γ-TiAl基合金弹性和塑性尺度效应所对应内在特征尺寸的关系

发布时间：2018-02-13 06:18

本文关键词： γ-TiAl基合金力学性能微极理论尺度效应　出处：《中国有色金属学报》2015年02期 　论文类型：期刊论文

【摘要】：将近片层γ-TiAl基合金视为以等轴γ颗粒为夹杂、多孪晶PST单晶组分为微极基体的复合材料,运用微极理论研究与其等效弹性性能尺度效应对应的材料特征尺度lm和塑性流动行为尺度效应对应的材料特征尺度lp之间的关联。结果表明:相对于硬相的PST组分基体,软相等轴γ颗粒夹杂直径d与微极基体的材料内在的弹性特征尺度lm和塑性特征尺度lp相当时,夹杂尺寸将对合金材料的等效弹性模量和塑性流动行为产生一定的影响;合金材料的弹性模量随着夹杂颗粒尺寸的减小而增大,夹杂颗粒越小,合金材料的塑性流动硬化特征越明显。γ-TiAl基合金中与弹性性能尺度相对应的材料特征尺度lm与塑性行为尺度效应所对应的内在材料特征尺度lp相等,并与γ-Al合金复合材料基体组分中PST颗粒的尺寸大小一致。
[Abstract]:The near lamellar 纬 -TiAl-based alloy is regarded as a composite composed of equiaxed 纬 particles and multi-twin PST single crystal as micropolar matrix. The correlation between the material characteristic scale (LM) corresponding to the scale effect of equivalent elastic properties and the material characteristic scale (LP) corresponding to the scale effect of plastic flow behavior is studied by using the micropolar theory. The results show that the matrix of the PST component is relative to the hard phase. When the inclusion diameter d of the soft equal axis 纬 particle is equivalent to the intrinsic elastic characteristic scale (LM) and the plastic characteristic scale (LP) of the micropolar matrix, the inclusion size will have a certain effect on the equivalent elastic modulus and plastic flow behavior of the alloy material. The elastic modulus of the alloy increases with the decrease of the size of the inclusions, and the smaller the inclusions are, The more obvious the plastic flow hardening is, the more obvious is the intrinsic material characteristic scale (LP) corresponding to the elastic property scale in 纬 -TiAl-based alloy, and the intrinsic material characteristic scale L _ p corresponding to the plastic behavior scale effect in 纬 -TiAl-based alloy. The size of PST particles in the matrix of 纬 -Al alloy composites is the same as that of 纬 -Al alloy composites.
【作者单位】：福建农林大学机电工程学院;
【基金】：国家自然科学基金资助项目(10972056) 福建省百千万人才工程人选海外研修项目(闽人复[2013]1号)
【分类号】：TG146.23

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