田钊,陈维平,王浩,付志强

• 1:华南理工大学广东省金属新材料制备与成形重点实验室

摘要(Abstract)：

通过真空电弧熔炼法制备了Ti_(47-x)Nb_(23)Cr_(18)V_(12)Zr_x(x=0、4、8、12 at%)系难熔高熵合金，随后在1200℃下保温12 h对合金进行均匀化热处理。利用X射线衍射(XRD)、扫描电镜(SEM)、万能力学试验机和显微硬度仪等研究了铸态与均匀化热处理态合金的相组成、微观组织及力学性能。结果表明：Zr元素的添加使铸态合金在枝晶间析出C15结构的Cr_2(Ti, Nb, V,Zr)-Laves相，同时，Zr元素含量的增加增强了合金的压缩屈服强度和硬度，但使其塑性降低。均匀化热处理并未改变合金的相组成，但使合金的组织形貌发生了明显改变，并大大增加了析出相的体积分数。经过均匀化热处理后，合金的强度和硬度有所降低，但塑性得到改善。其中，Ti_(43)Cr_(18)Nb_(23)V_(12)Zr_4合金的压缩塑性由铸态时的29%提升至超过50%,同时具有1110 MPa的屈服强度和高达180 MPa·cm~3·g~(-1)的屈强比，表现出优异的强度-塑性匹配。此外，得益于细小弥散的Laves相，均匀化热处理后Ti_(39)Cr_(18)Nb_(23)V_(12)Zr_8合金的屈服强度和塑性均有小幅度增强。

关键词(KeyWords)： 难熔高熵合金;均匀化热处理;微观组织;力学性能;高屈强比

Abstract:

Keywords:

基金项目(Foundation): 广东省自然科学基金-面上项目(2023A1515012363);; 广东省科学技术厅国际科技合作领域项目(2023A0505050154)

作者(Author): 田钊,陈维平,王浩,付志强

DOI: 10.13289/j.issn.1009-6264.2023-0319

参考文献(References)：

• [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].Advanced Engineering Materials,2004,6(5):299-303.
• [2] Li W D,Xie D,Li D,et al.Mechanical behavior of high-entropy alloys[J].Progress in Materials Science,2021,118:100777.
• [3] Miracle D B,Senkov O N.A critical review of high entropy alloys and related concepts[J].Acta Materialia,2017,122:448-511.
• [4] Cantor B.Multicomponent high-entropy Cantor alloys[J].Progress in Materials Science,2021,120:100754.
• [5] Sathiyamoorthi P,Kim H S.High-entropy alloys with heterogeneous microstructure:Processing and mechanical properties[J].Progress in Materials Science,2022,123:100709.
• [6] Wang J,Bai S,Tang Y,et al.Effect of the valence electron concentration on the yield strength of Ti-Zr-Nb-V high-entropy alloys[J].Journal of Alloys and Compounds,2021,868:159190.
• [7] Ge S,Fu H,Zhang L,et al.Effects of Al addition on the microstructures and properties of MoNbTaTiV refractory high entropy alloy[J].Materials Science and Engineering A,2020,784:139275.
• [8] Tang Z,Yuan T,Tsai C,et al.Fatigue behavior of a wrought Al0.5CoCrCuFeNi two-phase high-entropy alloy[J].Acta Materialia,2015,99:247-258.
• [9] Zhou Y J,Zhang Y,Wang Y L,et al.Solid solution alloys of AlCoCrFeNiTix with excellent room-temperature mechanical properties[J].Applied Physics Letters,2007,90(18):253-257.
• [10] Gludovatz B,Hohenwarter A,Catoor D,et al.A fracture-resistant high-entropy alloy for cryogenic applications[J].Science,2014,345(6201):1153-1158.
• [11] Crewal H S,Sanjiv R M,Arora H S,et al.Activation energy and high temperature oxidation behavior of multi-principal element alloy[J].Advanced Engineering Materials,2017,19(11):1700182.
• [12] Senkov O N,Wilks G B,Miracle D B,et al.Refractory high-entropy alloys[J].Intermetallics,2010,18(9):1758-1765.
• [13] Senkov O N,Woodward C,Miracle D B.Microstructure and properties of aluminum-containing refractory high-entropy alloys[J].Journal of the Minerals Metals and Materials Society,2014,66:2030-2042.
• [14] Schuh B,Voelker B,Todt J,et al.Thermodynamic instability of a nanocrystalline,single-phase TiZrNbHfTa alloy and its impact on the mechanical properties[J].Acta Materialia,2018,142:201-212.
• [15] Stepanov N D,Shaysultanov D C,Salishchev G A,et al.Structure and mechanical properties of a lightweight AlNbTiV high entropy alloy[J].Materials Letters,2015,142:153-155.
• [16] Senkov O N,Senkova S V,Miracle D B,et al.Mechanical properties of low-density,refractory multi-principal element alloys of the Cr-Nb-Ti-V-Zr system[J].Materials Science and Engineering A,2013,565:51-62.
• [17] Troparevsky M C,Morris J R,Daene M,et al.Beyond atomic sizes and Hume-Rothery rules:Understanding and predicting high-entropy alloys[J].Journal of the Minerals Metals and Materials Society,2015,67:2350-2363.
• [18] Zhang Y,Zhou Y J,Lin J P,et al.Liaw solid-solution phase formation rules for multi-component alloys[J].Advanced Engineering Materials,2008,10(6):534-538.
• [19] Poletti M,Battezzati L.Electronic and thermodynamic criteria for the occurrence of high entropy alloys in metallic systems[J].Acta Material,2014,75:297-306.
• [20] Guo S,Ng C,Lu J,et al.Effect of valence electron concentration on stability of fcc or bcc phase in high entropy alloys[J].Journal of Applied Physics,2011,109(10):213.
• [21] Yang X,Zhang Y.Prediction of high-entropy stabilized solid-solution in multi-component alloys[J].Materials Chemistry and Physics,2012,132(2):233-238.
• [22] Sheikh S,Shafeie S,Hu Q,et al.Alloy design for intrinsically ductile refractory high-entropy alloys[J].Journal of Applied Physics,2016,120(16):164902.
• [23] Yurchenko N Y,Stepanov N D,Zherebtsov S V,et al.Structure and mechanical properties of B2 ordered refractory AlNbTiVZrx (x=0-1.5) high-entropy alloys[J].Materials Science and Engineering A,2017,704:82-90.
• [24] Fazakas E,Zadorozhnyy V,Varga L K,et al.Experimental and theoretical study of Ti20Zr20Hf20Nb20X20 (X=V or Cr) refractory high-entropy alloys[J].International Journal of Refractory Metals and Hard Materials,2014,47:131-138.
• [25] Senkov O N,Scott J M,Senkova S V,et al.Microstructure and room temperature properties of a high-entropy TaNbHfZrTi alloy[J].Journal of Alloys and Compounds,2011,509(20):6043-6048.
• [26] Yao H,Qiao J W,Gao M C,et al.MoNbTaV medium-entropy alloy[J].Entropy,2016,18:189.
• [27] Yang X,Zhang Y,Liaw P K.Microstructure and compressive properties of NbTiVTaAlx high entropy alloys[J].Procedia Engineering,2012,36:292-298.
• [28] Wu Y D,Cai Y H,Chen X H,et al.Phase composition and solid solution strengthening effect in TiZrNbMoV high-entropy alloys[J].Materials and Design,2015,83:651-660.

文章评论(Comment)：