【摘要】 为了研究非轴对称旋压的成形机理,并为以后的参数优化及工艺设计提供依据,采用有限元分析MSC.MARC软件,基于三维弹塑性有限元理论建立有限元模型,对倾斜类管件的旋压成形过程进行了数值模拟.分析得出了单道次旋压成形时的金属流动特点及应力、应变分布规律,并预测了成形过程中可能出现的缺陷及其区域.模拟和工艺试验结果表明:倾斜使得旋压件的变形网格、应力场、应变场、壁厚分布都呈非轴对称分布,旋压件的三向主应力、应变在圆周方向大致呈正弦或余弦分布;成形时毛坯向0°域倾斜,该区域的起旋点附近具有较严重的壁厚减薄现象,是倾斜类管件旋压成形时较容易发生破裂缺陷的区域.更多还原

【Abstract】 In order to investigate the mechanism of non-axisymmetric spinning and provide accordance for the corresponding parameter optimization and process design,a finite-element analytical(FEA) model is established based on the 3D elastic-plastic theory to numerically simulate the neck-spinning process of oblique tubes by the FEA MSC.MARC software.The characteristics of metal flow and the distributions of the stress and the strain in the one-path spinning are then obtained,and the potential defects and defect areas in the spinning are forecasted.Both the simulative and the experimental results show that the distributions of the deformed mesh,the stress,the strain and the thickness of the workpiece are all asymmetric due to the oblique spinning,that the distributions of the principal stresses and strains in the circumferential direction are sinusoidal or cosinoidal functions,and that,in the spinning,severe thinning occurs near the initial spinning area due to the leaning of workpiece towards the zero region,that is,the dangerous region where breaking may occur.更多还原