H.-M. Huang
,
J. Pan and S. C. Tang 1) Mechanical Engineering and Applied Mechanics
,
The University of Michigan Ann Arbor
,
MI 48109
,
USA 2) Ford Research Laboratory
,
Ford Motor Company Dearborn
,
MI 48121
,
USA
金属学报(英文版)
An approximate macroscopic yield criterion for anisotropic porous sheet metals is adopted in a failure prediction methodology that can be used to investigate the failure of sheet metals under forming operations. This failure prediction methodology is developed based on the Marciniak-Kuczynski approach by assuming a slightly higher void volume fraction inside randomly oriented imperfecte analysis. Here, a nonproportional deformation history including relative rotation of principal stretch directions is identified in a selected critical element of an aluminum sheet from a FEM fender forming simulation. Based on the failure prediction methodology, the failure of the critical sheet element is investigated under the non-proportional deformation history. The results show that thiven non-proportional deformation history.
关键词:
sheet metal forming
,
null
,
null
,
null
J.H.Yang
,
J.Chen
金属学报(英文版)
Due to complexities of draw-bead restraining force calculated according to theory and depending on sheet metal forming properties experiment testing system,a simplified method to calculate draw-bead restraining force is put forward by experimental method in cup-shaped drawing process. The experimental results were compared with numerical results and proved agreement. It shows the method is efective.
关键词:
sheet metal forming
,
null
,
null
L. H. Lang
,
D. C. Kang
,
S. H. Zhang
,
Z. R. Wang
,
S. J. Yuan
,
K. B. Nielsen and J. Dancket 1) Department of Materials Engineering
,
Harbin Institute of Technology
,
Harbin 150001
,
China 2) Aalberg University
,
Denmark
金属学报(英文版)
In this paper, the forming features of tapered rectangular box during hydrodynamic deep drawing are studied by means of FEM.The effect rules of square blank corner corner amount on body wrinkling are recognized and corresponding methods are discussed. At last, the results of FEM are verified by experi- ment.
关键词:
sheet metal forming
,
null
,
null
J.L. Song
,
D.J. Hu
,
Z.L. Chang
,
T.Y. Li
,
Z.B. Jiang
金属学报(英文版)
Based on the Finite Element Theory of Rigid Plastic, relevant problems during plastic simulation on sheet metal forming were technologically studied and simplified; a
simplified model of the blank holder during the drawing process was established and
the effects of related parameters on the forming processes were also studied. At the
same time, a finite-element numerical simulation program SPID was developed. The
distribution of strain and relationship of stress-stroke simulated were compared with
experimented, the results are well coincided with each other. It is verified that the
analytical program is reliable.
关键词:
sheet metal forming
,
null
,
null
李任君
,
李明哲
,
蔡中义
材料科学与工艺
采用曲面柔性轧制方法可以实现三维曲面板类件的连续、柔性成形，为了验证该方法的可行性，本文基于曲面柔性轧制原理，设计出成形装置并研究了装置关键部件工作辊的驱动方式，驱动方式可以分为单端与双端两种；进行相关成形实验并对曲面柔性轧制成形工艺进行了分析，探讨了成形过程。结果表明：一次调形成形工艺适用于小变形量情况，成形质量好，效率高；渐进调形成形工艺，以小的压下量逐渐使板料成形，在一定程度上可以消除板料边缘皱褶，减小回弹，利于板料成形；理论上讨论了实时调形成形工艺，该种工艺将会提高成形自动化与效率。对成形件进行了成形精度与厚度分布研究，表明成形效果良好，验证了曲面柔性轧制成形方法的可行性与实用性。
关键词:
板材成形
,
装置
,
三维曲面
,
柔性轧制
,
成形工艺
,
连续成形
,
多点成形
朱国明
,
康永林
,
吕超
机械工程材料
针对冷轧镀锌双相钢板，在完成U型梁冲压成形及回弹模拟分析的基础上，建立了闭口帽型梁的碰撞分析模型；采用映射的方法完成了U型梁的厚度、应力、应变向碰撞结构件的结果传递；在考虑冲压成形、回弹及应变速率等的情况下，对帽型梁的碰撞过程进行了模拟分析。结果表明：在碰撞过程中，由于应变速率较高，它的影响最为明显，在模型的定义过程中需要着重考虑；因为金属变形过程的加工硬化和厚度减薄等因素的影响，冲压结果直接影响碰撞过程的模拟结果；冲压后因回弹使零件内部的应力得到释放，残余应力减小，因此导致碰撞过程中产生相同的变形需要更大的外力，考虑回弹的刚性墙反力要比没有考虑时的高。
关键词:
模拟
,
双相钢
,
板材成形
,
应变速率
,
碰撞
