基于多位错塞积理论,建立了全片层γ-TiAl基合金屈服强度尺度效应的解析预测细观力学模型,得到了全片层γ-TiAl基合金屈服强度的计算公式并详细分析了晶粒尺寸d和片层厚度λ对屈服强度的影响关系,数值预测结果趋势与已有的试验结果相吻合.主要结论是:γ-TiAl基合金屈服强度对晶粒大小d变化不敏感,而对片层厚度λ具有强烈的依赖关系,随着片层厚度的减小,屈服强度明显增大,表现出显著的尺度效应;屈服强度与片层厚度之间的制约关系在一定的片层尺度范围内符合Hall-Petch关系.值得注意的是,当片层尺寸λ细化至90nm时,γ-TiAl基合金材料的屈服强度达到一极限饱和值,这一极限饱和值约为1000MPa.
参考文献
| [1] | R. Cao;Y.Z. Lin;D. Hu .Fracture behaviour of a TiAl alloy under various loading modes[J].Engineering Fracture Mechanics,2008(15):4343-4362. |
| [2] | Werwer M;Cornec A .The role of superdislocations for modeling plastic deformation of lamellar TiAl[J].International Journal of Plasticity,2006(9):1683-1698. |
| [3] | Yu-Lung Chiu;Patrick Veyssi`ere.Dislocation self-organization under single slip straining and dipole properties[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2008:191-194. |
| [4] | J. Chraponski .The effect of lamellar separation on the properties of a Ti-46Al-2Nb-2Cr intermetallic alloy[J].Materials Characterization,2006(4/5):414-420. |
| [5] | 李臻熙,段锐,曹春晓.γ-TiAl合金全片层组织室温变形协调行为[J].中国有色金属学报,2008(02):203-208. |
| [6] | 丛韬,黄泽文.长期大气热暴露环境中含钨铌TiAl合金的组织和性能变化[J].航空材料学报,2008(03):5-11. |
| [7] | Sun YQ. .An extended dislocation pile-up model for the yield strength of lamellar microstructures[J].Philosophical Magazine.A.Physics of condensed matter, defects and mechanical properties,1998(4):1107-1126. |
| [8] | SUN Y Q .Strengthening of fully-lamellar TiAl:a dislocation pileup analysis[J].Materials Science and Engineering A:Structural Materials Properties Microstructure and Processing,1997,239-240:131-146. |
| [9] | Maruyama K.;Suzuki G.;Kim HY.;Suzuki M.;Sato H. .Saturation of yield stress and embrittlement in fine lamellar TiAl alloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2002(0):190-195. |
| [10] | MARUYAMA K;YAMADA N;SATO H .Effects of lamellar spacing on mechanical properties of fully lamellar Ti 39.4mol% Al alloy[J].Materials Science and Engineering A:Structural Materials Properties Microstructure and Processing,2001,319-321:360-363. |
| [11] | DIMIDUK D M;HAZZLEDINE P M;PARTHASARATHY T A .The role of grain size and selected microstructure parameters in strengthening fully lamellar TiAl alloy[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1998,27:37-47. |
| [12] | 苏继龙,胡更开.近片层γ-TiAl基合金宏观塑性行为的尺度效应[J].中国有色金属学报,2006(10):1684-1688. |
| [13] | 哈宽富.金属力学性质的微观理论[M].北京:科学出版社,1991 |
| [14] | 曹国鑫,林建国,孙志鹏,张永刚,陈昌麒.晶粒尺度和片层厚度对全片层γ-TiAl合金性能的影响[J].稀有金属材料与工程,2000(03):172-176. |
| [15] | 付连峰,林建国,曹国鑫,张永刚,陈昌麒,清华大学,北京.全片层TiAl基合金的屈服强度与显微组织关系[J].稀有金属材料与工程,2001(03):178-182. |
| [16] | ZHU Han-liang;SEO D Y;MARUYAMA K et al.Effect of lamellar spacing on microstructural instability and creep behavior of a lamellar TiAl alloy[J].Scripia Materialia,2006,54:1979-1984. |
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