拉扭复合加载下循环应力应变关系的研究

Study on Cyclic Stress Strain Relation Under Tension Torsion Complex Loading

以拉扭薄壁管试件为研究对象，根据多轴临界面上的应力应变特性及多轴疲劳临界面法的研究结果，结合单轴循环应力应变关系，研究了多轴比例与非比例加载下的循环应力应变关系，推导出多轴循环应力应变关系模型，经拉扭复合比例与非比例循环加载试验验证。

In this paper, the tension torsion specimens were used as researching subjects. The cyclic stress strain relation under multiaxial proportional and nonproportional loading was studied according to the characteristic of the stress and strain on the multiaxial critical plane and the researching results of multiaxial critical plane principle. A multiaxial cyclic constitutive relation model under proportional loading was first derived based on the uniaxial cyclic stress strain relation, and then a multiaxial cyclic constitutive relation under nonproportional loading was obtained by the varying behaviour of the normal strain and the maximum shear strain on the critical plane. The experiments of tension torsion proportional and nonproportional cyclic loading were conducted to verify the model. The prediction of the model agrees with the experimental results reasonably well.