ZrO2(Y2O3)含量对双峰晶粒度分布Mo-12Si-8.5B-ZrO2(Y2O3)复合材料力学性能的影响
doi: 10.13801/j.cnki.fhclxb.20210129.002
Effect of ZrO2(Y2O3) content on mechanical properties of Mo-12Si-8.5B-ZrO2(Y2O3) composites with bimodal grain-size distribution
-
摘要: 多相Mo-12Si-8.5B合金是一种很有应用前景的高温结构材料,为了同时提高Mo-12Si-8.5B合金的强度和韧性,提出了采用纳米ZrO2(Y2O3)强韧化具有双峰晶粒度分布Mo-12Si-8.5B复合材料的方法。首先采用溶胶-凝胶和高温氢还原法制备了纳米Mo-ZrO2(Y2O3)复合粉末,然后以纳米Mo-ZrO2(Y2O3)粉末和微米Mo粉末为原材料,采用放电等离子烧结(SPS)技术制备了具有双峰晶粒度分布的Mo-12Si-8.5B-ZrO2(Y2O3)复合材料。结果表明,随着ZrO2(Y2O3)含量的增加,制备的Mo-ZrO2(Y2O3)纳米粉末的粒度和烧结体相对致密度均逐渐减小,ZrO2(Y2O3)含量小于2.5wt%时,烧结体的相对致密度均大于98.1%。当ZrO2(Y2O3)含量为1.5wt%和2.5wt%时,复合材料具有较高的硬度(9.76~9.98 GPa),抗弯强度(672~678 MPa)和断裂韧性(12.68~12.82 MPa·m1/2)。Mo-12Si-8.5B-ZrO2(Y2O3)复合材料中Mo晶粒细化、粗细Mo晶粒的晶界强化和纳米ZrO2(Y2O3)颗粒第二相强化是提高硬度和抗弯强度主要原因;复合材料中粗晶粒Mo和纳米ZrO2(Y2O3)有助于断裂韧性的提高,材料的增韧机制主要是裂纹偏转和裂纹桥接。
-
关键词:
- Mo-12Si-8.5B /
- ZrO2(Y2O3) /
- 双峰晶粒度 /
- 力学性能 /
- 复合材料
Abstract: Multiphase Mo-12Si-8.5B alloy is a promising high-temperature structural material. In order to further simultaneously improve the strength and toughness of the Mo-12Si-8.5B alloy, the method of strengthening and toughening the bimodal grain size Mo-12Si-8.5B alloy with adding nano-ZrO2 (Y2O3) particles was put out. Nanometer Mo-ZrO2 (Y2O3) composite powders were successfully prepared by sol-gel and high-temperature hydrogen reduction method, and a series of Mo-12Si-8.5B-ZrO2 (Y2O3) composites with a bimodal grain size distribution were fabricated via spark plasma sintering (SPS) using nanometer Mo-ZrO2 (Y2O3) and micrometer Mo powders as raw materials. The results show that the particle size of Mo powders and the relative density of the sintered body decrease with the increase of the ZrO2 (Y2O3) content. When the ZrO2 (Y2O3) content is less than 2.5wt%, the relative density is above 98.1%. As the content of ZrO2 (Y2O3) are 1.5wt% and 2.5wt%, the composites exhibit the high hardness (9.76-9.98 GPa), flexural strength (672-678 MPa) and fracture toughness (12.68-12.82 MPa·m1/2). Grain refinement of the Mo, grain boundary strengthening of the nanometer/micrometer Mo grains and the second-phase strengthening of the nano-ZrO2(Y2O3) particles attribute to the increase of the hardness and flexural strength. The coarse grain Mo and nanometer ZrO2 (Y2O3) in the composites contribute to the improvement of the fracture toughness. The toughening mechanisms of the Mo-12Si-8.5B-ZrO2 (Y2O3) composites are crack deflection and crack bridging.-
Key words:
- Mo-12Si-8.5B /
- ZrO2(Y2O3) /
- bimodal grain size /
- mechanical properties /
- composites
-
图 4 烧结后Mo-12Si-8.5B-ZrO2(Y2O3)复合材料的微观组织
Figure 4. Microstructures of the Mo-12Si-8.5B-ZrO2(Y2O3) composites after sintering((a) Mo-12Si-8.5B-0wt%ZrO2(Y2O3); (b) Mo-12Si-8.5B-1.5wt%ZrO2(Y2O3); (c) TEM image of Mo-12Si-8.5B-1.5wt%ZrO2(Y2O3); (d) EDS spectra of spherical particles in Fig.4(c))
表 1 Mo-12Si-8.5B-ZrO2(Y2O3)复合材料所需Mo-ZrO2(Y2O3)粉末
Table 1. Mo-ZrO2 (Y2O3) powders required in the Mo-12Si-8.5B-ZrO2 (Y2O3) composites
Specimen Composition of Mo-ZrO2(Y2O3) powders Mo-12Si-8.5B Mo-0wt%ZrO2(Y2O3) Mo-12Si-8.5B-0.5wt% ZrO2(Y2O3) Mo-1.75wt%ZrO2(Y2O3) Mo-12Si-8.5B-1.5wt% ZrO2(Y2O3) Mo-5.0wt%ZrO2(Y2O3) Mo-12Si-8.5B-2.5wt% ZrO2(Y2O3) Mo-8.2wt%ZrO2(Y2O3) Mo-12Si-8.5B-5wt% ZrO2(Y2O3) Mo-15.6wt%ZrO2(Y2O3) Mo-12Si-8.5B-10wt% ZrO2(Y2O3) Mo-28.0wt%ZrO2(Y2O3) -
[1] LIU L, SHI C, ZHANG C, et al. Microstructure, microhardness and oxidation behavior of Mo-Si-B alloys in the Moss+Mo2B+Mo5SiB2 three phase region[J]. Intermetallics,2020,116:106618. doi: 10.1016/j.intermet.2019.106618 [2] LI R, LI B, CHEN X, et al. Variation of phase composition of Mo-Si-B alloys induced by boron and their mechanical properties and oxidation resistance[J]. Materials Science and Engineering: A,2019,749:196-209. doi: 10.1016/j.msea.2019.02.008 [3] CHOE H, CHEN D, SCHNEIBEL J H, et al. Ambient to high temperature fracture toughness and fatigue-crack propagation behavior in a Mo-12Si-8.5B (at. %) intermetallic[J]. Intermetallics,2001,9(4):319-329. doi: 10.1016/S0966-9795(01)00008-5 [4] ZHANG G J, DANG Q, KOU H, et al. Microstructure and mechanical properties of lanthanum oxide-doped Mo-12Si-8.5B(at%) alloys[J]. Journal of Alloys and Compounds, 2013, 15: S493-S498. [5] KRÜGER M, FRANZ S, SAAGE H, et al. Mechanically alloyed Mo-Si-B alloys with a continuous α-Mo matrix and improved mechanical properties[J]. Intermetallics,2008,16(7):933-941. doi: 10.1016/j.intermet.2008.04.015 [6] LI B, ZHANG G J, JIANG F, et al. Characterization of Mo-Si-B nanocomposite powders produced using mechanical alloying and powder heat treatment[J]. Journal of Materials Science& Technology,2015,31(10):995-1000. [7] LI B, ZHANG G J, JIANG F, et al. Preparation of fine-grained Mo-12Si-8.5B alloys with improved mechanical properties via a mechanical alloying process[J]. Journal of Alloys and Compounds,2014,609:80-85. doi: 10.1016/j.jallcom.2014.04.141 [8] WANG J, REN S, LI R, et al. Microstructure and improved mechanical properties of ultrafine-grained Mo-12Si-8.5B (at. %) alloys with addition of ZrB2[J]. Progress in Natural Science: Materials International,2018,28(3):371-377. doi: 10.1016/j.pnsc.2018.04.004 [9] MAJUMDAR S, KUMAR A, SCHLIEPHAKE D, et al. Microstructural and micro-mechanical properties of Mo-Si-B alloyed with Y and La[J]. Materials Science and Engineering: A,2013,573:257-263. doi: 10.1016/j.msea.2013.02.053 [10] LI W H, ZHANG G J, WANG S X, et al. Ductility of Mo-12Si-8.5B alloys doped with lanthanum oxide by the liquid-liquid doping method[J]. Journal of Alloys and Compounds,2015,642:34-39. doi: 10.1016/j.jallcom.2015.04.047 [11] LI R, LI B, WANG T, et al. Improved fracture toughness of a Mo-12Si-8.5B-3Zr alloy by grain coarsening and its multiple toughening mechanisms[J]. Journal of Alloys and Compounds,2018,743:716-727. doi: 10.1016/j.jallcom.2018.01.398 [12] YAN J H, WANG Y, ZHOU P, et al. Microstructures and room temperature mechanical properties of Mo-12Si-8.5B-8Cr alloy[J]. Transactions of the Indian Institute of Metals,2018,71(1):245-251. doi: 10.1007/s12666-017-1173-z [13] ZHA M, ZHANG H M, YU Z Y, et al. Bimodal microstructure-A feasible strategy for high-strength and ductile metallic materials[J]. Journal of Materials Science & Technology,2018,34(2):257-264. [14] BUI Q H. Heterogeneous plastic deformation in bimodal bulk ultrafine-grained nickel[J]. Journal of Materials Science,2012,47(4):1902-1909. doi: 10.1007/s10853-011-5979-5 [15] FAN G J, CHOO H, LIAW P K, et al. Plastic deformation and fracture of ultrafine-grained Al-Mg alloys with a bimodal grain size distribution[J]. Acta Materialia,2006,54(7):1759-1766. doi: 10.1016/j.actamat.2005.11.044 [16] WANG Y M, CHEN M W, ZHOU F H, et al. High tensile ductility in a nanostructured metal[J]. Nature,2002,419(6910):912-915. doi: 10.1038/nature01133 [17] LI R, LI B, CHEN X, et al. Enhanced fracture toughness and toughening mechanisms of fine-grained Mo-12Si-8.5B alloy with a bi-modally structured α-Mo grain[J]. Materials Science & Engineering:A,2020,772:138684. [18] CUI C P, ZHU X G, LIU S L, et al. Effect of nano-sized ZrO2 on high temperature performance of Mo-ZrO2 alloy[J]. Journal of Alloys and Compounds,2018,768:81-87. doi: 10.1016/j.jallcom.2018.07.214 [19] 康蓉, 颜建辉, 李茂键. 溶胶凝胶/高温氢还原法制备纳米Mo-ZrO2(Y2O3)复合粉末[J]. 稀有金属, 2021, 45(3): 288-296.KANG R, YAN J H, LI M J. Preparation of nanometer Mo-ZrO2(Y2O3) composite powder by sol-gel and high temperature hydrogen reduction[J]. Chinese Journal of Rare Metals, 2021, 45(3): 288-296(in Chinese). [20] LI Z, XU L J, WEI S H, et al. Fabrication and mechanical properties of tungsten alloys reinforced with c-ZrO2 particles[J]. Journal of Alloys and Compounds,2018,769:694-705. doi: 10.1016/j.jallcom.2018.07.342 [21] GHADERI HAMIDI A, ARABI H, VAHDATI KHAKI J. Sintering of a nano-crystalline tungsten heavy alloy powder[J]. International Journal of Refractory Metals & Hard Materials,2019,80:204-209. [22] SCHNEIBEL J H, TORTORELLI P F, RITCHIE R O, et al. Optimization of Mo-Si-B intermetallics[J]. Metallurgical & Materials Transactions A,2005,36:525-531. [23] 徐健建, 颜建辉, 汪异, 等. W对Mo-Si-B合金微观组织和力学性能的影响[J]. 材料热处理学报, 2015, 36(8):22-27.XU J J, YAN J H, WANG Y, et al. Effect of W addition on microstructure and mechanical properties of Mo-Si-B alloy[J]. Transactions of Materials and Heat Treatment,2015,36(8):22-27(in Chinese). [24] LI R, ZHANG G J, LI B, et al. The multi-scale microstructure and strengthening mechanisms of Mo-12Si-8.5BxZr (at. %) alloys[J]. International Journal of Refractory Metals and Hard Materials November. 2017, 68: 65-74. [25] WU X L, ZHU Y T. Heterogeneous materials: A new class of materials with unprecedented mechanical properties[J]. Materials Research Letters,2017,5(8):527-532. doi: 10.1080/21663831.2017.1343208 [26] ASHBY M F, BLUNT F J, BANNISTER M K. Flow characteristics of highly constrained metal wires[J]. Acta Metallurgica,1989,37(7):1847-1857. doi: 10.1016/0001-6160(89)90069-2 [27] LU G Y, LEDERICH R, SOBOYEJO W. Residual stresses and transformation toughening in MoSi2 composites reinforced with partially stabilized zirconia[J]. Materials Science and Engineering: A,1996,210(1-2):25-41. doi: 10.1016/0921-5093(95)10075-X