文献类型：期刊文献

英文题名：Ti-content-regulated microstructural evolution and mechanisms underlying room-temperature compressive strength-plasticity synergy in NbMoTaWTix refractory high-entropy alloys

作者：Hu, Jiezhen[1,3];Zhong, Shenghao[1];Geng, Baoyu[1,3];Deng, Peichang[2,3];Li, Youchi[1];Wen, Cheng[1]

机构：[1]Guangdong Ocean Univ, Sch Mech Engn, Zhanjiang 524088, Peoples R China;[2]Guangdong Ocean Univ, Coll Chem & Environm, Zhanjiang 524088, Guangdong, Peoples R China;[3]Zhanjiang Key Lab Corrosion & Protect Ocean Engn E, Zhanjiang 524088, Guangdong, Peoples R China

年份：2026

卷号：1081

外文期刊名：JOURNAL OF ALLOYS AND COMPOUNDS

收录：SCI-EXPANDED(收录号：WOS:001884417100001)、、WOS

基金：We gratefully acknowledge the financial support for this project provided by the following grants: Scientific research start-up funds of Guangdong Ocean University, Grant No. 060302062101 and No. 060302062402; and the Innovation Team Project for Ordinary Universities in Guangdong Province, Grant No. 2024KCXTD041. We would like to thank the Analytical and Testing Center of Guangdong Ocean University for providing data processing services and technical support.

语种：英文

外文关键词：NbMoTaWTix refractory high-entropy alloys; Phase stability; Microstructural evolution; First-principles calculations; Compressive strength-plasticity synergy

外文摘要：To reveal the effects of Ti content on the phase stability, microstructural evolution, and room-temperature compressive behavior of NbMoTaW-based refractory high-entropy alloys, a series of as-cast NbMoTaWTix (x = 0, 0.5, 1, 2, and 4) alloys were fabricated and systematically investigated through microstructural characterization, mechanical testing, and first-principles calculations. The results show that all the alloys retain a single-phase BCC solid-solution structure without detectable secondary phases; with increasing Ti content, the lattice parameter increases from 3.2266 & Aring; to 3.2528 & Aring;, the dendritic microstructure is progressively refined, and elemental partitioning becomes more pronounced. The hardness decreases from 552.5 HV to 463.4 HV, whereas the ultimate compressive strength and fracture strain increase from 1230 MPa and 5.2% to 2210 MPa and 36.8%, respectively. First-principles calculations based on representative SQS models indicate that Ti addition reduces the bulk modulus, shear modulus, Young's modulus, and theoretical hardness, while weakening directional bonding and enhancing metallic bonding characteristics, suggesting Ti-induced elastic softening and reduced resistance to shear deformation. The simultaneous improvement in ultimate compressive strength and fracture strain is attributed to the retained stability of the BCC solid-solution, dendrite refinement, and the load-bearing and deformation-coordination mechanism between Ta/W-enriched dendrite cores and Ti/Nb-enriched interdendritic regions. These findings clarify the mechanisms underlying the Ti-content-regulated room-temperature compressive strength-plasticity synergy in NbMoTaWTix refractory high-entropy alloys.