Deformation Characteristics and Press-Formability of Steel/Aluminium Clad Sheet Metals

钢/铝复合板材的变形特性和冲压成形性

• 批准号: 04650088
• 负责人: YOSHIDA Fusahito
• 金额: $ 1.34万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650088/
• 关键词: Stainless-Steel Clad Aluminium Sheet Metals; Press-Formability; Forming Limit; Localized Necking; Stretch Bending; Unbending; Sheet-Thickness Change; Delamination; 引張り曲げ・曲げもどし; 鋼; アルミニウム系クラッド板; 引張り試験; 張出し試験; 引張り曲げ; 曲げもどし; くびれ発生条件; 成形限界線図 /

Deformation characteristics and press-formability in biaxial stretching and stretch bending/unbending were investigated for warn-roll-bounded (at 400ﾟC) two-ply (SUS430/A1) and three-ply (SUS430/A1/SUS304) clad sheet metals. Delamination during stretch bending/unbending was also discussed for cold-roll-bonded SUS304/A1 clad sheet metals. The results are summarized as follows.(1) The forming limit diagrams (FLD) for the clad sheet metals and their components (SUS304, SUS430 and A1) were experimentally determined. The clad sheet metals of SUS430/A1 and SUS430/A1/SUS304 have higher formability compared with the warn-rolled SUS430 sheet.(2) The forming limit in the positive strain ratio for clad sheet metals has been derived based on Hill's localized necking concept. The predicted FLD by the theory agrees comparativery well with the experimental one.(3) The forming limit in the negative strain ratio for clad sheet metals can be explained by a model of the progress of sheet-thickness imperfection with consideration of void growth (modified M-K theory + void growth).(4) The sheet-thickness change during stretch bending/unbending around a die corner was examined both experimentally and theoretically for the clad sheet metals. The effects of laminate geometry (clad ratio), a die radius and stretching force on the sheet-thickness change have been clarified.(5) Delamination during stretch bending/unbending around a die corner was investigated for a cold-roll-boned SUS430/A1 sheet. Delamination likely occurs when a die radius is smaller and the stretching force is larger. It was found from the numerical simulation of the stretch bending/unbending that the delamination is strongly affected by the normal and shear stresses acting on the laminate boundary of a clad sheet during unbending process.

研究了双辊结合(400ﾟC)、二层(SUS430/A1)和三层(SUS430/A1/SUS304)复合板材在双向拉伸和拉伸弯曲/未弯曲状态下的变形特征和冲压成形性能。还讨论了冷轧复合SUS304/A1复合板在拉伸弯曲/未弯曲过程中的分层问题。主要研究结果如下：(1)实验确定了复合板及其构件(SUS304、SUS430和A1)的成形极限图(FLD)。SUS430/A1和SUS430/A1/SUS304复合板材的成形性高于预轧的SUS430板材。(2)基于Hill的局域颈缩概念，推导了复合板材的正应变比成形极限。(3)考虑孔洞增长的板厚缺陷发展模型(修正的M-K理论+孔洞增长)可以解释复合板在负应变比下的成形极限。(4)从实验和理论两方面考察了复合板在模具拐角拉伸弯曲/展开过程中的板厚变化。研究了层合板几何形状(包覆率)、模具半径和拉伸力对板材厚度变化的影响。(5)研究了冷轧SUS430/A1板材在模具拐角拉伸弯曲/展开过程中的分层。当模具半径较小且拉伸力较大时，可能会发生分层。拉伸弯曲/未弯曲的数值模拟发现，复合材料层合板在未弯曲过程中，作用在层合板边界上的法向应力和剪应力对分层有很大的影响。

项目成果

F.Yoshida: "STRETCH BENDING AND THE SUBSEQUENT STRAIGHTENING OF SHEET METAL LAMINATES" Advances in Engineering Plasticity and its Applications. 1097-1104 (1993)

F.Yoshida：“金属层压板的拉伸弯曲和随后的矫直”工程塑性及其应用的进展。

F.Yoshida,R.Hino and T.Okada: "Stretch bending and the subsequent straightening of sheet metal laminates" Advances in Engineering Plasticity and Its Applications. 1097-1104 (1993)

F.Yoshida、R.Hino 和 T.Okada：“金属板层压板的拉伸弯曲和随后的矫直”工程塑性及其应用的进展。

Ryutaro HINO, Fusahito YOSHIDA and Tatsuo OKADA: "Biaxial Forming Limit for Stainless/Aluminium Laminates." Proceedings of '93-Spring Meeting of JSTP. Vol.1. 227-280 (1993)

Ryutaro HINO、Fusahito YOSHIDA 和 Tatsuo OKADA：“不锈钢/铝层压板的双轴成形极限”。

Ryutaro HINO, Fusahito YOSHIDA and Tatsuo OKADA: "Fracture of Stainless/Aluminium Sheet Laminates under Biaxial Stress Condition." Proceedings of 71st JSME Meeting. Vol.B. 293-295 (1993)

Ryutaro HINO、Fusahito YOSHIDA 和 Tatsuo OKADA：“双轴应力条件下不锈钢/铝板层压板的断裂”。

日野隆太郎: "ステンレス/アルミニウム積層板の成形限界" 日本塑性加工学会春季講演会論文集(平成6年度). (予定). (1994)

Ryutaro Hino：“不锈钢/铝层压板的成形极限”日本塑性加工学会春季会议论文集（1994 年）（计划）。