Plastic deformation behavior of Ll_2 type intermetallic compound containing precipitate phase.

含析出相的Ll_2型金属间化合物的塑性变形行为

• 批准号: 62550525
• 负责人: SANO Takeshi
• 金额: $ 1.22万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62550525/
• 关键词: Nickel-aluminium-titanium alloy; Single crystal; Precipitation hardening; Coherency; Transmission electron microscopy; EDS microanalysis; Antiphase energy; ニックル-アルミニウム-チタン合金; 析出硬化; 塑性変形機構; APBエネルギー; 硬化モデル; 塑性変形挙動; 超格子転位

Optimum alloy compositions and heat treatments to obtain fine dispersion of disordered -particles in an Li_2 ordered '-Ni_3(Al,Ti), and the morphology change of precipitates during ageing have been investigated in terms of transmission electron microscopy. The ' phase hardens appreciably by the fine precipitation of disordered . The initial shape of precipitates formed during ageing is spherical or round-cubic and grow into platelets as ageing proceeds. High resolution electron microscopy revealed that the precipitates are perfectly coherent with the matrix ' as long as the -precipitates are plates. The chemical compositions of the martrix and the precipitates have been determined by using EDS microanalysis in an analytical electron microscope.Morphology of dislocations in deformed '-Ni_3(Al,Ti) single crystals containing fine dispersions of disordered -particles has been investigated in terms of weak beam dark field transmission electron microscopy. Superlattice dislocations dissociat … More e into fourfold shockley partial disloca-tions in a uniform supersaturated solid solution of ' phase and in the matrix. At any stage of ageing, dislocations cut through the particles and the Orowan bypassing process dose not occur in this alloy system.Strengthening mechanisms in an ordered intermetallic compound contaning coherent precipitates of lower antiphase boundary energy than the matrix have been investigated on the basis of observation of the interaction between deformation induced dislocations and disordered precipitates in an Ll_2 ordered Ni_3(Al,Ti). Extra work necessary to pulll out the dislocations from the precipitate is dependent on the difference of antiphase boundary energy between the matrix and the precipitatem the size and volume fraction of precipitate.Strength of '-Ni_3(Al,Ti) Ll_2 ordered phase containing fine precipitates of disordered phase have been examined on basing upon the proposed model. The model can explain almost quantitatively the age hardening behaviour of ordered Ni_3(Al,Ti) phase. Less

利用透射电子显微镜研究了在Li_2有序'-Ni_3（Al，Ti）中获得无序颗粒细分散的最佳合金成分和热处理工艺，以及时效过程中析出物的形态变化。该相通过无序相的精细沉淀而明显硬化。在时效过程中形成的沉淀物的初始形状是球形或圆立方体，并随着时效的进行而生长成片状。高分辨电子显微镜显示，只要沉淀物是板状的，沉淀物与基体是完全共格的。用分析电子显微镜的EDS微区分析确定了马氏体和沉淀相的化学成分，用弱束暗场透射电子显微镜研究了含有弥散无序颗粒的变形'-Ni_3（Al，Ti）单晶中位错的形貌。超晶格位错离解 ...更多信息 在均匀过饱和固溶体中和基体中，在时效的任何阶段，位错都能穿透颗粒而不发生Orowan绕过过程.本文在观察Ll_2有序Ni_3（Al，Ti）中形变诱导位错与无序析出相相互作用的基础上，研究了含有反相界面能低于基体的共格析出相的有序金属间化合物的强化机制.从析出相中拉出位错所需的额外功取决于基体与析出相之间的反相边界能差、析出相的尺寸和体积分数.在此基础上，研究了含有无序相的细小析出相的'-Ni_3（Al，Ti）Ll_2有序相的强度.该模型几乎可以定量地解释Ni_3（Al，Ti）有序相的时效硬化行为。少

项目成果

Tian Wen Huai: "Deformation induced microstructure of '-L1_2 ordered Ni_3(Al,Ti) SINGLE single crystals containing fine dispersion of disordered -precipitates" Journal of the Japan Institue of Metals.

田文怀：“含有无序沉淀物精细分散的‘-L1_2有序Ni_3(Al,Ti)单晶的变形诱导微观结构”，日本金属学会学报。

Tian Wen Huai: "Precipitation of disordered phase in a L1_2 ordered '-Ni_3(Al,Ti) phase" Journal of the Japan Institue of Metals.

田文怀：“L1_2有序-Ni_3(Al,Ti)相中无序相的沉淀”，日本金属学会学报。

Tian Wen Huai: "Hardening mechanisms in a ' L1_2 ordered phase containing disordered precipitates" Journal of the Japan Institue of Metals.

田文怀：“含有无序析出物的L1_2有序相的硬化机制”，日本金属学会学报。

田文懐: 日本金属学会誌.

田文凯：日本金属学会杂志。