以Cr、Co、Fe、Ni单质块体和Cr3C2为原料,采用气雾化法制备预合金粉,通过热等静压法制备CoCrFeNiC0.05高熵合金,对合金进行热轧和退火处理,结合X射线衍射、金相显微镜、扫描电子显微镜、透射电子显微镜、电子背散射衍射、硬度测试和拉伸性能测试等手段,研究退火处理对粉末冶金CoCrFeNiC0.05高熵合金热轧板显微组织和力学性能的影响。结果表明:热轧变形后,合金晶粒形态由热等静压的等轴状转变为条带状,织构组态以F织构为主,晶内存在孪晶和亚微米级Cr23C6碳化物。经800 ℃退火处理后,合金发生完全再结晶。热轧结合中温退火(500 ℃)是获得具有良好综合力学性能CoCrFeNiC0.05高熵合金的有效途径,合金的屈服强度为961 MPa,抗拉强度为1 023 MPa,伸长率为13.6%。
The pre-alloyed powder was prepared by gas atomization method with Cr, Co, Fe, Ni simple substance and Cr3C2 as raw materials. CoCrFeNiC0.05 high-entropy alloy was prepared by hot isostatic pressing, and the alloy was hot rolled and annealed. The effects of annealing on the microstructure and mechanical properties of powder metallurgy hot rolled CoCrFeNiC0.05 high-entropy alloy sheet were systematically studied by X-ray diffraction, optical microscope, scanning electron microscope, transmission electron microscope, electron backscatter diffraction, Vickers hardness, and tensile testing. The results show that the grains are equiaxed in hot isotactic pressed alloy but transform to elongated morphology after hot rolling. The hot rolled sheet exhibits a strong F-type texture, and twins and submicron Cr23C6 typed carbide are observed. After annealing treatment at 800 ℃, the alloy undergoes complete recrystallization. Hot rolling combining with moderate temperature annealing (500 ℃) is an effective approach to achieving good comprehensive mechanical properties for CoCrFeNiC0.05 high-entropy alloy, with yield strength of 961 MPa, tensile strength of 1 023 MPa, and elongation of 13.6%.
[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] YE Y F, WANG Q, LU J, et al.High-entropy alloy: challenges and prospects[J]. Materials Today, 2016, 19(6): 349-362.
[3] ZHANG C, YU Q, TANG Y T, et al.Strong and ductile FeNiCoAl-based high-entropy alloys for cryogenic to elevated temperature multifunctional applications[J]. Acta Materialia, 2023, 242: 118449.
[4] GLUDOVATZ B, HOHENWARTER A, CATOOR D, et al.A fracture-resistant high-entropy alloy for cryogenic applications[J]. Science, 2014, 345(6201): 1153-1158.
[5] LIU D, YU Q, KABRA S, et al.Exceptional fracture toughness of CrCoNi-based medium- and high-entropy alloys at 20 kelvin[J]. Science, 2022, 378(6623): 978-983.
[6] EL-ATWANI O, LI N, LI M, et al. Outstanding radiation resistance of tungsten-based high-entropy alloys[J]. Science Advances, 2019, 5(3): eaav2002.
[7] CHEN W, ZHOU R, LI W, et al.Effect of interstitial carbon and nitrogen on corrosion of FeCoCrNi multi-principal element alloys made by selective laser melting[J]. Journal of Materials Science & Technology, 2023, 148: 52-63.
[8] WU Z, BEI H, PHARR G M, et al.Temperature dependence of the mechanical properties of equiatomic solid solution alloys with face-centered cubic crystal structures[J]. Acta Materialia, 2014, 81: 428-441.
[9] ZHANG B, ZHANG Y, GUO S M.A thermodynamic study of corrosion behaviors for CoCrFeNi-based high-entropy alloys[J]. Journal of Materials Science, 2018, 53(20): 14729-14738.
[10] GALI A, GEORGE E P.Tensile properties of high- and medium-entropy alloys[J]. Intermetallics, 2013, 39: 74-78.
[11] WANG Z, BAKER I, CAI Z, et al.The effect of interstitial carbon on the mechanical properties and dislocation substructure evolution in Fe40.4Ni11.3Mn34.8Al7.5Cr6 high entropy alloys[J]. Acta Materialia, 2016, 120: 228-239.
[12] LI W, XIE D, LI D, et al.Mechanical behavior of high- entropy alloys[J]. Progress in Materials Science, 2021, 118: 100777.
[13] CHEN J, YAO Z, WANG X, et al.Effect of C content on microstructure and tensile properties of as-cast CoCrFeMnNi high entropy alloy[J]. Materials Chemistry and Physics, 2018, 210: 136-145.
[14] ELKATATNY S, GEPREEL M A H, HAMADA A, et al. Effect of Al content and cold rolling on the microstructure and mechanical properties of Al5Cr12Fe35Mn28Ni20 high- entropy alloy[J]. Materials Science and Engineering A, 2019, 759: 380-390.
[15] HE Y X, YANG H X, ZHAO C D, et al.Enhancing mechanical properties of Al0.25CoCrFeNi high-entropy alloy via cold rolling and subsequent annealing[J]. Journal of Alloys and Compounds, 2020, 830: 154645.
[16] LIU Z, XIONG Z P, CHEN K X, et al.Large-size high-strength and high-ductility AlCoCrFeNi2.1 eutectic high-entropy alloy produced by hot-rolling and subsequent aging[J]. Materials Letters, 2022, 315: 131933.
[17] LU P, ZHANG T W, ZHAO D, et al.Mechanical behaviors and texture evolution of CoCrFeNi high-entropy alloy under shear-tension deformation[J]. Journal of Alloys and Compounds, 2020, 815: 152479.
[18] SALEH A A, HAASE C, PERELOMA E V, et al.On the evolution and modelling of brass-type texture in cold-rolled twinning-induced plasticity steel[J]. Acta Materialia, 2014, 70: 259-271.
[19] BHATTACHARJEE P P, SATHIARAJ G D, ZAID M, et al.Microstructure and texture evolution during annealing of equiatomic CoCrFeMnNi high-entropy alloy[J]. Journal of Alloys and Compounds, 2014, 587: 544-552.
[20] BRACKE L, VERBEKEN K, KESTENS L, et al.Microstructure and texture evolution during cold rolling and annealing of a high Mn TWIP steel[J]. Acta Materialia, 2009, 57(5): 1512-1524.
[21] ZENG Z R, ZHU Y M, XU S W, et al.Texture evolution during static recrystallization of cold-rolled magnesium alloys[J]. Acta Materialia, 2016, 105: 479-494.
[22] THIRATHIPVIWAT P, ONUKI Y, UMEMURA K, et al.Microstructure, dislocation density and microhardness of 1% C-doped CoCrFeNi complex concentrated alloys during isochronal annealing[J]. Journal of Alloys and Compounds, 2023, 930: 167504.