【摘要】：多點(diǎn)成形是一種新型的板材柔性成形技術(shù),目前已經(jīng)廣泛應(yīng)用于航空航天、船體外板、汽車(chē)覆蓋件、建筑外觀等制造領(lǐng)域。隨著板材加工技術(shù)的不斷發(fā)展,人們對(duì)產(chǎn)品的個(gè)性化要求也越來(lái)越高,因此本文提出柔性拉邊多點(diǎn)對(duì)壓成形技術(shù)。它是利用多點(diǎn)模具對(duì)金屬板材進(jìn)行對(duì)壓成形,采用四周拉邊的方式,由離散夾鉗夾緊板材,并對(duì)板材施加垂直板材方向的正壓力和平行板材方向的拉邊力,保證夾鉗與板材始終不發(fā)生脫離現(xiàn)象,從而成形出復(fù)雜曲面件的一種板材加工方法。與其他沖壓技術(shù)相比,該技術(shù)不僅可以成形出質(zhì)量更好、形狀更加復(fù)雜的曲面件,還可以通過(guò)調(diào)整上、下基本體群的模具型面實(shí)現(xiàn)板材的快速成形。本文詳細(xì)介紹了柔性拉邊多點(diǎn)成形工藝的研究背景、基本原理及設(shè)備結(jié)構(gòu)。以球形件和馬鞍件為例,利用ABAQUS有限元分析軟件建立了板材柔性拉邊多點(diǎn)對(duì)壓成形有限元模型,并對(duì)不同的工藝參數(shù)進(jìn)行了一系列的數(shù)值模擬分析。具體研究?jī)?nèi)容如下:1.以球形件和馬鞍件為例,建立了剛性壓邊、柔性壓邊和柔性拉邊三種多點(diǎn)對(duì)壓成形工藝的有限元模型,并對(duì)其數(shù)值模擬結(jié)果進(jìn)行了詳細(xì)的對(duì)比分析。結(jié)果表明:剛性壓邊多點(diǎn)成形得到的成形件的直壁區(qū)出現(xiàn)應(yīng)力集中現(xiàn)象,容易出現(xiàn)拉裂缺陷;柔性壓邊多點(diǎn)成形得到的成形件邊緣區(qū)處的柔性壓邊圈與工件曲面變化趨勢(shì)一致,但其應(yīng)力應(yīng)變不均勻,邊角處容易出現(xiàn)起皺缺陷;柔性拉邊多點(diǎn)成形得到的成形件邊緣區(qū)處的離散夾鉗排列方式與板材變形趨勢(shì)一致,應(yīng)力應(yīng)變分布均勻,不易出現(xiàn)拉裂和起皺缺陷,成形效果最好。2.研究了夾鉗數(shù)量、拉邊力、材料參數(shù)及摩擦系數(shù)對(duì)柔性拉邊多點(diǎn)成形結(jié)果的影響。結(jié)果表明:離散夾鉗的數(shù)量越多,成形件應(yīng)力應(yīng)變?cè)骄鶆?工件的質(zhì)量越好;在一定范圍內(nèi),拉邊力越大,板材受力時(shí)材料流動(dòng)性越好,成形件變形越均勻;與2024鋁板相比,屈服強(qiáng)度較大的08AL鋼板容易得到質(zhì)量較好的成形件;摩擦系數(shù)越小,彈性墊和金屬板材之間的接觸阻力越小,板材變形時(shí)內(nèi)部金屬流動(dòng)性更好,成形效果也更好。3.研究了彈性墊厚度對(duì)柔性拉邊多點(diǎn)成形結(jié)果的影響。結(jié)果表明:彈性墊厚度越大,成形后工件的表面接觸應(yīng)力越小,分布越均勻,壓痕缺陷逐漸消失,但是其精度會(huì)隨之下降。
[Abstract]:Multi-point forming is a new type of sheet metal flexible forming technology, which has been widely used in aerospace, hull outer plate, automobile panel, building appearance and other manufacturing fields. With the development of sheet metal processing technology, the individuation requirement of products is becoming more and more high, so this paper puts forward the flexible edge drawing multi-point pressing forming technology. It uses multi-point die to press the sheet metal, uses the way of drawing the edge around, clamps the plate by the discrete clamp, and exerts the positive pressure in the vertical direction of the plate and the pull force in the direction of the parallel plate. It is ensured that the clamping clamp and the sheet metal do not break away from each other at all times, thus forming a kind of sheet metal processing method for complex curved surface parts. Compared with other stamping technologies, this technology can not only produce better quality and more complicated curved surface, but also realize rapid forming of sheet metal by adjusting the top and bottom basic body groups' die surfaces. In this paper, the research background, basic principle and equipment structure of flexible edge drawing multipoint forming process are introduced in detail. Taking spherical parts and saddle parts as examples, the finite element model of multi-point compression forming for flexible edge drawing of sheet metal was established by using ABAQUS finite element analysis software, and a series of numerical simulation analysis for different technological parameters were carried out. The specific research contents are as follows: 1. Taking spherical parts and saddle parts as examples, the finite element models of rigid blank holder, flexible blank holder and flexible edge drawing are established, and the numerical simulation results are compared and analyzed in detail. The results show that the stress concentration in the straight wall of the forming parts obtained by multi-point forming with rigid blank holder is obvious, and the tensile cracks are easy to appear. The change trend of the flexible edge holder is the same as that of the workpiece surface, but the stress and strain are not uniform, and the wrinkle defect is easy to appear at the edge corner. The discrete clamp arrangement at the edge of the forming part obtained by flexible drawing multi-point forming is consistent with the deformation trend of the sheet metal, the stress and strain distribution is uniform, the defects of tensile crack and wrinkle are not easy to appear, and the forming effect is the best. 2. The effects of the number of clamps, drawing force, material parameters and friction coefficient on the multi-point forming results of flexible edge drawing were studied. The results show that the more the number of discrete clamps, the more uniform the stress and strain of the forming parts, the better the quality of the workpiece, the greater the drawing force, the better the material fluidity and the more uniform the deformation of the forming parts. Compared with 2024 aluminum sheet, the 08AL sheet with higher yield strength is easy to obtain the forming parts with better quality. The smaller the friction coefficient, the smaller the contact resistance between the elastic pad and the sheet metal, the better the metal fluidity and the better forming effect when the sheet is deformed. The effect of the thickness of elastic pad on the results of flexible edge drawing multipoint forming was studied. The results show that the greater the thickness of the elastic pad, the smaller the surface contact stress, the more uniform the distribution, and the less the indentation defect is, but the lower the precision is.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2016
【分類(lèi)號(hào)】：TG306

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 Kumar Balan;;噴丸強(qiáng)化技術(shù)的應(yīng)用[J];金屬加工(熱加工);2008年19期

2 錢(qián)直睿;李明哲;孫剛;譚富星;金文姬;;球形面多道次多點(diǎn)成形的數(shù)值模擬[J];吉林大學(xué)學(xué)報(bào)(工學(xué)版);2007年02期

3 曾元松;尚建勤;許春林;喬明杰;王俊彪;董錦亮;;ARJ21飛機(jī)大型超臨界機(jī)翼整體壁板噴丸成形技術(shù)[J];航空制造技術(shù);2007年03期

4 朱虎;姜在寬;;基于數(shù)控機(jī)床的金屬板材無(wú)模單點(diǎn)漸進(jìn)成形研究[J];鍛壓技術(shù);2007年01期

5 張鵬;季忠;;板料激光曲線彎曲成形溫度場(chǎng)的數(shù)值研究[J];制造技術(shù)與機(jī)床;2006年11期

6 曾元松;黃遐;李志強(qiáng);;先進(jìn)噴丸成形技術(shù)及其應(yīng)用與發(fā)展[J];塑性工程學(xué)報(bào);2006年03期

7 付文智,李明哲,李東平,陳雪;多點(diǎn)成形壓力機(jī)及成形工藝的最新進(jìn)展[J];機(jī)械科學(xué)與技術(shù);2004年12期

8 莫健華,丁勇,黃樹(shù)槐;金屬板材數(shù)控單點(diǎn)漸進(jìn)成形加工軌跡優(yōu)化研究[J];中國(guó)機(jī)械工程;2003年24期

9 劉順洪,周龍?jiān)?萬(wàn)鵬騰;激光誘發(fā)熱應(yīng)力成形的研究[J];激光技術(shù);2001年04期

10 王秀鳳,JanosTakacs,GyorgyKrallics;薄板激光彎曲機(jī)理的研究[J];鍛壓技術(shù);2001年04期

相關(guān)博士學(xué)位論文 前4條

1 陳雪;基于離散夾鉗與多點(diǎn)模具的板材柔性拉形技術(shù)研究[D];吉林大學(xué);2011年

2 馬琳偉;金屬板材單點(diǎn)漸進(jìn)成形數(shù)值模擬及機(jī)理研究[D];華中科技大學(xué);2008年

3 裴繼斌;船用鋼板激光彎曲成形機(jī)理及成形規(guī)律的研究[D];大連理工大學(xué);2008年

4 沈洪;激光彎曲成形的精度控制研究[D];上海交通大學(xué);2007年

相關(guān)碩士學(xué)位論文 前3條

1 李穎超;金屬板料單點(diǎn)漸進(jìn)成形數(shù)值模擬與工藝研究[D];江蘇科技大學(xué);2012年

2 張國(guó)威;基于多點(diǎn)成形的板料復(fù)合漸進(jìn)成形數(shù)值模擬[D];吉林大學(xué);2010年

3 李茂君;基于數(shù)值模擬的板材漸進(jìn)成形回彈研究[D];華中科技大學(xué);2008年

，

本文編號(hào)：2384454