彎折片多工位沖壓級進(jìn)模具設(shè)計【含20張CAD圖紙+PDF圖】

喜歡這套資料就充值下載吧。資源目錄里展示的都可在線預(yù)覽哦。下載后都有，請放心下載，文件全都包含在內(nèi)，【有疑問咨詢QQ:1064457796 或 1304139763】=喜歡這套資料就充值下載吧。資源目錄里展示的都可在線預(yù)覽哦。下載后都有，請放心下載，文件全都包含在內(nèi)，【有疑問咨詢QQ:1064457796 或 1304139763】= 本 科 畢 業(yè) 設(shè) 計題 目 彎折片模具設(shè)計 學(xué) 院 工業(yè)制造學(xué)院 專 業(yè) 材料成型及控制工程 學(xué)生姓名 張 蓉 學(xué) 號 200910112116 年級 09級一班 指導(dǎo)教師 張維平 職稱 副教授 2013 年 5月 30 日成都學(xué)院學(xué)士學(xué)位論文（設(shè)計）彎折片模具設(shè)計專業(yè)：材料成型及控制工程 學(xué) 號：200910112116學(xué)生： 張蓉 指導(dǎo)老師：張維平摘要：沖壓是利用安裝在沖壓設(shè)備（主要是壓力機(jī)）上的模具對材料施加壓力，使其產(chǎn)生分離或塑性變形，從而獲得所需零件的一種壓力加工方法。彎曲是將板料、棒料、管材和型材彎曲成一定角度和形狀的沖壓成形工序。本設(shè)計對指定工件進(jìn)行的級進(jìn)模設(shè)計，利用Auto CAD軟件對制件進(jìn)行設(shè)計繪圖，明確了設(shè)計思路，確定了沖壓成型工藝過程并對各個具體部分進(jìn)行了詳細(xì)的計算和校核。利用鋁合金零件特征之間的關(guān)系建立級進(jìn)模排樣設(shè)計模型，引如沖壓排樣設(shè)計原則；進(jìn)一步將鋁合金零件的形狀特征應(yīng)用于模具結(jié)構(gòu)設(shè)計中，建立模具模型，進(jìn)行模具工藝設(shè)計和結(jié)構(gòu)設(shè)計，從而確定總體的模具形式；模具投入制造后，可能在制造和生產(chǎn)過程中表現(xiàn)出設(shè)計的不足和錯誤，通過總結(jié)概括這些問題，可以進(jìn)行模具結(jié)構(gòu)設(shè)計，或增加新的工藝規(guī)則，為以后的模具設(shè)計提供寶貴的經(jīng)驗。關(guān)鍵詞：鋁合金零件 ； 級進(jìn)模 ；排樣設(shè)計 Bending stamping die designSpecialty：The Material Forming and Controlling Engineering Number： 200910112116Student：Zhang Rong Supervisor：Zhang WeipingAbstract：Stamping is installed in the use of stamping equipment (mainly press) on the mold to exert pressure on the materials to produce plastic deformation or separation, to obtain the necessary components of a pressure processing methods. Sheet metal bending is, bar, pipe-bending and profiles some perspective and shape of the stamping process. The design of the suspension by the progressive die design, the use of Auto CAD software to design parts drawing. Clear design ideas, determine the process of stamping and forming part of the various specific details of the calculation and verification. The use of aluminum alloy parts to establish the relationship between the characteristics of the Progressive Die layout design models, such as punching with layout design principles; further aluminum alloy parts components used in the shape of die structure design, create a model die, die design and technology Structural design, to determine the overall form of the mold; Die in manufacturing, may be in the manufacturing and production process of debugging demonstrated the inadequacies and errors in design, through the speech summed up these problems, that can die structure design, new or increased Technology rules, the die design for the future provide a valuable experience. Key Words：Aluminum Alloy Parts；Progressive Die；Layout Design目 錄1緒論11.1 模具行業(yè)的發(fā)展現(xiàn)狀及市場前景11.2 沖壓模地位及我國沖壓技術(shù)11.2.1 沖壓模相關(guān)介紹11.2.2 沖模在現(xiàn)代工業(yè)生產(chǎn)中的地位21.3 沖壓行業(yè)阻力和障礙與突破22 零件的工藝性分析52.1 設(shè)計題目52.2 工件的化學(xué)成分及機(jī)械性能分析52.3 成型工藝分析62.4 沖裁工藝方案的確定62.4.1 翻邊工藝分析62.4.2彎曲模具設(shè)計工藝73 方案的確定和毛坯尺寸的確定83.1 零件毛胚尺寸83.2 零件排樣及利用率94 模具主要零部件的結(jié)構(gòu)設(shè)計114.1 凸、凹模結(jié)構(gòu)設(shè)計的原則114.2 沖孔凸模的設(shè)計114.2.1沖孔刃口計算114.2.2 凸模長度的計算124.3 落料凸模的設(shè)計134.3.1 落料刃口尺寸的計算134.3.2 落料凸模的設(shè)計134.4 翻邊凸模的設(shè)計144.4.1 翻邊模具工作刃口尺寸計算144.4.2 翻邊模具的長度設(shè)計154.5 彎曲模具的設(shè)計174.5.1 彎曲模的刃口尺寸計算174.5.2 彎曲模的高度計算184.6 拉深部分的的尺寸計算195 沖壓力及壓力中心計算215.1 主要工藝的計算215.1.1 沖孔力的計算215.1.2 落料力的計算215.1.3 翻邊力的計算215.1.4 彎曲力的計算225.1.5拉深力的計算225.1.6 卸料力、推件力的計算225.2 總的沖裁力235.3 計算壓力中心236 設(shè)備的選用246.1 沖壓設(shè)備的確定246.2 卸料選擇246.3 導(dǎo)向裝置的選擇246.3.1導(dǎo)套結(jié)構(gòu)尺寸246.3.2 導(dǎo)柱結(jié)構(gòu)尺寸256.4 卸料彈簧的選用266.5 碟形彈簧的選用266.6模架的選擇266.7 模柄的選擇277 其余零件的選用與標(biāo)準(zhǔn)化297.1 凸模固定板297.2 墊板297.3 卸料板298 裝配圖及其他說明308.1 繪制裝配圖308.2 其他說明309設(shè)計小結(jié)32參考文獻(xiàn)33致謝34 II1緒論1.1 模具行業(yè)的發(fā)展現(xiàn)狀及市場前景現(xiàn)代模具工業(yè)有“不衰亡工業(yè)”之稱。世界模具市場總體上供不應(yīng)求，市場需求量維持在600億至650億美元，同時，我國的模具產(chǎn)業(yè)也迎來了新一輪的發(fā)展機(jī)遇。近幾年，我國模具產(chǎn)業(yè)總產(chǎn)值保持13%的年增長率（據(jù)不完全統(tǒng)計，2004年國內(nèi)模具進(jìn)口總值達(dá)到600多億，同時，有近200個億的出口），到2005年模具產(chǎn)值預(yù)計為600億元，模具及模具標(biāo)準(zhǔn)件出口將從現(xiàn)在的每年9000多萬美元增長到2005年的2億美元左右。單就汽車產(chǎn)業(yè)而言，一個型號的汽車所需模具達(dá)幾千副，價值上億元，而當(dāng)汽車更換車型時約有80%的模具需要更換。2003年我國汽車產(chǎn)銷量均突破400萬輛，預(yù)計2004年產(chǎn)銷量各突破500萬輛，轎車產(chǎn)量將達(dá)到260萬輛。另外，電子和通訊產(chǎn)品對模具的需求也非常大，在發(fā)達(dá)國家往往占到模具市場總量的20%之多。目前，中國17000多個模具生產(chǎn)廠點，從業(yè)人數(shù)約50多萬。1999年中國模具工業(yè)總產(chǎn)值已達(dá)245億元人民幣。工業(yè)總產(chǎn)值中企業(yè)自產(chǎn)自用的約占三分之二，作為商品銷售的約占三分之一。在模具工業(yè)的總產(chǎn)值中，沖壓模具約占50%，塑料模具約占33%，壓鑄模具約占6%，其它各類模具約占11%。1.2 沖壓模地位及我國沖壓技術(shù) 1.2.1 沖壓模相關(guān)介紹 冷沖壓:是在常溫下利用沖模在壓力機(jī)上對材料施加壓力，使其產(chǎn)生分離或變形，從而獲得一定形狀、尺寸和性能的零件的加工方法。沖壓可分為五個基本工序：沖裁、彎曲、拉深、成形和立體壓制。沖壓模具:在冷沖壓加工中，將材料（金屬或非金屬）加工成零件（或半成品）的一種特殊工藝裝備，稱為冷沖壓模具（俗稱冷沖模）。 沖壓模按照工序組合分為三類：單工序模、復(fù)合模和級進(jìn)模。復(fù)合模與單工序模相比減少了沖壓工藝，其結(jié)構(gòu)緊湊，面積較?。粵_出的制件精度高，工件表面較平直，特別是孔與制件的外形同步精度容易保證；適于沖薄料，可充分利用短料和邊角余料；適合大批量生產(chǎn)，生產(chǎn)率高，所以得到廣泛應(yīng)用，但模具結(jié)構(gòu)復(fù)雜，制造困難。沖壓模具是沖壓生產(chǎn)必不可少的工藝裝備，是技術(shù)密集型產(chǎn)品。沖壓件的質(zhì)量、生產(chǎn)效率以及生產(chǎn)成本等，與模具設(shè)計和制造有直接關(guān)系。模具設(shè)計與制造技術(shù)水平的高低，是衡量一個國家產(chǎn)品制造水平高低的重要標(biāo)志之一，在很大程度上決定著產(chǎn)品的質(zhì)量、效益和新產(chǎn)品的開發(fā)能力。 1.2.2 沖模在現(xiàn)代工業(yè)生產(chǎn)中的地位 在現(xiàn)代工業(yè)生產(chǎn)中，沖模約占模具工業(yè)的50%，在國民經(jīng)濟(jì)各個部門，特別是汽車、航空航天、儀器儀表、機(jī)械制造、家用電器、石油化工、輕工日用品等工業(yè)部門得到極其廣泛的應(yīng)用。據(jù)統(tǒng)計，利用沖模制造的零件，在飛機(jī)、汽車、電機(jī)電器、儀器儀表等機(jī)電產(chǎn)品中占60%70%，在電視機(jī)、錄音機(jī)、計算機(jī)等電子產(chǎn)品中占80%以上，在自行車、手表、洗衣機(jī)、電冰箱、電風(fēng)扇等輕工產(chǎn)品中占85%以上。在各種類型的汽車中，平均一個車型需要沖壓模具2000套，其中大中型覆蓋件模具300套。1.3 沖壓行業(yè)阻力和障礙與突破 阻力一：機(jī)械化、自動化程度低美國680條沖壓線中有70%為多工位壓力機(jī)，日本國內(nèi)250條生產(chǎn)線有32%為多工位壓力機(jī)，而這種代表當(dāng)今國際水平的大型多工位壓力機(jī)在我國的應(yīng)用卻為數(shù)不多；中小企業(yè)設(shè)備普遍較落后，耗能耗材高，環(huán)境污染嚴(yán)重；封頭成形設(shè)備簡陋，手工操作比重大；精沖機(jī)價格昂貴，是普通壓力機(jī)的510倍，多數(shù)企業(yè)無力投資阻礙了精沖技術(shù)在我國的推廣應(yīng)用；液壓成形，尤其是內(nèi)高壓成形，設(shè)備投資大，國內(nèi)難以起步。突破點：加速技術(shù)改造要改變當(dāng)前大部分還是手工上下料的落后局面，結(jié)合具體情況，采取新工藝，提高機(jī)械化、自動化程度。汽車車身覆蓋件沖壓應(yīng)向單機(jī)連線自動化、機(jī)器人沖壓生產(chǎn)線，特別是大型多工位壓力機(jī)方向發(fā)展。爭取加大投資力度，加速沖壓生產(chǎn)線的技術(shù)改造，使盡早達(dá)到當(dāng)今國際水平。而隨著微電子技術(shù)和通訊技術(shù)的發(fā)展使板材成形裝備自動化、柔性化有了技術(shù)基礎(chǔ)。應(yīng)加速發(fā)展數(shù)字化柔性成形技術(shù)、液壓成形技術(shù)、高精度復(fù)合化成形技術(shù)以及適應(yīng)新一代輕量化車身結(jié)構(gòu)的型材彎曲成形技術(shù)及相關(guān)設(shè)備。同時改造國內(nèi)舊設(shè)備，使其發(fā)揮新的生產(chǎn)能力。阻力二：生產(chǎn)集中度低許多汽車集團(tuán)大而全，形成封閉內(nèi)部配套，導(dǎo)致各企業(yè)的沖壓件種類多，生產(chǎn)集中度低，規(guī)模小，易造成低水平的重復(fù)建設(shè)，難以滿足專業(yè)化分工生產(chǎn)，市場競爭力弱；摩托車沖壓行業(yè)面臨激烈的市場競爭，處于“優(yōu)而不勝，劣而不汰”的狀態(tài)；封頭制造企業(yè)小而散，集中度僅39.2%。突破點：走專業(yè)化道路迅速改變目前“大而全”、“散亂差”的格局，盡快從汽車集團(tuán)中把沖壓零部件分離出來，按沖壓件的大、中、小分門別類，成立幾個大型的沖壓零部件制造供應(yīng)中心及幾十個小而專的零部件工廠。通過專業(yè)化道路，才能把沖壓零部件做大做強(qiáng)，成為國際上有競爭實力的沖壓零部件供應(yīng)商。阻力三：沖壓板材自給率不足，品種規(guī)格不配套目前，我國汽車薄板只能滿足60%左右，而高檔轎車用鋼板，如高強(qiáng)度板、合金化鍍鋅板、超寬板(1650mm以上)等都依賴進(jìn)口。突破點：所用的材料應(yīng)與行業(yè)協(xié)調(diào)發(fā)展汽車用鋼板的品種應(yīng)更趨向合理，朝著高強(qiáng)、高耐蝕和各種規(guī)格的薄鋼板方向發(fā)展，并改善沖壓性能。鋁、鎂合金已成為汽車輕量化的理性材料，擴(kuò)大應(yīng)用已勢在必行。阻力四：科技成果轉(zhuǎn)化慢先進(jìn)工藝推廣慢在我國，許多沖壓新技術(shù)起步并不晚，有些還達(dá)到了國際先進(jìn)水平，但常常很難形成生產(chǎn)力。先進(jìn)沖壓工藝應(yīng)用不多，有的僅處于試用階段，吸收、轉(zhuǎn)化、推廣速度慢。技術(shù)開發(fā)費用投入少，導(dǎo)致企業(yè)對先進(jìn)技術(shù)的掌握應(yīng)用慢，開發(fā)創(chuàng)新能力不足，中小企業(yè)在這方面的差距更甚。目前，國內(nèi)企業(yè)大部分仍采用傳統(tǒng)沖壓技術(shù)，對下一代輕量化汽車結(jié)構(gòu)和用材所需的成形技術(shù)缺少研究與技術(shù)儲備。突破點：走產(chǎn)、學(xué)、研聯(lián)合之路我國與歐、美、日等相比，存在的最大的差距就是還沒有一個產(chǎn)、學(xué)研聯(lián)合體，科研難以做大，成果不能盡快轉(zhuǎn)化為生產(chǎn)力。所以應(yīng)圍繞大型開發(fā)和產(chǎn)業(yè)化項目，以高校和科研單位為技術(shù)支持，企業(yè)為應(yīng)用基地，形成產(chǎn)品、設(shè)備、材料、技術(shù)的企業(yè)聯(lián)合實體，形成既能開發(fā)創(chuàng)新，又能迅速產(chǎn)業(yè)化的良性循環(huán)。阻力五：大、精模具依賴進(jìn)口當(dāng)前，沖壓模具的材料、設(shè)計、制作均滿足不了國內(nèi)汽車發(fā)展的需要，而且標(biāo)準(zhǔn)化程度尚低，大約為40%45%，而國際上一般在70%左右。突破點：提升信息化、標(biāo)準(zhǔn)化水平必須用信息化技術(shù)改造模具企業(yè)，發(fā)展重點在于大力推廣CAD/CAM/CAE一體化技術(shù)，特別是成形過程的計算機(jī)模擬分析和優(yōu)化技術(shù)(CAE)。加速我國模具標(biāo)準(zhǔn)化進(jìn)程，提高精度和互換率。力爭2005年模具標(biāo)準(zhǔn)件使用覆蓋率達(dá)到60%，2010年達(dá)到70%以上基本滿足市場需求。 阻力六：專業(yè)人才缺乏業(yè)內(nèi)掌握先進(jìn)設(shè)計分析技術(shù)和數(shù)字化技術(shù)的高素質(zhì)人才遠(yuǎn)遠(yuǎn)不能滿足沖壓行業(yè)飛速發(fā)展的需要，尤其是摩托車行業(yè)中具備沖壓知識和技術(shù)和技能的專業(yè)人才更為缺乏且大量外流。另外，眾多合資公司由外方進(jìn)行工程設(shè)計，掌握設(shè)計權(quán)、投資權(quán)，我方?jīng)_壓技術(shù)人員難以真正掌握沖壓工藝的真諦。突破點：提高行業(yè)人員素質(zhì)這是一項迫在眉睫的任務(wù)，又是一項長期而系統(tǒng)的任務(wù)。振興我國沖壓行業(yè)需要大批高水平的科技人才，大批熟悉國內(nèi)外市場、具有現(xiàn)代管理知識和能力的企業(yè)家，大批掌握先進(jìn)技術(shù)、工藝的高級技能人才。要舍得花大力氣，有計劃、分層次地培養(yǎng)2 零件的工藝性分析2.1 設(shè)計題目 工件簡圖如下：根據(jù)所給題目利用solidworks三維建模所得模型圖如圖：材料:鋁材 厚度:3mm 2.2 工件的化學(xué)成分及機(jī)械性能分析 此設(shè)計中的零件材料為鋁材，因為純鋁較軟，是面心立方結(jié)構(gòu)，故具有很高的塑性（:3240%，7090%），易于加工，可制成各種型材、板材?？垢g性能好；但是純鋁的強(qiáng)度很低，退火狀態(tài) b 值約為8kgf/mm2，故不宜作結(jié)構(gòu)材料。通過長期的生產(chǎn)實踐和科學(xué)實驗，人們逐漸以加入合金元素及運用等方法來強(qiáng)化鋁，本畢業(yè)設(shè)計為設(shè)計彎折片，鎂鋁6061-T651是6系合金的主要合金，是經(jīng)熱處理預(yù)拉伸工藝的高品質(zhì)鋁合金產(chǎn)品；鎂鋁6061具有加工性能極佳、良好的抗腐蝕性、韌性高及加工后不變形、上色膜容易、氧化效果極佳等優(yōu)良特點，故使用6061鋁合金最好。從零件圖知道，該制件并沒有公差要求，故按照自由公差計算，故制件的公差取IT14級。因為制件的精度相對較低，故模具的精度也相對較低，所以模具的加工成本也會降低。6061的力學(xué)強(qiáng)度如下 ： 抗拉強(qiáng)度 b (MPa) 200Mpa條件屈服強(qiáng)度 0.2 (MPa)276Mpa抗剪強(qiáng)度 205Mpa 狀態(tài)T6硬度：HB90-110延伸率：11%2.3 成型工藝分析此工件材料為6061，厚度為3mm。具有良好的沖壓性能，適合沖裁，但主要難點在于 2個凸臺的成形，以及三角形拉深的成型。2.4 沖裁工藝方案的確定 因為此零件比較復(fù)雜，此畢業(yè)設(shè)計采用一套多工位級進(jìn)模具，工作順序為先在板料上打兩個孔，再進(jìn)行落料，再對兩個孔進(jìn)行翻邊，然后再對板材進(jìn)行折彎，最后再進(jìn)行三角形拉深，因為拉深的部分和折彎的部分有重合，容易在拉深的時候損壞零件，所以調(diào)整為折彎和拉深同時進(jìn)行。下面對難點進(jìn)行分析。2.4.1 翻邊工藝分析 翻邊工藝計算有兩方面的內(nèi)容：一是要根據(jù)翻孔的孔徑，計算毛坯預(yù)制孔的尺寸；二是要根據(jù)允許的極限翻孔系數(shù)，校核一次翻孔可能達(dá)到的翻孔高度。平板毛坯翻孔預(yù)制孔直徑d可以近似地安彎曲展開計算，D=9mm,r=0.5mm,h=3mm,t=3mm=(r+)+h將D=D+2r+t=9+1+3=13mm及H=h+r+t=6.5mm代入上式并整理可得預(yù)孔直徑d=5.12mm。一次翻孔的極限高度，可以根據(jù)極限翻孔系數(shù)及預(yù)制孔直徑d推導(dǎo)求得：即 H=+0.43r+0.72t=(1-) +0.43r+0.72t 式中=K所以最大翻邊高度 H=(1-K)+0.43r+0.72t其中 ： D翻邊后的中經(jīng)(mm) K極限翻邊系數(shù) r翻邊圓角半徑(mm) t材料厚度(mm)于是 H=3.092mm,因為工件翻邊高度H2t,該零件滿足。彎曲件有回彈值應(yīng)減少回彈值，影響回彈的因素很多，如材料的力學(xué)性能，工件的相對彎曲半徑r/t，彎曲中心角的大小，彎曲工件的形狀，彎曲方式，模具間隙等，因此很難用精確的計算方法得出回彈值的大小，一般是按表格或圖表查出經(jīng)驗數(shù)值，或按計算法求出回彈角后，再在生產(chǎn)實踐中試模修正。60611屈服強(qiáng)度為：276MPA，屬中強(qiáng)度鋁合金。當(dāng)彎曲件的相對半徑r/t0.5 式中：R彎曲半徑（mm） t材料厚度（mm） 由于相對彎曲半徑大于0.5，可見制件屬于圓角半徑較大的彎曲件，應(yīng)該先求變形區(qū)中性層曲率半徑，=r+kt 式中：r彎曲件內(nèi)層的彎曲半徑 t材料厚度 k中性層系數(shù) k值可參照下表注：k1適用于有頂板V形件或U件彎曲,k2適用于無頂板V形件彎曲。 查表得k=0.46根據(jù)公式 = r+kt=6+0.46x3 =7.38mm根據(jù)零件圖上得知，圓角半徑較大（R0.5t），彎曲件毛坯的長度公式為： L=L1+L2+L3+(r+kt) 式中：L彎曲件毛坯張開長度 （mm） 圓弧部分弧長: s=a s=7.38x /2 所以L=93+25.65-2x(r+2)+s=114.67mm 工件尺寸展開圖3.2 零件排樣及利用率采用有廢料單行直排的排樣方式，查沖壓工藝與模具設(shè)計表2-8得a=2.2mm，a1=2.7mm。若模具采用無側(cè)壓裝置的導(dǎo)料板結(jié)構(gòu)，則條料上零件的步距為s=D+a= 114.67+2.2=116.87mm。查沖壓模具設(shè)計和加工計算速查手冊，表1-4得導(dǎo)板與條料間最小間隙Z=0.5mm，表1-5得條料寬度公差=2.0mm，表1-7得側(cè)刃切去料寬方向尺寸b=2.5mm，側(cè)刃定距時，側(cè)導(dǎo)板與條料間最小間隙Y=0.20mm。條料的寬度應(yīng)為 B = ( D+ 2a1+Z) = (116.87 + 2 2.7+ 0.5)=122.77mm,選用規(guī)格為 3mm1500mm1500mm 的板料，計算裁料方式如下：裁成寬122.77mm，長116.87mm的板料，則每張板料所出的零件數(shù)為 (1500122.77)(1500116.87)=259零件的排樣圖如下圖所示 ： 沖孔 落料 翻邊 彎曲和拉深排樣圖分為4個工位，各工位的工序內(nèi)容如下：第1工位：沖孔；第2工位：落料第3工位：對孔進(jìn)行翻邊；第4工位：彎曲和拉深一個進(jìn)料距離內(nèi)的材料利用率：=100%=100%=100%=95%式中：A 得到的制件的總面積 A 一個進(jìn)料距內(nèi)的毛胚面積 B 條料和帶料的寬度 L 進(jìn)料距離4 模具主要零部件的結(jié)構(gòu)設(shè)計4.1 凸、凹模結(jié)構(gòu)設(shè)計的原則 （1）凸模和凹模要有足夠的剛性與強(qiáng)度由于在高速連續(xù)作業(yè)的條件下，振動極大，就是在普通機(jī)床上沖制，由于連續(xù)作業(yè)，凸模、凹模的磨損也比一般模具大的多；在多工位級進(jìn)模中的許多凸模、凹模的受力狀態(tài)是不均勻、不對稱、不垂直的，模具的損壞可能性也較大。所以在允許的條件下，應(yīng)當(dāng)適當(dāng)增加其強(qiáng)度。在多工位級進(jìn)模設(shè)計中，一般采用強(qiáng)度較好的合金工具鋼制造，并要選擇合適的硬度，合理地安排熱處理。 （2）凸模和凹模必須便于穩(wěn)定安裝和更換多工位級進(jìn)模的凸摸、凹模必須要求安裝后具有穩(wěn)定性，這不僅能保證沖制精度，可以提高沖壓次數(shù)，從而擴(kuò)大了經(jīng)濟(jì)效果。對于各種不同沖壓工序的凸模、凹模之間都要保持穩(wěn)定的間隙，而且間隙應(yīng)當(dāng)均勻一致。多工位級進(jìn)模的凸模、凹模要有統(tǒng)一的基準(zhǔn)，各種不同沖壓性質(zhì)的凸模、凹模必須諧調(diào)一致。 （3）便于排料方便及時多工位級進(jìn)模的連續(xù)沖制過程中，絕不允許把余料帶在凸模上，或留在凹模工作面上，以免損壞模具。 （4）便于制造、測量和組裝4.2 沖孔凸模的設(shè)計4.2.1沖孔刃口計算查沖壓工藝與模具設(shè)計表2-3沖裁模初始雙面間隙Z/2?。?.060.10）t，Zmin=0.12mm Zmax=0.20mm， Z max - Z min=0.08mm對零件圖中未注公差的尺寸，沖壓件一般保證精度IT14，為了保證凸、凹模間初始間隙合理，凸、凹模要有較高的制造精度，并分別標(biāo)注公差，公差應(yīng)滿足：Tp + T d Z max - Z min , Tp T d式中：Tp 、T d 凸、凹模制造公差 Zmax、Zmin 凸、凹模最大與最小雙面間隙查互換性與技術(shù)測量表2-1簡單形狀沖裁時5.12mm的公差=0.30mm，磨損因數(shù)查現(xiàn)代模具工手冊表4-7得x=0.75。由現(xiàn)代模具工手冊表4-6查得： 沖孔凸、凹模的制造公差：Tp=0.02mm Td=0.02mm校核：Tp + T d =0.04mmZ max - Z min=0.08mm ,則凸模刃口尺寸:：d=(d+XT)=5.35mm d=（ d+Z min）=5.47mm4.2.2 凸模長度的計算 根據(jù)公式 L=+h 式中： 凸模固定板厚度 彈性卸料板厚度 導(dǎo)料板厚度 h 增加長度所以 L=40+35+30+5=110mm因為沖裁件形狀簡單，沖裁材料厚度等于3mm所以沖孔凸模選用材料為T8A鋼，淬硬處理。具體的凸模設(shè)計如下：4.3 落料凸模的設(shè)計 4.3.1 落料刃口尺寸的計算 查表落料凸凹模的制造公差由現(xiàn)代模具工手冊表4-6查得 凸=0.025mm. 凹=0.035mm ，磨損因數(shù)由表4-7查得 X=0.75 ，校核凸+凹=0.025+0.035Zmax-Zmin=0.03mm. d=(d+XT)=115.72mmd=（ d+Z min）=115.84mm4.3.2 落料凸模的設(shè)計落料凸模長度依公式L=+t+h 式中 ：凸模固定板厚度 彈性卸料板厚度 t 料厚 h增加長度所以L=40+35+3+5=83mm具體落料凸模設(shè)計如圖示：4.4 翻邊凸模的設(shè)計 4.4.1 翻邊模具工作刃口尺寸計算由于在翻邊過程中，材料沿切向伸長，因此其端面的材料變薄非常嚴(yán)重，根據(jù)材料的統(tǒng)一變形情況，翻邊凹模與翻邊凸模之間的間隙應(yīng)小于原來的材料厚度。 及2mmZ/213.5，所以所選彈簧是合適的。6.5 碟形彈簧的選用 碟形彈簧分為直列式和復(fù)合式兩種，這里采用直列式安裝，碟形彈簧的計算方式與圓柱形壓縮彈簧的計算方式相同，這里不一一計算，查沖壓模具設(shè)計和加工計算速查手冊表4-38選擇碟形彈簧彈簧5030。6.6模架的選擇通過查表得：凹模厚度修正系數(shù)k=0.30，所以由公式：厚度H=Kb=0.391.85=27.555mm（工件最大外形尺寸91.85）；凹模寬度B=b+2(1.527.555)=174.5mm；長度L=174.5+2(1.527.555)=344.46mm，凹模固定板的厚度取與凹模厚度相同，故凹模固定板厚度：H=30mm； 所以根據(jù)最新沖壓模具標(biāo)準(zhǔn)及應(yīng)用手冊表7-1可選對角導(dǎo)柱模架，如圖：凹模周界閉合高度上模座下模座導(dǎo)柱導(dǎo)套LB最小最大4002505540025070 402604014053 400250275320402604014053 6.7 模柄的選擇本沖壓模模柄選用壓入式模柄，與模座孔采用過渡配合H7/m6，并加銷釘以防轉(zhuǎn)動。這種模柄可較好地保證軸線與上模座的垂直度，適用于各種中、小型沖模，生產(chǎn)中最常見。結(jié)構(gòu)如下圖：7 其余零件的選用與標(biāo)準(zhǔn)化 7.1 凸模固定板模具中的固定板，又稱為安裝板，它的主要任務(wù)是對凸模固定，并通過它安裝在模座上。對凸模固定板的要求：1. 固定板必須能夠安裝全部凸模及其它的零部件并使之正常穩(wěn)定工作。這樣，就要求固定板有足夠的剛性和強(qiáng)度。一般固定板的厚度相當(dāng)于工作凸?？傞L度的2/5或更大一些。2.固定板的耐磨性要好。固定板可選用45鋼或T10A鋼，淬火硬度應(yīng)在HRC4245。3.對于較大的凸模或有較大側(cè)向力的凸模應(yīng)用過盈配合裝配，要有較大的過盈量。4.各型孔位置精度應(yīng)當(dāng)與卸料板保持同心。行之有效的辦法是給定凹模各孔位置精度5.凸模固定板的結(jié)構(gòu)形式：固定板采用整體型結(jié)構(gòu)，材料選用45鋼，淬火硬度為HRC4348，取凸模固定板的厚度為40mm。 7.2 墊板墊板主要是防止凸模和凹模中的鑲件在沖壓過程中，由于沖壓力的集中而把模座的接觸面壓壞。在高速沖壓時，最容易損傷凸模，所以一般在固定板與模座之間增設(shè)墊板。墊板需淬火處理HRC4348、，且兩面平行光潔。墊板尺寸的確定：一般模板長300以內(nèi)10-15，300-500一般15以上，這里確定為墊板厚度為15mm。 7.3 卸料板級進(jìn)模的卸料板的厚度一般要根據(jù)模具的大小來確定，一般模具比較小，跳的步數(shù)不多的情況下，厚度可以在12mm15mm之間。如果跳的步數(shù)比較多，模具比較長的話，卸料板的厚度還可以再厚一些，一般取凸模的40%，可取35mm。8 裝配圖及其他說明 8.1 繪制裝配圖由以上設(shè)計計算，并繪圖設(shè)計，該多工位級進(jìn)模裝配圖如下：8.2 其他說明 1.螺釘和圓柱銷按照 GB/T70.1-2000和GB/T119.1-2000標(biāo)準(zhǔn)來選擇 2.卸料彈簧和蝶形彈簧按照GB/T4459.4-1984和GB/T1972-2005標(biāo)準(zhǔn)來選擇 3.模柄按照J(rèn)B/T7646.1-2008標(biāo)準(zhǔn)來選擇 4.導(dǎo)柱與下模座選擇過盈配合H7/s6，導(dǎo)柱與導(dǎo)套選擇間隙配合H7/f6，導(dǎo)套與上模座選擇過盈配合H7/s69設(shè)計小結(jié)我設(shè)計的是彎折片，用的是多工位的級進(jìn)模，通過這次設(shè)計，把我大學(xué)幾年所學(xué)到的理論知識在實際的設(shè)計工作中綜合地加以運用。使這些知識得到鞏固發(fā)展，初步培養(yǎng)了我沖壓模具設(shè)計的獨立工作打下良好基礎(chǔ)，樹立正確的設(shè)計思路。在這個過程中，從白紙到完成模具總裝圖，零件圖，設(shè)計說明書。學(xué)到很多原本學(xué)到的但不是很懂的知識，了解了一些設(shè)計的原理和過程。例如，沖裁模具設(shè)計一般步驟：（1）沖裁件工藝性；（2）確定沖裁工藝方案；（3）選擇模具的結(jié)構(gòu)形式；（4）進(jìn)行必要的工藝計算；（5）選擇與確定模具的主要零部件的結(jié)構(gòu)與尺寸；(6) 選擇壓力機(jī)的型號；（7）繪制模具總裝圖及零件圖。還有更多的知識，在這里不做過多的敘述。雖然在這次設(shè)計過程中遇到很多問題與麻煩，但通過指導(dǎo)老師的耐心教導(dǎo)和幫助，克服了這些困難。在這次設(shè)計中，我總結(jié)了：要學(xué)會親自去嘗試，不要害怕失敗。失敗也是一份財富，經(jīng)歷也是一份擁有。此外，這次設(shè)計過程中還有許多不如意和不完善的地方，通過這次的經(jīng)歷，希望以后會越做越好！參考文獻(xiàn)1 宇海英，劉占軍 主編，沖壓工藝與模具設(shè)計，電子工業(yè)出版社，2011.82 楊占堯，主編，現(xiàn)代模具工手冊，化學(xué)工業(yè)出版社，2007.73 裘文言，張祖繼，瞿元賞 主編，機(jī)械制圖，高等教育出版社，2003.64 謝鐵邦，李柱，席宏卓 主編，互換性與技術(shù)測量，華中科技大學(xué)出版社，1998.95 楊占堯 主編，最新沖壓模具標(biāo)準(zhǔn)及應(yīng)用手冊，化學(xué)工業(yè)出版社，2010.106 黃云清 主編，公差配合與測量技術(shù)，機(jī)械工業(yè)出版社，2001.37 薛啓翔 編著，沖壓模具設(shè)計和加工計算速查手冊，化學(xué)工業(yè)出版社，2007.108 趙麗娟 冷岳峰 編著，機(jī)械幾何量精度設(shè)計與檢測，清華大學(xué)出版社2011.79 王新華 編著，沖模設(shè)計與制造實用計算手冊，機(jī)械工業(yè)出版社，2003.3 10 周本凱 編著，冷沖壓模具設(shè)計優(yōu)化設(shè)計與典型案例，機(jī)械工業(yè)出版社，2010.611 張正修 主編，沖模實用典型結(jié)構(gòu)圖集，機(jī)械工業(yè)出版社，2009.7 12 王新華 編著，復(fù)合模連續(xù)模典型結(jié)構(gòu)圖冊，機(jī)械工業(yè)出版社，2011.5致謝在設(shè)計完成之際，我首先向關(guān)心幫助和指導(dǎo)我的指導(dǎo)老師張維平張老師表示衷心的感謝并致以崇高的敬意！不管是從開始定方向還是在查資料準(zhǔn)備的過程中，張老師以其淵博的學(xué)識、嚴(yán)謹(jǐn)?shù)闹螌W(xué)態(tài)度、求實的工作作風(fēng)和他敏捷的思維給我留下了深刻的印象，一直都耐心地給予我指導(dǎo)和意見，使我在設(shè)計沖壓模具的方向上有了較大提高；同時也顯示了張老師高度的敬業(yè)精神和責(zé)任感。在此，我對張維平老師表示誠摯的感謝與衷心的祝福 在學(xué)校的學(xué)習(xí)生活即將結(jié)束，回顧四年來的學(xué)習(xí)經(jīng)歷，面對現(xiàn)在的收獲，我感到無限欣慰。為此，我向熱心幫助過我的班主任宋慧瑾老師以及所有任課老師和同學(xué)表示由衷的感謝!衷心地謝謝你們。最后，感謝在百忙之中評閱我的設(shè)計和參加答辯的各位老師!33第 26 頁 共 27 頁e pos 模具工業(yè)現(xiàn)狀Process simulation in stamping recent applications for product and process designAbstractProcess simulation for product and process design is currently being practiced in industry. However, a number of input variables have a significant effect on the accuracy and reliability of computer predictions. A study was conducted to evaluate the capability of FE-simulations for predicting part characteristics and process conditions in forming complex-shaped, industrial parts.In industrial applications, there are two objectives for conducting FE-simulations of the stamping process; (1) to optimize the product design by analyzing formability at the product design stage and (2) to reduce the tryout time and cost in process design by predicting the deformation process in advance during the die design stage. For each of these objectives, two kinds of FE-simulations are applied. Pam-Stamp, an incremental dynamic-explicit FEM code released by Engineering Systems Intl, matches the second objective well because it can deal with most of the practical stamping parameters. FAST_FORM3D, a one-step FEM code released by Forming Technologies, matches the first objective because it only requires the part geometry and not the complex process information.In a previous study, these two FE codes were applied to complex-shaped parts used in manufacturing automobiles and construction machinery. Their capabilities in predicting formability issues in stamping were evaluated. This paper reviews the results of this study and summarizes the recommended procedures for obtaining accurate and reliable results from FE simulations.In another study, the effect of controlling the blank holder force (BHF) during the deep drawing of hemispherical, dome-bottomed cups was investigated. The standard automotive aluminum-killed, drawing-quality (AKDQ) steel was used as well as high performance materials such as high strength steel, bake hard steel, and aluminum 6111. It was determined that varying the BHF as a function of stroke improved the strain distributions in the domed cups.Keywords: Stamping; Process ;stimulation; Process design1. IntroductionThe design process of complex shaped sheet metal stampings such as automotive panels, consists of many stages of decision making and is a very expensive and time consuming process. Currently in industry, many engineering decisions are made based on the knowledge of experienced personnel and these decisions are typically validated during the soft tooling and prototyping stage and during hard die tryouts. Very often the soft and hard tools must be reworked or even redesigned and remanufactured to provide parts with acceptable levels of quality.The best case scenario would consist of the process outlined in Fig. 1. In this design process, the experienced product designer would have immediate feedback using a specially design software called one-step FEM to estimate the formability of their design. This would allow the product designer to make necessary changes up front as opposed to down the line after expensive tooling has been manufactured. One-step FEM is particularly suited for product analysis since it does not require binder, addendum, or even most process conditions. Typically this information is not available during the product design phase. One-step FEM is also easy to use and computationally fast, which allows the designer to play “what if” without much time investment.Fig. 1. Proposed design process for sheet metal stampings. Once the product has been designed and validated, the development project would enter the “time zero” phase and be passed onto the die designer. The die designer would validate his/her design with an incremental FEM code and make necessary design changes and perhaps even optimize the process parameters to ensure not just minimum acceptability of part quality, but maximum achievable quality. This increases product quality but also increase process robustness. Incremental FEM is particularly suited for die design analysis since it does require binder, addendum, and process conditions which are either known during die design or desired to be known.The validated die design would then be manufactured directly into the hard production tooling and be validated with physical tryouts during which the prototype parts would be made. Tryout time should be decreased due to the earlier numerical validations. Redesign and remanufacturing of the tooling due to unforeseen forming problems should be a thing of the past. The decrease in tryout time and elimination of redesign/remanufacturing should more than make up for the time used to numerically validate the part, die, and process. Optimization of the stamping process is also of great importance to producers of sheet stampings. By modestly increasing ones investment in presses, equipment, and tooling used in sheet forming, one may increase ones control over the stamping process tremendously. It has been well documented that blank holder force is one of the most sensitive process parameters in sheet forming and therefore can be used to precisely control the deformation process.By controlling the blank holder force as a function of press stroke AND position around the binder periphery, one can improve the strain distribution of the panel providing increased panel strength and stiffness, reduced springback and residual stresses, increased product quality and process robustness. An inexpensive, but industrial quality system is currently being developed at the ERC/NSM using a combination of hydraulics and nitrogen and is shown in Fig. 2. Using BHF control can also allow engineers to design more aggressive panels to take advantage the increased formability window provided by BHF control.Fig. 2. Blank holder force control system and tooling being developed at the ERC/NSM labs.Three separate studies were undertaken to study the various stages of the design process. The next section describes a study of the product design phase in which the one-step FEM code FAST_FORM3D (Forming Technologies) was validated with a laboratory and industrial part and used to predict optimal blank shapes. Section 4 summarizes a study of the die design stage in which an actual industrial panel was used to validate the incremental FEM code Pam-Stamp (Engineering Systems Intl). Section 5 covers a laboratory study of the effect of blank holder force control on the strain distributions in deep drawn, hemispherical, dome-bottomed cups.2. Product simulation applicationsThe objective of this investigation was to validate FAST_FORM3D, to determine FAST_FORM3Ds blank shape prediction capability, and to determine how one-step FEM can be implemented into the product design process. Forming Technologies has provided their one-step FEM code FAST_FORM3D and training to the ERC/NSM for the purpose of benchmarking and research. FAST_FORM3D does not simulate the deformation history. Instead it projects the final part geometry onto a flat plane or developable surface and repositions the nodes and elements until a minimum energy state is reached. This process is computationally faster than incremental simulations like Pam-Stamp, but also makes more assumptions. FAST_FORM3D can evaluate formability and estimate optimal blank geometries and is a strong tool for product designers due to its speed and ease of use particularly during the stage when the die geometry is not available.In order to validate FAST_FORM3D, we compared its blank shape prediction with analytical blank shape prediction methods. The part geometry used was a 5in. deep 12in. by 15in. rectangular pan with a 1in. flange as shown in Fig. 3. Table 1 lists the process conditions used. Romanovskis empirical blank shape method and the slip line field method was used to predict blank shapes for this part which are shown in Fig. 4. Fig. 3. Rectangular pan geometry used for FAST_FORM3D validation.Table 1. Process parameters used for FAST_FORM3D rectangular pan validation Fig. 4. Blank shape design for rectangular pans using hand calculations. (a) Romanovskis empirical method; (b) slip line field analytical method.Fig. 5(a) shows the predicted blank geometries from the Romanovski method, slip line field method, and FAST_FORM3D. The blank shapes agree in the corner area, but differ greatly in the side regions. Fig. 5(b)(c) show the draw-in pattern after the drawing process of the rectangular pan as simulated by Pam-Stamp for each of the predicted blank shapes. The draw-in patterns for all three rectangular pans matched in the corners regions quite well. The slip line field method, though, did not achieve the objective 1in. flange in the side region, while the Romanovski and FAST_FORM3D methods achieved the 1in. flange in the side regions relatively well. Further, only the FAST_FORM3D blank agrees in the corner/side transition regions. Moreover, the FAST_FORM3D blank has a better strain distribution and lower peak strain than Romanovski as can be seen in Fig. 6.Fig. 5. Various blank shape predictions and Pam-Stamp simulation results for the rectangular pan. (a) Three predicted blank shapes; (b) deformed slip line field blank; (c) deformed Romanovski blank; (d) deformed FAST_FORM3D blank.Fig. 6. Comparison of strain distribution of various blank shapes using Pam-Stamp for the rectangular pan. (a) Deformed Romanovski blank; (b) deformed FAST_FORM3D blank.To continue this validation study, an industrial part from the Komatsu Ltd. was chosen and is shown in Fig. 7(a). We predicted an optimal blank geometry with FAST_FORM3D and compared it with the experimentally developed blank shape as shown in Fig. 7(b). As seen, the blanks are similar but have some differences.Fig. 7. FAST_FORM3D simulation results for instrument cover validation. (a) FAST_FORM3Ds formability evaluation; (b) comparison of predicted and experimental blank geometries.Next we simulated the stamping of the FAST_FORM3D blank and the experimental blank using Pam-Stamp. We compared both predicted geometries to the nominal CAD geometry (Fig. 8) and found that the FAST_FORM3D geometry was much more accurate. A nice feature of FAST_FORM3D is that it can show a “failure” contour plot of the part with respect to a failure limit curve which is shown in Fig. 7(a). In conclusion, FAST_FORM3D was successful at predicting optimal blank shapes for a laboratory and industrial parts. This indicates that FAST_FORM3D can be successfully used to assess formability issues of product designs. In the case of the instrument cover, many hours of trial and error experimentation could have been eliminated by using FAST_FORM3D and a better blank shape could have been developed.Fig. 8. Comparison of FAST_FORM3D and experimental blank shapes for the instrument cover. (a) Experimentally developed blank shape and the nominal CAD geometry; (b) FAST_FORM3D optimal blank shape and the nominal CAD geometry.3. Die and process simulation applicationsIn order to study the die design process closely, a cooperative study was conducted by Komatsu Ltd. of Japan and the ERC/NSM. A production panel with forming problems was chosen by Komatsu. This panel was the excavators cabin, left-hand inner panel shown in Fig. 9. The geometry was simplified into an experimental laboratory die, while maintaining the main features of the panel. Experiments were conducted at Komatsu using the process conditions shown in Table 2. A forming limit diagram (FLD) was developed for the drawing-quality steel using dome tests and a vision strain measurement system and is shown in Fig. 10. Three blank holder forces (10, 30, and 50ton) were used in the experiments to determine its effect. Incremental simulations of each experimental condition was conducted at the ERC/NSM using Pam-Stamp.Fig. 9. Actual product cabin inner panel.Table 2. Process conditions for the cabin inner investigation Fig. 10. Forming limit diagram for the drawing-quality steel used in the cabin inner investigation.At 10ton, wrinkling occurred in the experimental parts as shown in Fig. 11. At 30ton, the wrinkling was eliminated as shown in Fig. 12. These experimental observations were predicted with Pam-stamp simulations as shown in Fig. 13. The 30ton panel was measured to determine the material draw-in pattern. These measurements are compared with the predicted material draw-in in Fig. 14. Agreement was very good, with a maximum error of only 10mm. A slight neck was observed in the 30ton panel as shown in Fig. 13. At 50ton, an obvious fracture occurred in the panel.Fig. 11. Wrinkling in laboratory cabin inner panel, BHF=10ton.Fig. 12. Deformation stages of the laboratory cabin inner and necking, BHF=30ton. (a) Experimental blank; (b) experimental panel, 60% formed; (c) experimental panel, fully formed; (d) experimental panel, necking detail.Fig. 13. Predication and elimination of wrinkling in the laboratory cabin inner. (a) Predicted geometry, BHF=10ton; (b) predicted geometry, BHF=30ton.Fig. 14. Comparison of predicted and measured material draw-in for lab cabin inner, BHF=30ton.Strains were measured with the vision strain measurement system for each panel, and the results are shown in Fig. 15. The predicted strains from FEM simulations for each panel are shown in Fig. 16. The predictions and measurements agree well regarding the strain distributions, but differ slightly on the effect of BHF. Although the trends are represented, the BHF tends to effect the strains in a more localized manner in the simulations when compared to the measurements. Nevertheless, these strain prediction show that Pam-Stamp correctly predicted the necking and fracture which occurs at 30 and 50ton. The effect of friction on strain distribution was also investigated with simulations and is shown in Fig. 17.Fig. 15. Experimental strain measurements for the laboratory cabin inner. (a) measured strain, BHF=10ton (panel wrinkled); (b) measured strain, BHF=30ton (panel necked); (c) measured strain, BHF =50ton (panel fractured).Fig. 16. FEM strain predictions for the laboratory cabin inner. (a) Predicted strain, BHF=10ton; (b) predicted strain, BHF=30ton; (c) predicted strain, BHF=50ton.Fig. 17. Predicted effect of friction for the laboratory cabin inner, BHF=30ton. (a) Predicted strain, =0.06; (b) predicted strain, =0.10.A summary of the results of the comparisons is included in Table 3. This table shows that the simulations predicted the experimental observations at least as well as the strain measurement system at each of the experimental conditions. This indicates that Pam-Stamp can be used to assess formability issues associated with the die design.Table 3. Summary results of cabin inner study 4. Blank holder force control applicationsThe objective of this investigation was to determine the drawability of various, high performance materials using a hemispherical, dome-bottomed, deep drawn cup (see Fig. 18) and to investigate various time variable blank holder force profiles. The materials that were investigated included AKDQ steel, high strength steel, bake hard steel, and aluminum 6111 (see Table 4). Tensile tests were performed on these materials to determine flow stress and anisotropy characteristics for analysis and for input into the simulations (see Fig. 19 and Table 5).Fig. 18. Dome cup tooling geometry.Table 4. Material used for the dome cup study Fig. 19. Results of tensile tests of aluminum 6111, AKDQ, high strength, and bake hard steels. (a) Fractured tensile specimens; (b) Stress/strain curves.Table 5. Tensile test data for aluminum 6111, AKDQ, high strength, and bake hard steels It is interesting to note that the flow stress curves for bake hard steel and AKDQ steel were very similar except for a 5% reduction in elongation for bake hard. Although, the elongations for high strength steel and aluminum 6111 were similar, the n-value for aluminum 6111 was twice as large. Also, the r-value for AKDQ was much bigger than 1, while bake hard was nearly 1, and aluminum 6111 was much less than 1.The time variable BHF profiles used in this investigation included constant, linearly decreasing, and pulsating (see Fig. 20). The experimental conditions for AKDQ steel were simulated using the incremental code Pam-Stamp. Examples of wrinkled, fractured, and good laboratory cups are shown in Fig. 21 as well as an image of a simulated wrinkled cup.Fig. 20. BHF time-profiles used for the dome cup study. (a) Constant BHF; (b) ramp BHF; (c) pulsating BHF.Fig. 21. Experimental and simulated dome cups. (a) Experimental good cup; (b) experimental fractured cup; (c) experimental wrinkled cup; (d) simulated wrinkled cup.Limits of drawability were experimentally investigated using constant BHF. The results of this study are shown in Table 6. This table indicates that AKDQ had the largest drawability window while aluminum had the smallest and bake hard and high strength steels were in the middle. The strain distributions for constant, ramp, and pulsating BHF are compared experimentally in Fig. 22 and are compared with simulations in Fig. 23 for AKDQ. In both simulations and experiments, it was found that the ramp BHF trajectory improved the strain distribution the best. Not only were peak strains reduced by up to 5% thereby reducing the possibility of fracture, but low strain regions were increased. This improvement in strain distribution can increase product stiffness and strength, decrease springback and residual stresses, increase product quality and process robustness.Table 6. Limits of drawability for dome cup with constant BHF Fig. 22. Experimental effect of time variable BHF on engineering strain in an AKDQ steel dome cup.Fig. 23. Simulated effect of time variable BHF on true strain in an AKDQ steel dome cup.Pulsating BHF, at the frequency range investigated, was not found to have an effect on strain distribution. This was likely due to the fact the frequency of pulsation that was tested was only 1Hz. It is known from previous experiments of other researchers that proper frequencies range from 5 to 25Hz 3. A comparison of load-stroke curves from simulation and experiments are shown in Fig. 24 for AKDQ. Good agreement was found for the case where =0.08. This indicates that FEM simulations can be used to assess the formability improvements that can be obtained by using BHF control techniques.Fig. 24. Comparison of experimental and simulated load-stroke curves for an AKDQ steel dome cup.5 Conclusions and future work In this paper, we evaluated an improved design process for complex stampings which involved eliminating the soft tooling phase and incorporated the validation of product and process using one-step and incremental FEM simulations. Also, process improvements were proposed consisting of the implementation of blank holder force control to increase product quality and process robustness.Three separate investigations were summarized which analyzed various stages in the design process. First, the product design phase was investigated with a laboratory and industrial validation of the one-step FEM code FAST_FORM3D and its ability to assess formability issues involved in product design. FAST_FORM3D was successful at predicting optimal blank shapes for a rectangular pan and an industrial instrument cover. In the case of the instrument cover, many hours of trial and error experimentation could have been eliminated by using FAST_FORM3D and a better blank shape could have been developed.Second, the die design