Eng, 2010, 18: 015012. [38] Jiang Shan, Zhang Hongwu, Zheng Yonggang, et al. Atomistic study of the mechanical response of copper nanowires under torsion[J]. J Phys D Appl Phys, 2009, 42: 135408. [39] Li Duo, Wang Fengchao, Yang Zhenyu, et al. How to identify dislocations in molecular dynamics simulations?[J]. Sci China Phys Mech, 2014, 57: 2177-2187. [40] Zheng Wei, Han Junzhao, Duan Xing, et al. Mechanical properties of Al0.1CoCrFeNi high entropy alloy based on molecular dynamics study[J]. Rare Metal Mat Eng, 2022, 51: 3230-3235. [41] Koh S, Lee H P, Lu C, et al. Molecular dynamics simulation of a solid platinum nanowire under uniaxial tensile strain: temperature and strain-rate effects[J]. Phys Rev B, 2005, 72: 85414. [42] Argon A S, Kuo H Y. Plastic flow in a disordered bubble raft (an analog of a metallic glass)[J]. Mater Sci Eng, 1979, 39(1): 10. [43] Hanan J. Amorphous metal sandwich composites with unprecedented strength[C]//Composites at Lake Louise (CALL 2015). Lake Louise, 2015: 8-12. [44] Yang Zhibiao, Lu Song, Tian Yanzhong, et al. Theoretical and experimental study of phase transformation and twinning behavior in metastable high-entropy alloys[J]. J Mater Sci Technol, 2022, 99: 161-168. [45] Zhou Kai, Liu Bin, Shao Shaofeng, et al. Molecular dynamics simulations of tension–compression asymmetry in nanocrystalline copper[J]. Phys Lett A, 2017, 381: 1163-1168. [46] Yang Zailin, Zhang Guowei, Zhao Jianwei, et al. Molecular dynamics simulations of void effect of the copper nanocubes under triaxial tensions[J]. Phys Lett A, 2016, 380: 917-922. [47] Lee C, Song G, Gao M, et al. Lattice distortion in a strong and ductile refractory high-entropy alloy[J]. Acta Mater, 2018, 160: 158-172. -
下载: