温度梯度下薄壁圆管试件拉伸性能的试验与理论研究

Experiment and Theory Investigation on Tension Behavior of Thin-walled Cylindrical Specimen at Temperature Gradient

开发了一个温度梯度试验系统,在不同温度以及温度梯度下对薄壁圆管试件进行拉伸试验。采用有限元软件模拟得到不同温度下材料的真实应力应变关系,采用计算流体软件对冷却薄壁圆管试件进行流固耦合传热分析,并将得到的温度载荷通过温度插值程序传递到有限元模型中。根据拟合得到的不同温度的材料性能,模拟温度梯度下拉伸过程,模拟结果与试验结果相吻合,结果表明:在目前的温度梯度下,温度梯度对材料的拉伸性能有一定的影响,但影响较小,可以采用通用的数值方法研究存在温度梯度的拉伸性能。

The test system at high temperature gradient was developed, and thin-walled cylindrical specimen was designed to carry out tension test at different temperatures and different temperature gradient. Practical method combined with finite element analysis to determinate the relation between stress and strain was developed. Distributions of temperature in specimen were obtained from coupled analysis of flow field and solid, and the temperature was transferred to FEM model by interpolation code. Based on the relation between true stress and true strain at different temperatures, the FEM simulation was carried out at temperature gradient. The result shows that the present temperature gradient has little influence on the tension behavior of specimen. And in this cose it is suitable to investigate the tension behavior of specimen with the usual numerical method.