基于弹塑性形变理论的拼焊板平面应力状态本构关系研究  

Research on constitutive relations of planar stress state of pieces-welded plate based on elastoplastic deformation theory

作　　者：孙东继[1] 林建平[1] 刘瑞同[1] 郭瑞泉[2] 倪锋[3] 阎启[2] 

机构地区：[1]同济大学机械工程学院,上海201804 [2]上海宝山钢铁股份有限公司,上海201900 [3]上海大众汽车有限公司,上海201805

出　　处：《机械设计》2009年第2期12-16,共5页Journal of Machine Design

基　　金：高等院校博士学科点专项科研基金资助项目(20070247025);上海汽车工业科技发展基金资助项目(0705)

摘　　要：从拼焊板成形过程4个基本理论假设出发建立其平面应力状态力学模型,根据金属板料弹塑性形变理论、Hill48屈服准则及金属塑性变形功原理导出拼焊板成形过程中厚、薄两侧母材应变分布状态相互依赖关系的隐式方程,并结合弹塑性理论的3个关系式建立了拼焊板在平面应力状态下的本构关系;采用通过实验验证的差厚拼焊板单向拉伸有限元模型分析了沿焊缝两侧母材的应力应变分布,且将仿真结果中厚板侧母材的两个面主应变分量作为前述本构关系已知条件,用数值方法求解出薄板侧母材的面内主应变与主应力分量,将其与相应仿真结果进行对比。对比结果表明,理论计算数值与仿真结果较为吻合,从而证明了拼焊板平面应力状态本构关系的正确性,为深入研究拼焊板冲压成形机理奠定了理论基础。Start from four basic theoretical hypotheses for the formation process of pieces-welded-plate, the mechanics model of its planar stress state was established. According to the elastoplastic deformation theory of metallic plate material, Hill48 yield criterion and principle of metallic plastic deformation, the implicit function for the mutual depending relationship of the strain distribution status on the two sides of the thick and thin base materials during the formation process of the pieces-welded-plate was derived, and combining with the three relationship formulae of the elastoplastic theory the constitutive relation under the planar stress state of pieces-welded-plate was established. By adopting the finite element model,which has been validated by test, for the unidirectional stretching of pieces-welded-plate with different thicknesses the stress-strain distribution of base materials along both sides of the welding seam was analyzed. Let the main strain component, obtained in the simulation result, on the two surfaces of the thick plate sided base material be regarded as the known condition of the previous stated constitutive relation, the components of principal strain and principal stress in the surface of the thin plate sided base material were solved. These components were contrasted with the corresponding simulation result ; the contrasted result indicated that the numerical-value of theoretical calculation tallies comparatively with the result of simulation. Thus the correctness of the constitutive relation of planar stress state of pieces-welded-plate was testified, and a theoretical foundation was laid for the deep study of press formation mechanism of pieces-welding-plate.

关 键 词：拼焊板 本构关系 平面应力状态 有限元 

分 类 号：TG386[金属学及工艺—金属压力加工]