螺栓结合面的三维弹塑性接触的有限元分析

Finite Element Analysis of Three-dimensional Elastic-plastic Contact Model for Bolted-joint Interfaces

为揭示螺栓结合面的微观接触机理,探究不同加载下三维表面粗糙度参数的变化,基于实测的三维形貌数据,建立了螺栓结合面的三维弹塑性有限元接触模型;进一步通过提取有限元模型表面节点坐标及其变形量,重构受压后的三维形貌。测得的表面粗糙度峰值高度明显降低,其三维粗糙度参数S_(a)、S_(q)、S_(p)、S_(v)和S_(z)随着装配载荷的增加而逐渐降低,粗糙表面接触面积逐渐增加。最大的Von Mises应力发生在表面轮廓的波峰处。数值算例的结果表明,建立的数值模型反映了螺栓结合面真实的三维形貌,具有较高的建模精度,实现了装夹塑性变形后粗糙表面三维形貌的预测。

In order to reveal the microscopic contact mechanism of the bolted-joint interfaces and investigate the change of three-dimensional surface roughness parameters under different loads, based on the measured three-dimensional morphology data, a three-dimensional elastic-plastic finite element contact model for bolted-joint interfaces was established and moreover, the 3 D morphology was reconstructed by extracting the node coordinates of the finite element model and their deformations caused by the clamping force.The height of surface roughness decreased obviously.With the increase of load, three-dimensional surface roughness parameters S_(a)、S_(q)、S_(p)、S_(v)and S_(z)decreased, and the contact area of rough surface increased gradually.The maximum Von Mises stress occurred at the crest of the surface profile.The results of numerical examples showed that the established numerical model reflected the real three-dimensional morphology of the bolt joint interface, and had high modeling accuracy, which can realize the prediction of three-dimensional morphology of the rough surface after clamping plastic deformation.