材料参数对拉伸失稳影响的力学解析  

MECHANICAL ANALYSIS OF TENSILE INSTABILITY DUE TO MATERIAL PARAMETER

作　　者：宋玉泉[1] 索忠林[1] 管志平[1] 刘颖[1] 

机构地区：[1]吉林大学超塑性与塑性研究所,长春130025

出　　处：《金属学报》2006年第4期337-340,共4页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目50375064;吉林大学"985工程"项目资助

摘　　要：超塑性变形的失稳比塑性变形失稳复杂得多,国内外学者在失稳的力学研究方面已发表了许多有价值的论文,对超塑性研究的进展贡献很大．由于不同学者的研究思路和研究方法不同,所得的结论也各异,因此有必要进行理论规范．本文从变形的状态方程出发,对无几何缺陷试样在恒温条件下仅由材料本身所产生的拉伸失稳进行力学理论解析,旨在研究材料力学参数对失稳的影响．所得结果不仅与一些典型论文的失稳判据完全一致,而且从理论上论证了超塑性拉伸变形在载荷失稳时不发生几何失稳,而是要经历一段均匀变形后才出现几何失稳．Instabilities during superplastic deformation is more complicated than those during plastic deformation. Many valuable papers about mechanical analysis of instability have been published at home and abroad, which contributed much to the development of superplastic research. But their conclusions were different because of the diversity of the researchers＇ thoughts and methods. Therefore, it is necessary to normalize these theories. In order to study the impact of material＇s mechanical parameter on instability, a criterion of the tensile instability of specimen without geometric defect at constant temperature, which is induced only by material parameter, was analyzed based on state equation of deformation in this paper. The results not only coincided with those in some typical papers, but also proved theoretically that the geometrical instability during superplastic deformation will happen after a period of uniform deformation under load instability, rather than in the meantime of load instability.

关 键 词：超塑性 无几何缺陷试样 恒温 拉伸失稳判据 

分 类 号：TG113.25[金属学及工艺—物理冶金]