發(fā)布時間：2019-07-06 17:53

【摘要】：面對環(huán)境污染、能源短缺等一系列問題,實(shí)現(xiàn)汽車輕量化成為汽車行業(yè)發(fā)展的必然趨勢。由于采用拼焊板沖壓成形的零件裝配汽車,能在很大程度上減輕車重,降低生產(chǎn)成本,因此拼焊板沖壓成形技術(shù)在汽車行業(yè)中的應(yīng)用越來越廣泛。拼焊板在彎曲成形過程中由于板厚的差異、材料的差異、焊縫及其熱影響區(qū)等因素的影響會產(chǎn)生焊縫移動、回彈等缺陷,這些缺陷嚴(yán)重影響彎曲件的尺寸精度,降低產(chǎn)品質(zhì)量,因此對拼焊板彎曲成形過程中的焊縫移動和回彈進(jìn)行研究具有重要的意義。在拼焊板彎曲件中,以帽形件最為典型,為有效控制拼焊板帽形件在彎曲成形過程中的焊縫移動和回彈問題,本文以橫向拼焊板帽形件和縱向拼焊板帽形件為研究對象,首先建立了各自的有限元模型,并利用有限元軟件DYNAFORM對其彎曲成形過程以及卸載后的回彈過程進(jìn)行數(shù)值模擬,主要分析了壓邊力、摩擦系數(shù)、凸模圓角半徑、凹模圓角半徑、料厚比對焊縫移動和回彈的影響。此外對焊縫不在中間位置的橫、縱向拼焊板帽形件(焊縫偏向薄側(cè)或偏向厚側(cè))進(jìn)行了研究,得到了壓邊力、料厚比和焊縫位置對其彎曲成形的影響。本文對壓邊力進(jìn)行了詳細(xì)的研究,研究了薄厚側(cè)不同組合的恒壓邊力對焊縫移動和回彈的影響,在此基礎(chǔ)上研究了變壓邊力中初始壓邊力、壓邊力隨凸模行程變化點(diǎn)以及高壓邊力對焊縫移動和回彈的影響�；谝陨涎芯�,針對橫、縱向拼焊板帽形件和橫、縱向非對稱拼焊板帽形件的彎曲成形,提出了可以有效減小焊縫移動和回彈的方法:成形初期施加較小且合理的薄厚側(cè)壓邊力組合,保證焊縫移動較小,當(dāng)凸模行程接近總的彎曲行程時,同時增大薄厚側(cè)壓邊力,使回彈減小。
文內(nèi)圖片：
圖片說明：轎車車體結(jié)構(gòu)中拼焊板的使用情況
[Abstract]:In the face of a series of problems, such as environmental pollution, energy shortage and so on, the realization of automobile lightweight has become an inevitable trend in the development of automobile industry. Because the assembly of parts with welded plate can reduce the weight of the car and reduce the production cost to a great extent, the stamping technology of welded plate is more and more widely used in the automobile industry. Due to the difference of plate thickness, material, weld and its heat affected zone, the defects such as weld movement and springback will occur in the bending process of welded plate. These defects seriously affect the dimensional accuracy of bending parts and reduce the product quality. Therefore, it is of great significance to study the weld movement and springback in the bending forming process of welded plate. In order to effectively control the weld movement and springback of welded plate cap parts in bending forming process, the finite element models of transverse welded plate cap parts and longitudinal welded plate cap parts are established, and the bending forming process and springback process after unloading are simulated by using the finite element software DYNAFORM, and the blank holder force is mainly analyzed in this paper. Effects of friction coefficient, punch fillet radius, concave die fillet radius and material thickness ratio on weld movement and springback. In addition, the effects of blank holder force, material thickness ratio and weld position on the bending forming of transverse and longitudinal welded plate cap parts (weld inclined to thin side or inclined to thick side) where the weld is not in the middle position are studied. In this paper, the blank holder force is studied in detail, and the effects of different combinations of constant blank holder force on weld movement and springback are studied. on this basis, the effects of the initial blank holder force, the change point of blank holder force with punch stroke and the high pressure edge force on weld movement and springback in variable blank holder force are studied. Based on the above research, aiming at the bending forming of transverse, longitudinal welded plate cap parts and transverse, longitudinal asymmetric welded plate cap parts, a method is proposed, which can effectively reduce the weld movement and springback: in the initial stage of forming, a small and reasonable combination of thin and thick side blank holder force is applied to ensure the small weld movement. When the punch stroke is close to the total bending stroke, the thin and thick side blank holder force is increased at the same time, and the springback is reduced.
【學(xué)位授予單位】：燕山大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TG386

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 張福祥;陳煒;楊繼昌;仲志剛;方禾;朱國璋;;拼焊板在盒形件拉伸過程中的焊縫移動研究[J];金屬成形工藝;2002年05期

2 段永川;官英平;趙軍;;拼焊寬板V形自由彎曲回彈預(yù)測及試驗驗證[J];機(jī)械工程學(xué)報;2012年20期

3 夏江梅;;壓邊力對雙焊縫差厚拼焊板拉延成形焊縫移動的影響[J];熱加工工藝;2012年07期

相關(guān)碩士學(xué)位論文 前1條

1 呂安松;拼焊板彎曲成形數(shù)值模擬研究[D];燕山大學(xué);2009年

，

本文編號：2511225