单层厚壁圆筒的自增强损伤研究

Study on the Autofreetage Damage Mechanism of Monolayer Thick-wall Columnars

用损伤变量研究自增强厚壁圆筒产生自增强的过程,引入损伤有效应力的概念,结合自增强厚壁圆筒的结构特点,建立了单层厚壁圆筒的损伤自增强模型。给出了损伤区和弹性区的应力表达式、损伤自增强压力、外壁环向应变与损伤自增强残余应力等表达式。借助于25Cr2MoV材料的自增强实验数据对损伤自增强模型进行了测算,结果表明,损伤自增强模型与理想弹塑性模型、双线性硬化模型相比更接近于实测值。重要意义在于可能产生新的单层厚壁圆筒的研究方向。

The autofrettage theoretical deduction process was studied with the damage variables. By introducing the effective damage stress, and combining the characterics of the autofrettage thick-wall columnar, the autofrettage damage mechanics model was set up. The relationship between autofrettage stress, critial damage press, critial damage radius, outer-wall annular strain, and autofrettage residual stress for damage and elastic zones were also given. The results indicate that the autofrettage mechanics model is validate for 25Cr2MoV. Comparision with the idel elastic-plastic model and the two-way linear hardness model, the autofrettage damage model is more aprroach to the experiments. The significant of the model may open a new research direction for monalayer thick-wall columnars.