超塑性单向拉伸变形的数学模型及稳定性解析Mathematical model and stability analysis of superplastic tensile deformation in perfect condition
索忠林;
摘要(Abstract)：
超塑性变形的失稳是一个复杂的问题,多年来各国学者在失稳的力学研究方面做出很大的贡献,但是由于不同学者的研究思路和方法不同,所得的结论也各异,因此有必要在理论上进行规范。通过建立超塑性拉伸变形在均匀变形阶段的数学模型,从数学理论的角度出发解析变形的稳定性,从而得出应变硬化指数是变形是否稳定的关键参数的结论;并通过不同的变形路径对模型进行解析,从而得出拉伸试样在整体载荷达到最大后并不立刻出现局部的宏观颈缩,而是延迟一段时间后才出现局部的宏观颈缩的重要结论。
关键词(KeyWords)： 数学模型;失稳;载荷变化率;应力变化率
基金项目(Foundation):
作者(Author): 索忠林;
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DOI:
参考文献(References)：
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