六邊形墊片復(fù)合沖壓模設(shè)計(jì)【說(shuō)明書(shū)+CAD】

六邊形墊片復(fù)合沖壓模設(shè)計(jì)【說(shuō)明書(shū)+CAD】,說(shuō)明書(shū)+CAD,六邊形墊片復(fù)合沖壓模設(shè)計(jì)【說(shuō)明書(shū)+CAD】,六邊形,墊片,復(fù)合,沖壓,設(shè)計(jì),說(shuō)明書(shū),仿單,cad 六邊形墊片沖壓復(fù)合模模具設(shè)計(jì)專(zhuān)業(yè)：學(xué)生姓名：學(xué)生學(xué)號(hào)：指導(dǎo)教師：完成時(shí)間：目錄目錄2一、沖裁件的工藝分析3二、 沖壓工藝方案的確定4三、沖裁間隙5四、 凸模與凹模刃口尺寸的計(jì)算6（一） 凸、凹模刃口尺寸計(jì)算的基本原則6（二） 刃口尺寸計(jì)算方法6（三） 刃口尺寸計(jì)算9五、排樣設(shè)計(jì)10（一） 排樣形式的確定10（二） 條料寬度的確定11 (三) 材料利用率13六、沖裁力相關(guān)的計(jì)算14（一）沖裁力的計(jì)算14（二）總沖裁力、推料力、卸料力、頂件力和總沖壓力15（三）壓力機(jī)公稱(chēng)壓力的選取17七、模具壓力中心的確定19八、 模具總體設(shè)計(jì)20（一） 模具類(lèi)型的選擇20（二）定位方式的選擇201. 送進(jìn)導(dǎo)料方式的選擇202. 送料定距方式的選用213. 卸料、出件方式的選擇21九、沖模主要零件的設(shè)計(jì)22（一） 工作零件的設(shè)計(jì)221. 凸凹模的設(shè)計(jì)222. 沖孔凸模的設(shè)計(jì)233. 落料凹模的設(shè)計(jì)24（二） 卸料板的設(shè)計(jì)26（三） 定位零件的設(shè)計(jì)27（四） 模架及其它零件的設(shè)計(jì)28十、模具總裝圖29十一、結(jié)論31十二、致謝31參考文獻(xiàn)32一、沖裁件的工藝分析由零件圖11可知，該零件形狀簡(jiǎn)單、對(duì)稱(chēng)，是由圓弧和直線組成。沖裁件內(nèi)外形所能達(dá)到的精度要求不高為IT12。將以上精度與零件簡(jiǎn)圖中所標(biāo)注的尺寸公差相比較，可認(rèn)為該零件的精度要求能夠在沖裁加工中得到保證。其它尺寸標(biāo)注、生產(chǎn)批量等情況，也均符合沖裁的工藝要求，故決定采用沖裁落料復(fù)合模進(jìn)行加工，且一次沖壓成形。材料：08鋼具有良好的塑性、焊接性、可鍛性及良好的沖壓性能，常用來(lái)制造焊接結(jié)構(gòu)件和沖壓件。工件結(jié)構(gòu)形狀：沖裁件外形應(yīng)盡量避免有尖角，為了提高模具壽命，在所有60傾角改為R2的倒角。零件精度的選擇：本文所設(shè)計(jì)的沖裁零件是板件如圖1-1，該沖裁件的材料為08鋼，具有較好的可沖壓性能。該沖裁件的結(jié)構(gòu)較簡(jiǎn)單，比較適合沖裁，零件圖上所有尺寸均未注公差，屬于自由尺寸，可參考幾何量公差與檢測(cè)確定沖裁件公差等級(jí)，根據(jù)查表，該零件的公差等級(jí)取IT12級(jí)確定零件的尺寸公差。 圖1-1零件簡(jiǎn)圖 2、 沖壓工藝方案的確定該工件包括落料、沖孔兩個(gè)基本工序，可以有以下三種工藝方案：方案一：先落料，后沖孔，采用單工序模生產(chǎn)。方案二：沖孔落料復(fù)合沖壓，采用復(fù)合模生產(chǎn)。方案三：沖孔落料級(jí)進(jìn)沖壓。采用級(jí)進(jìn)模生產(chǎn)。方案一單工序沖裁模指在壓力機(jī)一次行程內(nèi)只完成一個(gè)沖壓工序的沖裁模。該模具結(jié)構(gòu)簡(jiǎn)單，但需要兩道工序兩副模具，成本高而生產(chǎn)效率低，難以滿(mǎn)足中批量生產(chǎn)的要求。方案二復(fù)合沖裁模是指在一次工作行程中，在模具同一部位同時(shí)完成數(shù)道沖壓工序的模具。該模具只需要一副模具，工件的精度及生產(chǎn)效率都很高，但工件最小壁厚2.0mm接近凸凹模許用最小壁厚2.2mm，模具強(qiáng)度較差，制造難度大，并且沖壓后成品件留在模具上，在清理模具上的物料時(shí)會(huì)影響沖壓速度，操作不方便。方案三級(jí)進(jìn)模：是指壓力機(jī)在一次行程中，依次在模具幾個(gè)不同的位置上同時(shí)完成多道沖壓工序的模具。它也只需要在一副模具內(nèi)可以完成多道不同的工序，可包括沖裁、彎曲、拉深等，具有比復(fù)合更好的生產(chǎn)效率。它的制件和廢料均可以實(shí)現(xiàn)自然漏料，所以操作安全、方便，易于實(shí)現(xiàn)自動(dòng)化。難以保證制件內(nèi)、外相對(duì)位置的準(zhǔn)確性因此制件精度不高。通過(guò)對(duì)上述三種方案的的分析比較，因?yàn)樵撝萍木纫蟛桓?，用于批量生產(chǎn)。所以該制件的沖壓生產(chǎn)采用方案二為佳。三、沖裁間隙1. 間隙對(duì)沖裁工作的影響間隙值影響到?jīng)_裁時(shí)彎曲、拉伸、擠壓等附加變形的的大小，因而對(duì)沖裁工序的影響大，主要有以下幾個(gè)方面： （1）間隙對(duì)零件質(zhì)量的影響 模具間隙是影響斷面質(zhì)量的主要因素，提高斷面質(zhì)量的關(guān)鍵在于推遲裂紋的產(chǎn)生，以增大光亮帶寬度，其主要途徑就是減小模具間隙。此外間隙又是影響尺寸精度的主要因素。 （2）間隙對(duì)沖裁力的影響 間隙越小，變形區(qū)內(nèi)壓應(yīng)力成分趟大，拉應(yīng)力成分越小，材料變形抗力增加，沖裁力就越大。反之，間隙越大，變形區(qū)內(nèi)拉應(yīng)力成分就越大，變形抗力降低，沖裁力就校間隙達(dá)材料厚的5%-20%時(shí)，沖裁力下降不明顯。當(dāng)單邊間隙Z增大到材料厚度的15%-20%時(shí)，卸料力為0。 （3）間隙對(duì)模具壽命的影響 由于工件與凸、凹模側(cè)壁之間有磨擦的存在，間隙小，磨擦大，模具壽命短。沖裁過(guò)程中，凸模與被沖孔之聞，凹模與落料件之閥均有摩擦，而且聞隙越小，摩擦越嚴(yán)重。所以過(guò)小的間隙對(duì)模具壽命極為不利，而較大的間隙可使凸模與凹模的側(cè)面與材料間的摩擦減小，井能減緩間隙不均勻的影響，從而提高模具的壽命。綜上所述，設(shè)計(jì)模具時(shí)一定要選擇合理的間隙，以保證沖裁件的斷面質(zhì)量、尺寸精度滿(mǎn)足產(chǎn)品的要求，所需沖裁力小、模具壽命高，但分別從質(zhì)量，沖裁力、模具壽命等方面的要求確定的合理間隙并不是同一個(gè)數(shù)值，只是彼此接近。考慮到制造中的偏差及使用中的磨損、生產(chǎn)中通常只選擇一個(gè)適當(dāng)?shù)姆秶鳛楹侠黹g隙，只要間隙在這個(gè)范圍內(nèi)，就可以沖出良好的制件，這個(gè)范圍的最小值稱(chēng)為最小合理間隙Zmin，最大值稱(chēng)為最大合理間隙Zmax。考慮到模具在使用過(guò)程中的磨損使間隙增大，故設(shè)計(jì)與制造新模具時(shí)要采用最小合理間隙值Zmin。確定凸凹模合理間隙有理論確定法和查表確定法。根據(jù)實(shí)用間隙表查得：材料08鋼的最小雙面間隙2Zmin=0.246mm，最大雙面間隙2Zmax=0.360mm,4、 凸模與凹模刃口尺寸的計(jì)算 凸凹模刃口尺寸精度決定的合理與否，直接影響沖裁件的尺寸精度及合理間隙值能否保證，也關(guān)系模具加工成本和壽命。因此，計(jì)算凹凸模刃口尺寸是一項(xiàng)重要工作。（1） 凸、凹模刃口尺寸計(jì)算的基本原則 計(jì)算沖裁凸凹模刃口尺寸的依據(jù)為1）沖裁變形規(guī)律，記落料件尺寸與凹模刃口尺寸相等，沖孔尺寸與凸模刃口尺寸相同2）零件的尺寸精度。3）合理的間隙值。4）磨損規(guī)律5）沖模的加工制造方法。因而在計(jì)算刃口尺寸時(shí)應(yīng)按下屬原則進(jìn)行 1.保證沖出合格的零件。 根據(jù)沖裁變形規(guī)律，沖孔尺寸等于凸模刃口尺寸，落料件尺寸等于凹模刃口尺寸。因而沖孔時(shí)，應(yīng)以凸模為基準(zhǔn)件。落料時(shí)應(yīng)以凹模為基準(zhǔn)件?；鶞?zhǔn)件的尺寸應(yīng)在零件的公差范圍內(nèi)。沖孔時(shí)間隙取在凹模上，落料時(shí)間隙取在凸模上。 2.保證模具具有一定的使用壽命。 新磨具的間隙應(yīng)是最小的合理間隙，磨損后達(dá)到最大合理間隙，考慮到?jīng)_裁時(shí)凸凹模的磨損，再設(shè)計(jì)凸凹模刃口尺寸時(shí)，對(duì)基件刃口尺寸在磨損后增大的，其刃口公稱(chēng)尺寸應(yīng)取工減尺寸范圍內(nèi)較小的數(shù)值。對(duì)基準(zhǔn)件刃口尺寸在磨損后減小的，其刃口公稱(chēng)尺寸應(yīng)取工件尺寸公差范圍內(nèi)較大的數(shù)值。 3.考慮沖模制造修理方便，降低成本。 為使新磨具的間隙值不小于最小合理間隙，一般凹模公差標(biāo)準(zhǔn)成，凸模公差標(biāo)注成。間隙能保證的條件下不要把制造公差定的太緊。一般模具制造精度比工件精度高24級(jí)。若零件沒(méi)有標(biāo)注公差，對(duì)于非緣形件按國(guó)家標(biāo)準(zhǔn)“非配合尺寸的公差數(shù)值”IT14精度處理，沖模則可按IT11級(jí)制造；對(duì)于圓形件，一般可按IT79級(jí)制造模具。沖壓件的尺寸公差應(yīng)按“入體”原則標(biāo)注為單向公差，落料件上偏差為零，下偏差為負(fù)；沖孔件上偏差為正，下偏差為零。 （二） 刃口尺寸計(jì)算方法由于模具的加工方法不同，凸模與凹模刃口部分尺寸的計(jì)算公式與制造公差的標(biāo)注也不同，刃口尺寸的計(jì)算方法可以分為兩種情況。1）凸模與凹模分開(kāi)加工。這種方法適用于圓形或簡(jiǎn)單規(guī)則形狀的沖裁件。2）凸模與凹模配合加工。對(duì)于形狀復(fù)雜或薄料的沖裁件的沖裁，為了保證凸凹模之間的間隙值，一般采用配合加工。 對(duì)該制件應(yīng)該選用凸模和凹模分別加工的方法，按圖紙加工之尺寸。要分別標(biāo)注凸模和凹模刃口尺寸和制造公差（凸模p、凹模d）。為了保證初始間隙值小于最大合理間隙2Zmin，必須滿(mǎn)足下列條件： p+d2Zmax-2Zmin 或取p=0.4(2Zmax-2Zmin) d=0.6(2Zmax-2Zmin)也就是說(shuō)，新制造的模具應(yīng)該是p+d+2Zmin2Zmax。否則制造的模具間隙已經(jīng)超過(guò)允許的變動(dòng)的范圍2CZax-2Zmin。下面對(duì)落料和沖孔兩種情況進(jìn)行討論。1、落料： 設(shè)工件的尺寸，根據(jù)計(jì)算原則,落料時(shí)以凹模為設(shè)計(jì)基準(zhǔn)。首先確定凹模尺寸,使凹?；境叽缃咏虻扔谥萍妮喞淖钚O限尺寸,再減小凸模尺寸以保證最小合理間隙值2Zmin。其計(jì)算公式如下： 2、沖孔：設(shè)沖孔尺寸為根據(jù)以上原則,沖孔時(shí)以凸模設(shè)計(jì)為基準(zhǔn),首先確定凸模刃口尺寸,使凸?；境叽缃咏虻扔诠ぜ椎淖畲髽O限尺寸,再增大凹模尺寸以保證最小合理間隙2Zmin。凸模制造偏差取負(fù)偏差，凹模取正偏差。其計(jì)算公式如下： 在同一工步中出制件兩個(gè)以上孔時(shí),凹模型孔中心距Ld 按下式確定: Ld=(Lmin+0.5)0.125式中Dd落料凹?；境叽?mm)；Dp落料凸?；境叽?mm)；D落料件最大極限尺寸(mm)；dd沖孔凹模基本尺寸(mm)；dp沖孔凸?；境叽?mm)；d沖孔件孔的最小極限尺寸(mm)；Ld同一工步中凹?？拙嗷境叽?mm)；Lmin制件孔距最小極限尺寸(mm)；制件公差(mm) 可查表41;2Zmin凸、凹模最小初始雙面間隙(mm)；d凸模下偏差,可按IT6選用(mm)；p凹模上偏差,可按IT7選用(mm)；X 磨損系數(shù),當(dāng)制件公差為IT10以上,取X=1；當(dāng)工件公差為IT11IT13,取X=0.75；當(dāng)工件差為IT14者,取X=0.5。表4-1標(biāo)準(zhǔn)公差數(shù)值公差等級(jí)IT12IT13IT14IT15IT16IT17IT18基本尺寸/mm/mm3366101018183030505080801201201801802502503153154004005000.10.120.150.180.210.250.30.350.40.460.520.570.630.140.180.220.270.330.390.460.540.630.720.810.890.970.250.30.360.430.520.620.740.871.01.151.31.41.550.40.480.580.70.841.01.21.41.61.852.12.32.50.60.750.91.11.316.019.02.22.52.93.23.64.011.21.51.82.12.53.03.54.04.65.25.76.31.41.82.22.73.33.94.65.46.37.28.18.99.7（3） 刃口尺寸計(jì)算根據(jù)計(jì)算原則,落料時(shí)以凹模為設(shè)計(jì)基準(zhǔn)。首先確定凹模尺寸,使凹?；境叽缃咏虻扔谥萍妮喞淖钚O限尺寸,再減小凸模尺寸以保證最小合理間隙值2Zmin。 校核 p+d2Zmax-2Zmin 0.016+0.025 0.360-0.246 0.041 0.114（滿(mǎn)足間隙要求）根據(jù)計(jì)算原則,沖孔時(shí)以凸模設(shè)計(jì)為基準(zhǔn),首先確定凸模刃口尺寸,使凸模基本尺寸接近或等于工件孔的最大極限尺寸,再增大凹模尺寸以保證最小合理間隙2Zmin。 校核 p+d2Zmax-2Zmin 0.013+0.021 0.360-0.246 0.034 0.114在同一工步中出制件兩個(gè)以上孔時(shí),凹模型孔中心距Ld 按下式確定: Ld=(Lmin+0.5)0.125 =(40+0.50.39) 0.1250.39 =40.1950.049五、排樣設(shè)計(jì)（一） 排樣形式的確定1.排樣的分類(lèi)1）按材料利用情況分類(lèi)1 有廢料排樣 沿零件全部外形沖裁，零件周邊都有生料。2 少?gòu)U料排樣 沿零件部分外形切斷或沖裁，只局部又生料。3 無(wú)廢料排樣 除料頭料尾外無(wú)任何生料。2） 安沖裁件在條料上的布置防水，排樣又可分為 直排、單排、多排、斜排、對(duì)排、混合排、少?gòu)U料、無(wú)廢料、裁搭邊等。 此處選用如圖5-1所示排樣方式 搭邊值、條料寬度的確定 2. 搭邊值的確定排樣時(shí)零件之間以及零件與條料側(cè)邊間留下的工藝余料，稱(chēng)為搭邊。搭邊的作用是補(bǔ)償定位誤差，保持條料有一定的剛度，以保證零件質(zhì)量和送料方便。搭邊過(guò)大，浪費(fèi)材料、搭邊過(guò)小，沖裁時(shí)容易翹曲或被拉斷，不僅會(huì)增大沖件毛刺，有時(shí)還有拉入凸、凹模間隙中損壞模具刃口，降低模具壽命或影響送料工作。圖5-1 排樣圖搭邊值通常由經(jīng)驗(yàn)確定，表所列搭邊值為普通沖裁時(shí)經(jīng)驗(yàn)數(shù)據(jù)之一。表5-1 搭邊a和a1數(shù)值材料厚度圓件及r2t的工件矩形工件邊長(zhǎng)L50mm矩形工件邊長(zhǎng)L50mm或r2t的工件工件間a側(cè)面a1工件間a側(cè)面a1工件間a側(cè)面a10.250.250.50.50.80.81.21.21.61.62.02.02.52.53.03.03.53.54.04.05.05.0121.81.21.00.81.01.21.51.82.22.53.00.6t2.01.51.21.01.21.51.82.22.52.83.50.7t2.21.81.51.21.51.82.02.22.52.53.50.7t2.52.01.81.51.82.02.22.52.83.24.00.8t2.82.21.81.51.82.02.22.52.83.24.00.8t3.02.52.01.82.02.22.52.83.23.54.50.9t根據(jù)制件厚度與制件的排樣方法可以查表51得：搭邊值工件間a為2.0mm 側(cè)面a1 為2.2mm（二） 條料寬度的確定排樣方式和搭邊值確定以后，條料的寬度和進(jìn)距也就可以設(shè)計(jì)出。確定1條料寬度的原則是：最小條料寬度要保證沖裁時(shí)零件周?chē)凶銐虻拇钸呏?；最大條料寬度能在導(dǎo)料板間送進(jìn)，并與導(dǎo)料板間有一定的間隙。條料寬度的大小還與模具是否有側(cè)壓裝置或側(cè)刃有關(guān)。計(jì)算條料寬度有三種情況需要考慮：1、有側(cè)壓裝置時(shí)條料的寬度。2、無(wú)側(cè)壓裝置時(shí)條料的寬度。3、有定距側(cè)刃時(shí)條料的寬度。該零件采用無(wú)側(cè)壓裝置的模具，其條料寬度應(yīng)考慮在送料過(guò)程中因條料的擺動(dòng)而使側(cè)面搭邊減少。為了補(bǔ)償面搭邊的減少部分，條料寬度應(yīng)增加一個(gè)條料的擺動(dòng)量。故條料寬度為： （5-1）導(dǎo)尺間距 (5-2)式中：B條料寬度的基本尺寸；D條料寬度方向沖裁件的最大尺寸；a側(cè)搭邊值。c1條料與導(dǎo)料板之間的間隙（即條料的可能擺動(dòng)量）：B100, c1=0.51.0; B100, c1=1.01.5.表5-2 剪料公差及條料與導(dǎo)料板之間隙（mm)條料寬度B/mm材料厚度t/mm112233550501001001501502202203000.40.50.60.70.80.50.60.70.80.90.70.80.91.01.10.91.01.11.21.3導(dǎo)料板之間的距離，應(yīng)使條料與導(dǎo)料板之間保持一定的間隙查表53，以保證送料暢通。表5-3 條料寬度偏差（mm）條料寬度B|mm材料厚度0.50.5112200.050.080.120300.080.10.1530500.10.150.2D取值由設(shè)計(jì)條料寬度方向沖裁件的最大尺寸為50 (mm)側(cè)搭邊值a可以從表51中查出為2.2 (mm)條料與導(dǎo)料板之間的間隙c1取查表52可得條料寬度偏差下偏差為0.8(mm)故帶入條料寬度公式得； =50+2（2.2+0.8）+0.5=56.5(mm)(三) 材料利用率 材料利用率通常以一個(gè)進(jìn)距內(nèi)制件的實(shí)際面積與所用毛坯面積的百分率表示；=(nA1/hB)100% （3-2）式中 材料利用率（%）；n 沖裁件的數(shù)目；A1 沖裁件的實(shí)際面積(mm2)；B 板料寬度(mm)；h進(jìn)距；計(jì)算沖壓件的面積；A1=2521.653-3.141515 =1834(mm2)條料寬度計(jì)算：B=50+22.2=54.4 (mm)送進(jìn)距離計(jì)算：h=43.3+2=45.3 (mm)一個(gè)進(jìn)距的材料利用率；=(nA1/hB)100% =11834(45.354.4)100%=74.42%由此可之，值越大，材料的利用率就越高，廢料越少。工藝廢料的多少?zèng)Q定于搭邊和余量的大小，也決定于排樣的形式和沖壓方式。因此，要提高材料利用率，就要合理排樣，減少工藝廢料。六、沖裁力相關(guān)的計(jì)算（一）沖裁力的計(jì)算沖裁力是沖裁過(guò)程中凸模對(duì)材料的壓力。沖裁力是選用壓力機(jī)、模具設(shè)計(jì)以及強(qiáng)度校核的重要依據(jù)。沖裁在理論上可以近似認(rèn)為是剪切斷裂，所以最大沖裁力可以按板料的抗剪強(qiáng)度來(lái)計(jì)算。普通平刃沖裁模，其沖裁力F p一般可以按下式計(jì)算： 式中 材料抗剪強(qiáng)度，見(jiàn)附表（MPa）； L零件剪切周長(zhǎng)（mm）； t材料厚度（mm） K-系數(shù)系數(shù)K是考慮到?jīng)_裁模刃口的磨損，凸模與凹模間隙之波動(dòng)（數(shù)值的變化或分布不均），潤(rùn)滑情況，材料力學(xué)性能與厚度公差的變化等因數(shù)而設(shè)置的安全系數(shù)K，一般取1.3。為了簡(jiǎn)便，也可用材料的抗拉強(qiáng)度，按下式估算沖裁力：表61常用沖壓材料的力學(xué)性能材料名稱(chēng)牌號(hào)材料狀態(tài)抗剪強(qiáng)度抗拉強(qiáng)度申長(zhǎng)率屈服強(qiáng)度電工用純鐵C0.025DT1、DT2、DT3已退火18023026普通碳素鋼Q195火未退2603203204002833200Q2353103803804702125240Q2754005005006201519280優(yōu)質(zhì)碳素結(jié)構(gòu)鋼08F已退火22031028039032180082603603304503220010260340300440292102028040036051025250454405605507001636065Mn60075012400不銹鋼1Cr13已退火600400470211Cr18Ni9Ti熱處理退軟32038054070040200鋁L2、L3、L5已退火8075110255080冷作硬化1001201504鋁錳合金LF21已退火701101101451950硬鋁LY12已退火10515015021512淬硬后冷作硬化28032040060010340純銅T1、T2、T3軟態(tài)1602003007硬態(tài)2403003黃銅H62軟態(tài)26030035半硬態(tài)30038020200H68軟態(tài)24030040100半硬態(tài)28035025由于材料08鋼的力學(xué)性能查（表61）可得：抗剪強(qiáng)度=260360，故取起抗拉強(qiáng)度b代替抗剪強(qiáng)度，查表可知b=360(MPa)。（二）總沖裁力、推料力、卸料力、頂件力和總沖壓力由于沖裁模具采用彈性卸料裝置和上出件方式。 F總沖壓力。 Fp總沖裁力。 FQ卸料力 FQ1推料力。 FQ2頂件力計(jì)算總沖裁力 Fp=F1+F2 F1落料時(shí)的沖裁力。 F2沖孔時(shí)的沖裁力。沖裁周邊的總長(zhǎng)（mm）落料周長(zhǎng)為： L2=256 =150 （mm）沖孔周長(zhǎng)為： L1=3.1430 =94.2（mm）落料沖裁力為： F1=KtL2 =1.31503602 =140400 (N)沖孔沖裁力為： F2=KtL1 =1.3294.2360 = 88171.2 (N)所以可求總沖裁力為： Fp=F1+F2 =140400+88171.2 =228571.2（N）表6-2 卸料力、推件力和頂件力系數(shù)料厚t/mmKxKtKd鋼0.10.10.50.52.52.56.56.50.0650.0750.0450.0550.040.050.030.040.020.030.10.0630.0550.0450.0250.140.080.060.050.03鋁、鋁合金純銅，黃銅0.0250.080.020.060.030.070.030.09按卸料力公式計(jì)算卸料力FQFQ=KxFp查表62得Kx=0.04根據(jù)公式得FQ=KxFp=0.04228571.2=9142.848 (N)按推料力公式計(jì)算推料力FQ1 FQ1=nKtFp取n=2查表62得Kt=0.055n梗塞在凹模內(nèi)的制件或度料數(shù)量（n=h/t h直刃口部分的高度，t材料厚度）根據(jù)公式得 FQ1=nKtFp =20.055228571.2 =25142.832按頂件力公式算頂件力FQ2FQ2=KdFpKd查表62得0.06根據(jù)公式得FQ2=KdFp=0.06228571.2 =13714.272 （N）（三）壓力機(jī)公稱(chēng)壓力的選取 沖裁時(shí)，壓力機(jī)的公稱(chēng)壓力必須大于或等于沖裁各工藝力的總和。采用彈壓卸料裝置和上出件的模具表63 常用冷沖壓設(shè)備的工作原理和特點(diǎn)類(lèi)型設(shè)備名稱(chēng)工作原理特點(diǎn)機(jī)械式壓力機(jī)摩擦壓力機(jī)利用摩擦盤(pán)與飛輪之間相互接觸傳遞動(dòng)力，皆助螺桿與螺母相對(duì)運(yùn)動(dòng)原理而工作。結(jié)構(gòu)簡(jiǎn)單，當(dāng)超負(fù)荷時(shí)，只會(huì)引起飛輪與摩擦盤(pán)之間的滑動(dòng)，而不致?lián)p壞機(jī)件。但飛輪輪緣摩擦損壞大，生產(chǎn)率低。適用于中小件的沖壓加工，對(duì)于校正、亞印和成形等沖壓工序尤為適宜。曲柄式壓力機(jī)利用曲柄連桿機(jī)構(gòu)進(jìn)行工作，電機(jī)通過(guò)皮帶輪及齒輪帶動(dòng)曲軸傳動(dòng)，經(jīng)連桿使滑塊作直線往復(fù)運(yùn)動(dòng)。曲柄壓力機(jī)分為偏心壓力機(jī)和曲軸壓力機(jī)，二者區(qū)別主要在主軸，前者主軸是偏心軸，后者主軸是曲軸。偏心壓力機(jī)一般是開(kāi)式壓力機(jī)，而曲軸壓力機(jī)有開(kāi)式和閉式之分。生產(chǎn)率高，適用于各類(lèi)沖壓加工。高速壓力機(jī)工作原理與曲柄壓力機(jī)相同，但其剛度、精度、行程次數(shù)都比較高，一般帶有自動(dòng)送料裝置、安全檢測(cè)裝置等輔助裝置。生產(chǎn)率很高，適用于大批量生產(chǎn)，模具一般采用多工為級(jí)進(jìn)模。液壓機(jī)油壓機(jī)水壓機(jī)利用帕斯卡原理，以水或油為工作介質(zhì)，采用靜壓 力傳遞進(jìn)行工作，使滑塊上、下往復(fù)運(yùn)動(dòng)。壓力大，而且是靜壓力，但生產(chǎn)率低。適用于拉深、擠壓等成形工序。根據(jù)公式得 F=Fp+FQ+FQ2 =228571.2 +25142.832+13714.272 =267428.304 (N)沖壓設(shè)備屬鍛壓機(jī)械。常見(jiàn)的冷沖壓設(shè)備有機(jī)械壓力機(jī)（以Jxx表示其型號(hào)）和液壓機(jī)（以Yxx表示其型號(hào)）。沖壓設(shè)備分類(lèi)：1、 機(jī)械壓力機(jī)按驅(qū)動(dòng)滑塊機(jī)構(gòu)的種類(lèi)可以分為曲柄式和摩擦式；2、 按滑塊個(gè)數(shù)可分為單動(dòng)和雙動(dòng)；3、 按床身機(jī)構(gòu)形式可分為開(kāi)式（C型床身）和閉式（型床身）；4、 按自動(dòng)化程度可分為普通壓力機(jī)和高速壓力機(jī)等；常用冷沖壓設(shè)備的工作原理和特點(diǎn)如表63根據(jù)綜上所計(jì)算出來(lái)的總壓力與常用冷沖壓設(shè)備的工作原理和特點(diǎn)選取開(kāi)式可傾壓力機(jī)型號(hào)為J2335。七、模具壓力中心的確定模具壓力中心是指沖壓時(shí)諸沖壓力合力的作用點(diǎn)位置。為了確保壓力機(jī)和模具正常工作，應(yīng)使模具的壓力中心與壓力機(jī)滑塊的中心相重合，否則，會(huì)使沖模和力機(jī)滑塊產(chǎn)生偏心載荷，使滑塊和導(dǎo)軌之間產(chǎn)生過(guò)大的摩擦，模具導(dǎo)向零件加速磨損，降低模具和壓力機(jī)的使用壽命。沖裁模的壓力中心，可按下述原則來(lái)確定：1、對(duì)稱(chēng)形狀的單個(gè)沖裁件，沖模的壓力中心就是沖裁件的幾何中心。2、工件形狀相同且分布位置對(duì)稱(chēng)時(shí)，沖模的壓力中心與零件的對(duì)稱(chēng)中心相重合。3、形狀復(fù)雜的零件、多孔沖模、級(jí)進(jìn)模的壓力中心可用解析計(jì)算法求出沖模的對(duì)稱(chēng)中心。根據(jù)制件圖可以得出該工件形狀相同且分布位置對(duì)稱(chēng)，所以沖模的壓力中心與零件的對(duì)稱(chēng)中心相重合。7-1 制件圖紙八、 模具總體設(shè)計(jì)（一） 模具類(lèi)型的選擇由沖壓工藝分析可知，采用復(fù)合沖壓，所以模具類(lèi)型為復(fù)合模。（二）定位方式的選擇為保證沖裁出外形完整的合格零件。毛坯在模具中應(yīng)該有正確的位置。正確位置是依靠定位零件來(lái)保證的。由于毛坯形式和模具結(jié)構(gòu)不同，所以定位零件的種類(lèi)很多。設(shè)計(jì)時(shí)應(yīng)根據(jù)毛坯形式、模具結(jié)構(gòu)、零件公差大小、生產(chǎn)效率等進(jìn)行選擇。定位包括控制送料進(jìn)距的擋料和送料定距的擋料。 1. 送進(jìn)導(dǎo)料方式的選擇送進(jìn)導(dǎo)向方式有兩種，在此我們選擇復(fù)合模設(shè)計(jì)中最常用的一種，導(dǎo)料銷(xiāo)導(dǎo)向，在模具中設(shè)計(jì)兩個(gè)導(dǎo)料銷(xiāo)，并位于條料的兩側(cè)，該模具是從右向左送料，所以導(dǎo)料銷(xiāo)裝在前后各一側(cè)。形式為固定導(dǎo)料銷(xiāo)。如圖81所示。 圖8-1 固定導(dǎo)料銷(xiāo) 2. 送料定距方式的選用限位銷(xiāo)用來(lái)限制條料送進(jìn)的距離，在此我們根據(jù)國(guó)家標(biāo)準(zhǔn)選用活動(dòng)擋料銷(xiāo)如圖8-2 所示，其結(jié)構(gòu)簡(jiǎn)單、制造容易，用途廣泛。 圖8-2 活動(dòng)擋料銷(xiāo) 3. 卸料、出件方式的選擇 卸料零件的目的，是將沖裁后卡箍在凸模上或凸凹模上的制件或廢料卸掉，保證下次沖壓壓正常進(jìn)行。常用的卸料方式有剛性卸料和彈性卸料兩種。 因?yàn)楣ぜ虾駷?mm，相對(duì)較薄，卸料力也比較小，故可采用彈性卸料。又因?yàn)槭菑?fù)合模生產(chǎn)，所以采用上出件比較便于操作與提高生產(chǎn)效率。 4. 標(biāo)準(zhǔn)模架導(dǎo)向方式的選擇按導(dǎo)柱在模架上的固定位置不同，導(dǎo)柱模架的基本型式有四種：對(duì)角導(dǎo)柱模架；后側(cè)導(dǎo)柱模架；中間導(dǎo)柱模架；四導(dǎo)柱模架。為了提高模具壽命和工件質(zhì)量，方便安裝調(diào)整，該復(fù)合模采用后側(cè)導(dǎo)柱的導(dǎo)向方式。九、沖模主要零件的設(shè)計(jì)設(shè)計(jì)主要零部件時(shí)，首先要考慮主要零部件用什么方法加工制造及總體裝配方法。結(jié)合模具的特點(diǎn)，本模具適宜采用線切割加工凸模固定板、卸料板、凸凹固定板、凹模及沖孔凸模、凸凹模。除凸凹模外，在采用線切割后，還得采用數(shù)控車(chē)床加工其形腔錐度。這種加工方法可以保證這些零件各個(gè)內(nèi)孔的同軸度，使裝配工作簡(jiǎn)化。下面就分別介紹各個(gè)零部件的設(shè)計(jì)方法。 （1） 工作零件的設(shè)計(jì) 1.凸凹模的設(shè)計(jì)因?yàn)樵撝萍螤顝?fù)雜，所以將落料凸模與沖孔凹模設(shè)計(jì)成一個(gè)整體為凸凹模。直通式凸模工作部分和固定部分的形狀做成一樣，直通式凸模采用線切割機(jī)床加工。凹模和工作部分與凸模聯(lián)在一起，為保證廢料直接由凸模從凸凹模內(nèi)孔推出。凹模洞口若采用直刃、則模內(nèi)有積薦廢料，脹力較大。若采用上直下斜的錐面式，可以解出積薦廢料的問(wèn)題，錐度先采用線切割加工后采用數(shù)控車(chē)床加工。通過(guò)固定板把凸凹模固定。固定板與凸凹模的配合按H7/m6。凸凹模材料應(yīng)選T10A，熱處理5860HRC，凸凹模與卸料板之間的間隙見(jiàn)表91查得凸凹模與卸料板的間隙選為0.035mm。凸凹模高度是固定板、卸料板和彈簧間隙組成。凸凹模高度為： H=H1+H2+（1520）mm H1固定板厚度；得H1=0.8H凹=0.816=12.8 mm(標(biāo)準(zhǔn)為15mm) H2卸料板厚度；查表94得H2=10 mm(1520)附加長(zhǎng)度，包括凸凹模的修磨量，凸模進(jìn)入凹模的深度及固定板與卸料板間的安全距離。（附加長(zhǎng)度取18）H=15+10+18 =43 mm 表9-1 凸凹模與卸料板、導(dǎo)柱與導(dǎo)套的間隙序號(hào)模具沖裁間隙Z卸料板與凸模間隙Z1輔助小導(dǎo)柱與小導(dǎo)套間隙Z210.0150.0250.0050.007約為0.00320.0250.050.0070.015約為0.00630.050.100.0150.025約為0.0140.100.150.0250.035約為0.02 2. 沖孔凸模的設(shè)計(jì)因?yàn)闆_孔凸模是由圓和非圓組合而成的凸模，結(jié)構(gòu)復(fù)雜，對(duì)模具零件精度要求較高；模具裝配精度也較高。將沖孔凸模設(shè)計(jì)成直通式，采用線切割加工。沖孔凸模與凸凹模中的落料凹模鑲拼結(jié)構(gòu)中的壓入式固定。凸模的高度是凸模固定板、凹模及附加長(zhǎng)度組成。凸模高度為： H=H1+H2+（1520）mm H1凸模固定板厚度；得H1=0.8H凹=0.816=12.8 mm(標(biāo)準(zhǔn)為15mm) H2凹模厚度； H2=16 mm(1520)附加長(zhǎng)度，包括凸凹模的修磨量，凸模進(jìn)入凹模的深度及固定板與卸料板間的安全距離。（附加長(zhǎng)度取18）H=15+16+18 =49 mm 3. 落料凹模的設(shè)計(jì)凹模采用整體凹模，各種沖裁的凹?？拙捎镁€切割機(jī)床加工，安排凹模在模架上位置時(shí)，要依據(jù)計(jì)算壓力中心的數(shù)據(jù)，將壓力中心與模柄中心重合。模具的外形尺寸如下： 模具厚度的確定公式為： H=Kb式中：K92系數(shù)值，考慮板料厚度的影響；b 沖裁件的最大外形尺寸；表9-2系數(shù)值Ks/mm材料厚度t/mm1336501001002002000.300.400.200.300.150.200.100.150.350.500.220.350.180.220.120.180.450.600.300.450.220.300.150.22查表92得：K=0.30 H=0.3050 =15 mm查表取標(biāo)準(zhǔn)：H=16 mm模具壁厚的確定公式為： C=(1.52)H =1.520216 =3032 mm凹模壁厚取C=32 mm、凹模寬度的確定公式為： B=b+2C =44+232 =108 mm查表取標(biāo)準(zhǔn)取B=125 mm凹模長(zhǎng)度的確定公式為： L=50+232 =114 mm凹模的長(zhǎng)度要考慮導(dǎo)料板發(fā)揮的作用，保證送料粗定位精度。查表取標(biāo)準(zhǔn)L=125 mm。凹模輪廓尺寸為125mm125mm16mm。凹模材料選用T10A，熱處理6062HRC。（二） 卸料板的設(shè)計(jì)卸料板不僅有卸料作用，還具有用外形凸模導(dǎo)向，對(duì)內(nèi)孔凸模起保護(hù)作用，卸料板的邊界尺寸與凹模的邊界尺寸相同，卸料板的厚度按表94選擇，卸料板厚度為10mm。卸料板與2個(gè)凸模的間隙以在凸模設(shè)計(jì)中確定了為0.035。卸料板上設(shè)置了4個(gè)螺釘。卸料板采用45鋼制造，熱處理淬火硬度4045HRC。表9-4固定卸料板厚度沖件厚度t卸料板寬度2000.866810120.81.5681012141.53810121416（三） 定位零件的設(shè)計(jì) 為了保證模具的正常工作和沖出合格的沖裁件，必須保證坯料或工序件對(duì)模具的工作刃口處于正確的相對(duì)位置，即必須定位。而模具送料平面中必須有兩個(gè)方向的限位：一是送料方向垂直的方向上限位，保證條料沿正確的方向的送進(jìn)，稱(chēng)為送進(jìn)的導(dǎo)向，二是在送進(jìn)方向上的限位，控制條料一次送進(jìn)的距離(步距)稱(chēng)為送料定距。屬于送料導(dǎo)向的定位零件有導(dǎo)料銷(xiāo)，導(dǎo)料板、側(cè)壓板等，屬于送料定距的定位零件有固定擋料銷(xiāo)、始用擋料銷(xiāo)、活動(dòng)擋料銷(xiāo)、導(dǎo)正銷(xiāo)、側(cè)刃等。屬于塊料或工序件的定位零件有定位銷(xiāo)、定位板等。由于止動(dòng)墊圈沖壓所用的材料屬于條料，厚度不大，零件精度且采用的是復(fù)合模進(jìn)行沖裁。終上所述定位零件選用導(dǎo)料銷(xiāo)，定位零件采用活動(dòng)擋料銷(xiāo)?；顒?dòng)擋料銷(xiāo)的位置可以由公式確定B=A-D/2+d/2 式中A送料進(jìn)距（mm）；d擋料銷(xiāo)直徑（mm）；D落料凸模直徑（mm）。B= A-D/2+d/2 =45.3-50/2+8/2 =24.3 (mm)（四） 模架及其它零件的設(shè)計(jì) 根據(jù)國(guó)家標(biāo)準(zhǔn),模架主要有兩大類(lèi),一類(lèi)是由上模座、下模座、導(dǎo)柱、導(dǎo)套組成的導(dǎo)柱模模架。另一類(lèi)是由彈壓導(dǎo)板、下模座、導(dǎo)柱、導(dǎo)套組成的導(dǎo)板模模架?？紤]到經(jīng)濟(jì)效益以及加工的特點(diǎn)，選擇后側(cè)導(dǎo)柱模模架。本模具采用滑動(dòng)導(dǎo)柱、導(dǎo)套來(lái)保證模具上、下模的精確導(dǎo)向?；瑒?dòng)導(dǎo)柱、導(dǎo)套都是圓柱形的，其加工方便，可采用車(chē)床加工，裝配容易。導(dǎo)柱的長(zhǎng)度應(yīng)保證上模座最底位置時(shí)（閉合狀態(tài)），導(dǎo)柱上端面與上模座頂面的距離15mm。而下模座底面與導(dǎo)柱底面的距離為5mm。導(dǎo)柱的下部與下模座導(dǎo)柱孔采用R7/h5的過(guò)盈配合,導(dǎo)套的外徑與上模座導(dǎo)套孔采用R7/h5的過(guò)盈配合。導(dǎo)套的長(zhǎng)度，需要保證沖壓時(shí)導(dǎo)柱一定要進(jìn)入導(dǎo)套10mm以上。導(dǎo)柱與導(dǎo)套之間采用H7/h6的間隙配合，導(dǎo)柱與導(dǎo)套均采用20鋼，熱處理硬度滲碳淬硬5660HRC。導(dǎo)柱的直徑、長(zhǎng)度，按標(biāo)準(zhǔn)選取。導(dǎo)柱：d/mmL/mm分別為32160；導(dǎo)套：d/mmL/mmDmm分別為3210545模座的的尺寸L/mmB/mm為160mm315mm。模座的厚度應(yīng)為凹模厚度的1.52倍上模座的厚度為30mm，上墊板厚度取8mm，凸凹固定板厚度取20mm，下模座的厚度為40mm。那么該模具的閉合高度為： H閉=H上模+H墊+H凸+H凸凹+H下模-h2式中： H凸凸模長(zhǎng)度，L=49 mm H凸凹凸凹模厚度，H=43 mmh2凸模沖裁后進(jìn)入凹模的深度，h2=3 mm H閉=H上模+H墊+H凸+H凸凹+H下模-h2 =32+8+49+43+45-3 =174 mm可見(jiàn)該模具閉合高度小于所選壓力機(jī)J2335的最大裝模高度（220mm）可以使用。十、模具總裝圖通過(guò)以上的設(shè)計(jì)，可得到模具總裝圖。模具的上模部分由上模座、上模墊板、凸模、凸模固定板及凹模等組成。上模座、上模墊板、凸模、凸模固定板及凹模用4個(gè)M10螺釘和2個(gè)8圓柱銷(xiāo)固定。螺釘選取：M1070mm的標(biāo)準(zhǔn)件。采用45鋼，熱處理淬火硬度4348HRC。圓柱銷(xiāo)選?。?70mm的標(biāo)準(zhǔn)件。采用45鋼，熱處理淬火硬度4348HRC。下模部分由下模座、凸凹模、卸料板及固定板等組成。下模座、凸凹模、卸料板及固定板用4個(gè)M10的螺釘和2個(gè)8的圓柱銷(xiāo)固定。螺釘選?。篗1070mm的標(biāo)準(zhǔn)件。采用45鋼，熱處理淬火硬度4348HRC。圓柱銷(xiāo)選?。?70mm的標(biāo)準(zhǔn)件。采用45鋼，熱處理淬火硬度4348HRC。沖孔廢料由凸凹模的沖孔凹模漏料孔漏出。十一、壓力機(jī)設(shè)備的選定通過(guò)校核，選擇開(kāi)式雙柱可傾壓力機(jī)J2335能夠滿(mǎn)足使用要求。其主要技術(shù)參數(shù)如下：公稱(chēng)壓力：350KN；滑塊行程：80mm； 最大閉合高度：270mm；最大裝模高度；220mm；作臺(tái)尺寸（前后左右）：370mm560mm；墊板尺寸（厚度孔徑）：50mm200mm；模柄孔尺寸：40mm60mm；最大傾角高度：30。12、 結(jié)論通過(guò)這次畢業(yè)設(shè)計(jì)我收獲頗多，指導(dǎo)老師的熱心指導(dǎo)，耐心的為我講解、分析，在設(shè)計(jì)的過(guò)程中所遇到的問(wèn)題，同學(xué)們的熱心幫助也讓我感到了同學(xué)之間的情誼。這次從設(shè)計(jì)過(guò)程、加工過(guò)程和零件的加工分析過(guò)程，其實(shí)也是考驗(yàn)我大學(xué)來(lái)理論知識(shí)的掌握、實(shí)際操作和如何將書(shū)本上的理論知識(shí)怎么樣運(yùn)用到實(shí)際操作的一個(gè)過(guò)程。在畢業(yè)設(shè)計(jì)過(guò)程中我掌握了很多東西，沖裁件的工藝分析，制件的排樣方法，沖裁力的相關(guān)計(jì)算，模具壓力中心的計(jì)算，沖裁間隙的確定，凸模與凹模刃口尺寸的計(jì)算，模具的總體設(shè)計(jì)，主要零部件的設(shè)計(jì)，壓力機(jī)的選擇，總裝配圖的繪制等?？傊?，通過(guò)這次畢業(yè)設(shè)計(jì)讓我掌握了很多東西，也有很多不足的地方，設(shè)計(jì)說(shuō)明書(shū)格式的不太清楚，模具的公差不好給，圖紙的繪制不熟練，但在老師和同學(xué)的幫助下我順利的完成了設(shè)計(jì)。通過(guò)這次設(shè)計(jì)我讓我全方位的知道模具的設(shè)計(jì)過(guò)程，真是受益匪淺。13、 致謝 本次課程設(shè)計(jì)離不開(kāi)兩位指導(dǎo)老師的幫助，老師總是耐心幫我看圖，幫我指正，向我發(fā)送郵件，傳達(dá)需要修改的地方和解決方案。感謝老師給我們這樣一次機(jī)會(huì)，能夠獨(dú)立地完成一個(gè)課程設(shè)計(jì)，并在這個(gè)過(guò)程當(dāng)中，給我們提供了許多相關(guān)資料，使我們?cè)诩磳㈦x校的最后一段時(shí)間里，能夠更多學(xué)習(xí)一些實(shí)踐應(yīng)用知識(shí)，增強(qiáng)了我們實(shí)踐操作和動(dòng)手應(yīng)用能力，提高了獨(dú)立思考的能力。為了順利幫我們完成課程設(shè)計(jì)，程老師披星戴月為我們修改作業(yè)，好感動(dòng)。再一次對(duì)我們的程老師表示感謝。感謝在整個(gè)課程設(shè)計(jì)期間陪伴我的小伙伴，和曾經(jīng)在各個(gè)方面給予過(guò)我?guī)椭耐瑢W(xué)們，在大學(xué)生活即將結(jié)束的最后的日子里，我們把一個(gè)龐大的，從來(lái)沒(méi)有上手的課題，圓滿(mǎn)地完成了。正是因?yàn)橛辛四銈兊膸椭抛屛也粌H學(xué)到了本次課題所涉及的新知識(shí)，更讓我感覺(jué)到了知識(shí)以外的東西。最后，感謝所有在本次課程設(shè)計(jì)中給予過(guò)我?guī)椭娜?。參考文獻(xiàn) 1 郝濱海.沖壓模具簡(jiǎn)明設(shè)計(jì)手冊(cè).化學(xué)工業(yè)出版社.2 楊可楨、程光蘊(yùn)、李仲生.機(jī)械設(shè)計(jì)基礎(chǔ).高等教育出版社3 機(jī)械制圖. 高等教育出版社。4 翁其金.沖壓工藝與沖模設(shè)計(jì).清華大學(xué)出版社.5 沖模設(shè)計(jì)與制造實(shí)用計(jì)算手冊(cè).機(jī)械工業(yè)出版社.6 高錦張.塑性成形工藝與模具設(shè)計(jì).機(jī)械工業(yè)出版社7 甘永立.幾何量公差與檢測(cè).上?？茖W(xué)技術(shù)出版社.8 齊衛(wèi)東.冷沖壓模具圖集.北京理工大學(xué)出版社9 史鐵梁.冷沖模設(shè)計(jì)指導(dǎo).機(jī)械工業(yè)出版社.10 張鼎承.沖模設(shè)計(jì)手冊(cè).北京.機(jī)械工業(yè)出版社.INEEL/CON-2000-00104 PREPRINT Spray-Formed Tooling for Injection Molding and Die Casting Applications K. M. McHugh B. R. Wickham June 26, 2000 June 28, 2000 International Conference on Spray Deposition and Melt Atomization This is a preprint of a paper intended for publication in a journal or proceedings. Since changes may be made before publication, this preprint should not be cited or reproduced without permission of the author. This document was prepared as a account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, or any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for any third partys use, or the results of such use, of any information, apparatus, product or process disclosed in this report, or represents that its use by such third party would not infringe privately owned rights. The views expressed in this paper are not necessarily those of the U.S. Government or the sponsoring agency. BECHTEL BWXT IDAHO, LLC 1 Spray-Formed Tooling For Injection Molding and Die Casting Applications Kevin M. McHugh and Bruce R. Wickham Idaho National Engineering and Environmental Laboratory P.O. Box 1625 Idaho Falls, ID 83415-2050 e-mail: kmm4inel.gov Abstract Rapid Solidification Process (RSP) Tooling is a spray forming technology tailored for producing molds and dies. The approach combines rapid solidification processing and net-shape materials processing in a single step. The ability of the sprayed deposit to capture features of the tool pattern eliminates costly machining operations in conventional mold making and reduces turnaround time. Moreover, rapid solidification suppresses carbide precipitation and growth, allowing many ferritic tool steels to be artificially aged, an alternative to conventional heat treatment that offers unique benefits. Material properties and microstructure transformation during heat treatment of spray-formed H13 tool steel are described. Introduction Molds, dies, and related tooling are used to shape many of the plastic and metal components we use every day at home or at work. The process involves machining the negative of a desired part shape (core and cavity) from a forged tool steel or a rough metal casting, adding cooling channels, vents, and other mechanical features, followed by grinding. Many molds and dies undergo heat treatment (austenitization/quench/temper) to improve the properties of the steel, followed by final grinding and polishing to achieve the desired finish 1. Conventional fabrication of molds and dies is very expensive and time consuming because: Each is custom made, reflecting the shape and texture of the desired part. The materials used to make tooling are difficult to machine and work with. Tool steels are the workhorse of industry for long production runs. Machining tool steels is capital equipment intensive because specialized equipment is often needed for individual machining steps. Tooling must be machined accurately. Oftentimes many individual components must fit together correctly for the final product to function properly. 2 Costs for plastic injection molds vary with size and complexity, ranging from about $10,000 to over $300,000 (U.S.), and have lead times of 3 to 6 months. Tool checking and part qualification may require an additional 3 months. Large die-casting dies for transmissions and sheet metal stamping dies for making automobile body panels may cost more than $1million (U.S.). Lead times are usually greater than 40 weeks. A large automobile company invests about $1 billion (U.S.) in new tooling each year to manufacture the components that go into their new line of cars and trucks. Spray forming offers great potential for reducing the cost and lead time for tooling by eliminating many of the machining, grinding, and polishing unit operations. In addition, spray forming provides a powerful means to control segregation of alloying elements during solidification and carbide formation, and the ability to create beneficial metastable phases in many popular ferritic tool steels. As a result, relatively low temperature precipitation hardening heat treatment can be used to tailor properties such as hardness, toughness, thermal fatigue resistance, and strength. This paper describes the application of spray forming technology for producing H13 tooling for injection molding and die casting applications, and the benefits of low temperature heat treatment. RSP Tooling Rapid Solidification Process (RSP) Tooling, is a spray forming technology tailored for producing molds and dies 2-4. The approach combines rapid solidification processing and net- shape materials processing in a single step. The general concept involves converting a mold design described by a CAD file to a tooling master using a suitable rapid prototyping (RP) technology such as stereolithography. A pattern transfer is made to a castable ceramic, typically alumina or fused silica (Figure 1). This is followed by spray forming a thick deposit of tool steel (or other alloy) on the pattern to capture the desired shape, surface texture and detail. The resultant metal block is cooled to room temperature and separated from the pattern. Typically, the deposits exterior walls are machined square, allowing it to be used as an insert in a holding block such as a MUD frame 5. The overall turnaround time for tooling is about three days, stating with a master. Molds and dies produced in this way have been used for prototype and production runs in plastic injection molding and die casting. Figure 1. RSP Tooling processing steps. 3 An important benefit of RSP Tooling is that it allows molds and dies to be made early in the design cycle for a component. True prototype parts can be manufactured to assess form, fit, and function using the same process planned for production. If the part is qualified, the tooling can be run in production as conventional tooling would. Use of a digital database and RP technology allows design modifications to be easily made. Experimental Procedure An alumina-base ceramic (Cotronics 780 6) was slurry cast using a silicone rubber master die, or freeze cast using a stereolithography master. After setting up, ceramic patterns were demolded, fired in a kiln, and cooled to room temperature. H13 tool steel was induction melted under a nitrogen atmosphere, superheated about 100C, and pressure-fed into a bench-scale converging/diverging spray nozzle, designed and constructed in-house. An inert gas atmosphere within the spray apparatus minimized in-flight oxidation of the atomized droplets as they deposited onto the tool pattern at a rate of about 200 kg/h. Gas-to-metal mass flow ratio was approximately 0.5. For tensile property and hardness evaluation, the spray-formed material was sectioned using a wire EDM and surface ground to remove a 0.05 mm thick heat-affected zone. Samples were heat treated in a furnace that was purged with nitrogen. Each sample was coated with BN and placed in a sealed metal foil packet as a precautionary measure to prevent decarburization. Artificially aged samples were soaked for 1 hour at temperatures ranging from 400 to 700C, and air cooled. Conventionally heat treated H13 was austenitized at 1010C for 30 min., air quenched, and double tempered (2 hr plus 2 hr) at 538C. Microhardness was measured at room temperature using a Shimadzu Type M Vickers Hardness Tester by averaging ten microindentation readings. Microstructure of the etched (3% nital) tool steel was evaluated optically using an Olympus Model PME-3 metallograph and an Amray Model 1830 scanning electron microscope. Phase composition was analyzed via energy- dispersive spectroscopy (EDS). The size distribution of overspray powder was analyzed using a Microtrac Full Range Particle Analyzer after powder samples were sieved at 200 m to remove coarse flakes. Sample density was evaluated by water displacement using Archimedes principle and a Mettler balance (Model AE100). A quasi 1-D computer code developed at INEEL was used to evaluate multiphase flow behavior inside the nozzle and free jet regions. The codes basic numerical technique solves the steady- state gas flow field through an adaptive grid, conservative variables approach and treats the droplet phase in a Lagrangian manner with full aerodynamic and energetic coupling between the droplets and transport gas. The liquid metal injection system is coupled to the throat gas dynamics, and effects of heat transfer and wall friction are included. The code also includes a nonequilibrium solidification model that permits droplet undercooling and recalescence. The code was used to map out the temperature and velocity profile of the gas and atomized droplets within the nozzle and free jet regions. 4 Results and Discussion Spray forming is a robust rapid tooling technology that allows tool steel molds and dies to be produced in a straightforward manner. Examples of die inserts are given in Figure 2. Each was spray formed using a ceramic pattern generated from a RP master. Figure 2. Spray-formed mold inserts. (a) Ceramic pattern and H13 tool steel insert. (b) P20 tool steel insert. Particle and Gas Behavior Particle mass frequency and cumulative mass distribution plots for H13 tool steel sprays are given in Figure 3. The mass median diameter was determined to be 56 m by interpolation of size corresponding to 50% cumulative mass. The area mean diameter and volume mean diameter were calculated to be 53 m and 139 m, respectively. Geometric standard deviation, d =(d 84 /d 16 ) , is 1.8, where d 84 and d 16 are particle diameters corresponding to 84% and 16% cumulative mass in Figure 3. 5 Figure 3. Cumulative mass and mass frequency plots of particles in H13 tool step sprays. Figure 4 gives computational results for the multiphase velocity flow field (Figure 4a), and H13 tool steel solid fraction (Figure 4b), inside the nozzle and free jet regions. Gas velocity increases until reaching the location of the shock front, at which point it precipitously decreases, eventually decaying exponentially outside the nozzle. Small droplets are easily perturbed by the velocity field, accelerating inside the nozzle and decelerating outside. After reaching their terminal velocity, larger droplets (150 m) are less perturbed by the flow field due to their greater momentum. It is well known that high particle cooling rates in the spray jet (10 3 -10 6 K/s) and bulk deposit (1- 100 K/min) are present during spray forming 7. Most of the particles in the spray have undergone recalescence, resulting in a solid fraction of about 0.75. Calculated solid fraction profiles of small (30 m) and large (150 m) droplets with distance from the nozzle inlet, are shown in Figure 4b. Spray-Formed Deposits This high heat extraction rate reduces erosion effects at the surface of the tool pattern. This allows relatively soft, castable ceramic pattern materials to be used that would not be satisfactory candidates for conventional metal casting processes. With suitable processing conditions, fine 6 Figure 4. Calculated particle and gas behavior in nozzle and free jet regions. (a) Velocity profile. (b) Solid fraction. 7 surface detail can be successfully transferred from the pattern to spray-formed mold. Surface roughness at the molding surface is pattern dependent. Slurry-cast commercial ceramics yield a surface roughness of about 1 m Ra, suitable for many molding applications. Deposition of tool steel onto glass plates has yielded a specular surface finish of about 0.076 m Ra. At the current state of development, dimensional repeatability of spray-formed molds, starting with a common master, is about 0.2%. Chemistry The chemistry of H13 tool steel is designed to allow the material to withstand the temperature, pressure, abrasion, and thermal cycling associated with demanding applications such as die casting. It is the most popular die casting alloy worldwide and second most popular tool steel for plastic injection molding. The steel has low carbon content (0.4 wt.%) to promote toughness, medium chromium content (5 wt%) to provide good resistance to high temperature softening, 1 wt% Si to improve high temperature oxidation resistance, and small molybdenum and vanadium additions (about 1%) that form stable carbides to increase resistance to erosive wear 8. Composition analysis was performed on H13 tool steel before and after spray forming. Results, summarized in Table 1, indicate no significant variation in alloy additions. Table 1. Composition of H13 tool steel Element C Mn Cr Mo V Si Fe Stock H13 0.41 0.39 5.15 1.41 0.9 1.06 Bal. Spray Formed H13 0.41 0.38 5.10 1.42 0.9 1.08 Bal. Microstructure The size, shape, type, and distribution of carbides found in H13 tool steel is dictated by the processing method and heat treatment. Normally the commercial steel is machined in the mill annealed condition and heat treated (austenitized/quenched/tempered) prior to use. It is typically austenitized at about 1010C, quenched in air or oil, and carefully tempered two or three times at 540 to 650C to obtain the required combination of hardness, thermal fatigue resistance, and toughness. Commercial, forged, ferritic tool steels cannot be precipitation hardened because after electroslag remelting at the steel mill, ingots are cast that cool slowly and form coarse carbides. In contrast, rapid solidification of H13 tool steel causes alloying additions to remain largely in solution and to be more uniformly distributed in the matrix 9-11. Properties can be tailored by artificial aging or conventional heat treatment. A benefit of artificial aging is that it bypasses the specific volume changes that occur during conventional heat treatment that can lead to tool distortion. These specific volume changes occur as the matrix phase transforms from ferrite to austenite to tempered martensite and must be accounted for in the original mold design. However, they cannot always be reliably predicted. Thin sections in the insert, which may be desirable from a design and production standpoint, are oftentimes not included as the material has a tendency to slump during austenitization or distort 8 during quenching. Tool distortion is not observed during artificial aging of spray-formed tool steels because there is no phase transformation. An optical photomicrograph of spray-formed H13 is shown in Figure 5 together with an SEM image, in backscattered electron (BSE) mode. Energy dispersive spectroscopic (EDS) composition analysis of some features in the photomicrographs is also given. While exact quantitative data is not possible due to sampling volume limitations, results suggest that grain boundaries are particularly rich in V. Intragranular (matrix) regions are homogeneous and rich in Fe. X-ray diffraction analysis indicates that the matrix phase is primarily ferrite (bainite) with very little retained austenite, and that the alloying elements are largely in solution. Discrete intragranular carbides are relatively rare, very small (about 0.1 m) and predominately vanadium-rich MC carbides. M 2 C carbides are not observed. Element Si V Cr Mn Mo Fe Spot #1 (wt%) 0.61 32.13 6.68 0.17 2.05 58.36 Spot #2 (wt%) 1.59 0.79 5.35 0.28 2.28 89.72 Figure 5. Photomicrographs of as-deposited H13 tool steel. 3% nital etch. (a) Optical photomicrograph. (b) SEM image (BSE mode) near a grain boundary. Table gives EDS composition of numbered features. 9 Figure 6 illustrates the microstructure of spray-formed H13 aged at 500C for 1 hr. During aging, grain boundaries remain well defined, perhaps coarsening slightly compared to as- deposited H13 (Figure 5). The most prominent change is the appearance of very fine (0.1 m diameter) vanadium-rich MC carbide precipitates. The precipitates are uniformly distributed throughout the matrix and increase the hardness and wear resistance of the tool steel. Increasing the soak temperature to 700C results in prominent carbide coarsening, the formation of M 7 C 3 and M 6 C carbides, and a decrease in hardness. The photomicrographs of Figure 7 illustrate the dramatic change in carbide size. BSE imaging clearly differentiates Mo/Cr-rich carbides from V-rich carbides, shown as light and dark areas, respectively, in Figure 7. EDS analysis of these carbides is also given in Figure 7. Element Si V Cr Mn Mo Fe Spot #1 (wt%) 0.06 13.80 7.20 2.64 2.44 73.86 Spot #2 (wt%) 1.52 0.82 5.48 0.23 2.38 89.57 Figure 6. Photomicrographs of spray-formed/aged H13 tool steel. 500C soak for 1 hr. 3% nital etch. (a) Optical photomicrograph. (b) SEM image (BSE mode) near a grain boundary. Table gives EDS composition of numbered features. 10 Element Si V Cr Mn Mo Fe Spot #1 (wt%) 0 82.27 9.01 0 4.33 4.39 Spot #2 (wt%) 0 5.30 25.70 0 55.55 13.45 Spot #3 (wt%) 1.60 0.88 6.32 0.28 2.92 88.00 Figure 7. SEM Photomicrograph (BSE mode) of spray-formed/aged H13 tool steel showing adjacent V-rich (dark) and Mo/Cr-rich (light) carbides. 700C soak for 1/2 hr, 3% nital etch. Table gives EDS composition of numbered features. Material Properties Porosity in spray-formed metals depends on processing conditions. The average as-deposited density of spray-formed H13 was 98-99% of theoretical, as measured by water displacement using Archimedes principle. As-deposited hardness was typically about 59 HRC, harder than commercial forged and heat treated material (28 to 53 HRC depending on tempering temperature), and significantly harder than annealed H13 (200 HB). The high hardness is attributable to lattice strain due to quenching stresses and supersaturation. As shown in Figure 8, hardness can be varied over a wide range by artificial aging. 59 HRC as- deposited samples were given isochronal (1 hr) soaks at 50C increments from 400 to 700C, air cooled, and evaluated for microhardness. At 400C, a small decrease in hardness was observed, presumably due to stress relieving. As the soak temperature was further increased, hardness rose to a peak hardness of approximately 62 HRC at 500C. Higher soak temperature resulted in a drop in hardness as carbide particles coarsened. Peak age hardness in spray-formed H13 tool steel is notably higher than that of commercial hardened material. Normally, commercial H13 dies used in die casting are tempered to about 40 to 45 HRC as a tradeoff since high hardness dies, while desirable for wear resistance, are prone to premature failure via thermal fatigue as the dies surface is rapidly cycled from 300C to 700C during aluminum production runs. 11 Figure 8. Hardness of artificially aged spray-formed H13 tool steel following one hour soaks at temperature. Hardness range of conventionally heat treated H13 included for comparison. As-deposited spray-formed material was also hardened following the conventional heat treatment cycle used with commercial material. Samples of forged/mill annealed commercial and spray- formed materials were austenitized at 1010C, air quenched, and double tempered (2 hr plus 2 hr) at (538C). The microstructure in both cases was found to be tempered martensite with a few spheroidal particles of alloy carbide. Hardness values for both materials were very nearly identical. Table 2 gives the ultimate tensile strength and yield strength of spray-formed, cast, and forged/heat treated H13 tool steel measured at test temperatures of 22 and 550C. Values for spray formed H13 are given in the as-deposited condition and following artificial aging and conventional heat treatments. Values for the spray-formed material are comparable to those of forged and are considerably higher than those of cast tool steel. The spray-formed material seems to retain its strength somewhat better than forged/heat treated H13 at higher temperatures. 12 Table 2. H13 tool steel mechanical properties. Sample/Heat Treatment Ultimate Tensile Strength (MPa) Yield Strength (MPa) Test Temperature (C) Spray formed/as-deposited 1061 951