| 大綱 |
摘要
板金成形的汽車結構件裡有些在設計上利用補強厚度來提高剛性以維持車體的結構安全，此法不僅會增加汽車的重量，補強厚度的材料及加工費用亦會提升汽車的成本，因此發展出了裁縫式鋼板的技術。
裁縫式鋼板係指以兩種或兩種以上的材料或不同厚度的鋼板拼焊而成，現今多數採用雷射拼焊，具備成本低精度高的特性，又可減輕車體重量，許多車廠跟進採用裁縫式鋼板的技術。
然而，兩種不同材料拼焊而成的鋼板具備兩邊材料特性不同的性質，在沖壓成形的過程中會面臨許多困難，如回彈量不同、容易破裂等等問題。本研究以有限元素法軟體進行模擬分析成形上的問題以及嘗試改善，以變壓料力、阻料條等方式消除側壁捲曲問題。此外，針對裁縫式鋼板上的焊道進行機械性質相關實驗，討論焊道在成形過程中以及CAE模擬上可能會有的影響。
關鍵字: 裁縫式鋼板、先進高強度鋼、回彈改善、CAE
Abstract
Due to the need of different
functions, make part of automobiles structures has to been
designed more thicker to reinforce the strength of the
automobiles body. This method will not only increase the
weight of automobiles, but also increase the cost of
processing and material. To overcome these problems,
Tailor-Welded Blank was then be invented.
Tailor-Welded Blank(TWB) means two or above kind of
materials being welded to become one blank. Now most of the
TWB is been welded by laser, which has feature of low
manufacturing cost and high accuracy, even more, TWB can be
designed flexibly to correspond function, which means only
use the specific material on the very need part of
automobiles structure, can reduce the usage of steel and
then reduce the weight of automobile. More and more
manufactory are using this technic.
However, TWB has two (or
above) kinds of material, which means it has two different
properties, in the progression of stamping will encounter
much of difficulties, such as two different springback and
fracture easily. This thesis aims at researching how to
overcome these problems based on CAE simulations. Variable
blank holder force and draw bead will be applied to
eliminate side curl. In addition, in order to discuss the
impact of weld line’s properties on metal forming and CAE
simulation, the experiment of weld line’s mechanical
properties will be verified.
Keywords:
Tailor-Welded Blank, Advanced High Strength Steel,
springback reduction, CAE
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