汽車葉子板輪罩之沖壓成形與折邊分析

An Analysis of Stamping Process for the Fender-Wheel Side of Automobile

曾慶豪(Chin-Hao Tseng)

指導教授 ： 許源泉

國立虎尾科技大學/工程學院/創意工程與精密科技研究所在職專班/碩士(2012年)

https://doi.org/10.6827/NFU.2012.00091

摘要

本研究結合有限元素模擬軟體與沖模設計理論，探討車身葉子板輪罩處使用不同的造形，對傳統工站模具的冷沖壓成形之影響。在引伸成形分析上，探討車身葉子板在輪罩的折邊處造形對成形能力之影響；在沖剪成形分析上，則是探討模具間隙與壓料壓力對沖剪斷面之影響；在彎曲成形分析上，則是探討模具間隙、壓料壓力以及沖彎速度對於板材折彎成形性之影響；透過有限元素分析軟體對引伸、沖剪、彎曲與整形行為進行分析，並驗證CAE模擬板材成形之正確性。
本研究透過板材拉伸試驗建構出B180H板材性質完整的資料庫。經由研究結果顯示，在板材引伸方面，可利用過抽、預彎及雨滴造形來做折彎前的料厚補償；補償必須適宜，若過多可能造成過積料，過少則會發生料厚不足現象；在沖剪方面，當模具間隙越小時，模輥面與撕裂面尺寸值越小，而剪切面尺寸則會越大；當壓料壓力越大時，模輥面與撕裂面尺寸值越小，而剪切面尺寸則會越大，依此理論探討過抽及雨滴造形對剪線的影響。在板材彎曲方面，影響尺寸精度及回彈量之主要參數為模具間隙與壓料壓力；影響板材應變之主要參數為模具間隙與沖彎速度，依此原理探討過抽及雨滴造形對折彎面的影響。

關鍵字

葉子板 ； 工站模具 ； 雨滴 ； 沖壓成形

並列摘要

This paper is aimed to study different aspects of stamping tool design for the sheet metal parts and to study the physics theories to be considered in stamping tool design. Fender, as one of the most critical sheet metal part in a vehicle, will be used as a sample for studying different topics.

This paper will also show a complete database of the property of BH180H sheet metal material after conducting a research of load-elongation trials on the BH180H sheet metal. The result of this research proves that over-drawing method, pre-bending method, and rain-drop emboss can be utilized in the drawing operation to compensate the problem of insufficient material. However, such compensation needs to be properly calculated to avoid too much excessive material or insufficient material.
Regarding to the trimming operation, when the gap between two blades is reduced, the length of rollover plane and fracture plane will become shorter but the length of the burnish plane will become longer. When the force of the pressure pad is increased, the length of rollover plane and fracture plane will become shorter but the length of the burnish plane will become longer. The result of above mentioned research can be used to discuss how trim line is affected by over-drawing and rain-drop emboss. As for bending operation, the major factors contributing to the spring-back effect and the residual-strength effect of the sheet metal after bending are the gap between two bending blocks and the speed of bending process. Based on this theory, the effect of over-drawing and rain-drop emboss on bending surface can be inferred.

並列關鍵字

fender ； line die ； rain-drop ； stamping

參考文獻

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