Y210—2型電動(dòng)機(jī)定子鐵芯沖壓模具設(shè)計(jì)

Y2102型電動(dòng)機(jī)定子鐵芯沖壓模具設(shè)計(jì),Y2102型電動(dòng)機(jī)定子鐵芯沖壓模具設(shè)計(jì),y210,電動(dòng)機(jī),定子,沖壓,模具設(shè)計(jì) Y2102型電動(dòng)機(jī)定子鐵芯沖壓模具設(shè)計(jì)一、 產(chǎn)品零件的工藝分析零件簡圖該電動(dòng)機(jī)定子鐵芯的材料為電工硅鋼片D21，鋼板厚度0.50mm，具有良好的沖裁性能。零件形狀簡單，對稱，是由圓弧和直線組成。對于沖小孔5，沖復(fù)雜圓孔80，按照沖壓手冊一般沖孔模對該材料（鋼400MPa）可以沖壓的最小的孔徑為dt=0.5mm，因而小孔符合工藝要求。最小孔邊距為b=3.5mmt，因而符合孔邊距工藝要求，以上分析均符合沖裁工藝要求。由表 1、2 查出沖裁件內(nèi)外所能達(dá)到的經(jīng)濟(jì)精度為IT11，孔中心與邊緣距離尺寸公差為0.6，對于孔心距公差為0.1，將以上精度與零件簡圖中所標(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，其他尺寸標(biāo)準(zhǔn)、生產(chǎn)批量等情況，也均符合沖裁的工藝要求，故決定采用沖孔落料復(fù)合沖裁模進(jìn)行加工，且一次成形。表1 沖裁件內(nèi)外形所能達(dá)到的經(jīng)濟(jì)精度 基本尺寸/mm材料厚度t/mm3366101018185001IT12IT13IT1112IT14IT12IT13IT11表2 孔中心與邊緣距離尺寸公差材料厚度t孔中心與邊緣距離尺寸505012012022022036020.50.60.70.8240.60.70.81.0二、模具類型的確定常見的模具形式可分為單工序模、復(fù)合模和級進(jìn)模三種。確定模具形式，應(yīng)以沖裁工件的要求、生產(chǎn)批量、模具加工條件為主要依據(jù)。沖壓生產(chǎn)批量與合理模具形式見表3 ，單工序模、級進(jìn)模和復(fù)合模的比較見表4 表3 沖壓生產(chǎn)批量與合理模具形式批量/（千件/每年）項(xiàng)目單件小批中批大批大量大件中件小件1130010005000模具形式簡易模單工序模單工序模簡易模級進(jìn)模、復(fù)合模單工序模級進(jìn)模、復(fù)合模級進(jìn)模、復(fù)合模設(shè)備形式通用壓機(jī)通用壓機(jī)高速壓機(jī)自動(dòng)和半自動(dòng)通用壓機(jī)機(jī)械化高速壓機(jī)自動(dòng)機(jī)專用壓機(jī)與自動(dòng)機(jī)表 4 單工序模、級進(jìn)模和復(fù)合模的比較比較項(xiàng)目單工序模級進(jìn)模復(fù)合模工件尺寸精度較低一般,IT11級以下較高,IT9級以下工件形位公差工件不平整,同軸度、對稱度及位置度誤差大不太平整，有時(shí)要較平，同軸度、位置度誤差較大工件平整，同軸度、對稱度及位置誤差大沖壓生產(chǎn)率低，沖床一次行程內(nèi)只能完成一個(gè)工序高，沖床在一次行程內(nèi)能完成多個(gè)工序較高，沖床在一次行程內(nèi)可完成兩個(gè)以上工序?qū)崿F(xiàn)操作機(jī)械化、自動(dòng)化的可能性較易，尤其適合多工位沖床上實(shí)現(xiàn)自動(dòng)化容易，尤其適應(yīng)于單機(jī)上實(shí)現(xiàn)自動(dòng)化難，工件與廢料排除較復(fù)雜，只能在單機(jī)上實(shí)現(xiàn)部分機(jī)械化操作對材料的要求對條料寬度要求不嚴(yán)，可用邊角料對條料或帶料寬度要求嚴(yán)格對條料寬度要求不嚴(yán)，可用邊角料生產(chǎn)安全行安全性較差比較安全安全性較差模具制造的難易程度較易，結(jié)構(gòu)簡單，制造周期短，價(jià)格低形狀簡單件，比用復(fù)合模制造難度低形狀復(fù)雜件，比用級進(jìn)模的制造難度低應(yīng)用通用性好，適合中、小批量生產(chǎn)和大型件的大量生產(chǎn)通用性較差，適合于形狀簡單，尺寸不大，精度要求不高件的大批量生產(chǎn)通用性較差，適于形狀復(fù)雜、尺寸不大、精度要求較高件的大批量生產(chǎn)通過以上關(guān)系比較，此工件是大批量生產(chǎn)，故采用沖孔落料復(fù)合沖裁模進(jìn)行加工，且一次沖壓成行。所謂復(fù)合模具結(jié)構(gòu)，就是在沖床的一次行程內(nèi)，完成兩道以上的沖壓工序。在完成這些工序過程中，沖件材料無需進(jìn)給移動(dòng)。復(fù)合模具結(jié)構(gòu)的優(yōu)點(diǎn)（1）制件精度高。由于是在沖床的一次行程內(nèi)，完成數(shù)道沖壓工序。因而不存在累積定位誤差。使沖出的制件內(nèi)外形相對位置及各件的尺寸一致性非常好，制件平直。適宜沖制薄料和脆性或軟質(zhì)材料。（2）生產(chǎn)效率高。（3）模具結(jié)構(gòu)緊湊，面積較小。復(fù)合模具結(jié)構(gòu)的選用原則：只有當(dāng)制件精度要求高，生產(chǎn)批量大，表面要求平整時(shí)，才選用復(fù)合模具結(jié)構(gòu)。三、沖裁間隙的選用 在沖裁模的設(shè)計(jì)中,凸凹模間隙的合理選取,是保證模具正常工作、提高沖片質(zhì)量、延長模具壽命的一個(gè)關(guān)鍵因素。理想的間隙應(yīng)該是板料沖裁斷裂時(shí),凸凹模刃口邊所產(chǎn)生的裂紋在一條直線上,否則沖片邊緣將出現(xiàn)不允許的毛刺,使得刃口粘結(jié)嚴(yán)重,磨損加快,進(jìn)而影響模具的壽命。所以,如何選取合理的凸凹模間隙,是模具設(shè)計(jì)時(shí)不容忽視的問題。為0. 5mm 的硅鋼片, 手冊表5推薦的間隙為0 . 0 6 0. 08mm（見表 ） ,約為材料厚度的8 %14 %。按照這個(gè)間隙,沖出的定、轉(zhuǎn)子片毛刺雖能控制在規(guī)定范圍內(nèi)。但由于間隙偏小,使得凸模與被沖的孔之間、凹模與落料之間的摩擦嚴(yán)重,造成凸模和凹模側(cè)壁產(chǎn)生粘結(jié),卸料力增大,影響沖片斷面的質(zhì)量,刃口容易變鈍,沖片易出毛刺,且毛刺增長過快,甚至發(fā)生凹模脹裂現(xiàn)象,致使模具壽命下降。且取小間隙時(shí),由于彈性回跳作用,落料件尺寸大于凹模,沖出的孔徑小于凸模,從而造成沖片的尺寸精度出現(xiàn)誤差。表5 落料、沖孔模刃口始用間隙 厚度t硅鋼片0.10.20.30.50.81.0Zmin0.010.0150.030.060.100.13Zmax0.030.0350.050.080.130.16為提高沖片質(zhì)量,延長模具壽命,根據(jù)國內(nèi)外資料信息,在實(shí)踐中對模具間隙做了試驗(yàn)摸索,證明放大間隙是非常有效的。經(jīng)過多次對0. 5mm 厚硅鋼片沖裁的試驗(yàn),發(fā)現(xiàn)間隙值在材料厚度的20 %左右范圍內(nèi),即間隙值為0. 090. 11mm 最為合適。采用這個(gè)間隙,可以獲得如下效果:(1) 提高了沖片質(zhì)量。刃口鋒利時(shí)毛刺小,沖裁過程中毛刺增長緩慢。(2) 沖片表面平整度大大改善,特別是相鄰孔之間。(3) 凸凹模側(cè)壁無粘結(jié),減小了卸料力。(4) 延長了模具壽命。刃磨一次可以保證較的沖次,從而減少刃磨次數(shù),提高了生產(chǎn)效率。實(shí)踐證明,合理地放大間隙,可使沖裁質(zhì)量得到有效的保證,且模具壽命能提高23 倍。四、排樣 見下圖 為直排有廢料排樣方式 由表 6 查得最小搭邊值a=1.5 a=1.5表6 沖裁金屬材料的搭邊值料厚手送料圓形非圓形aaaa11.51.521.5 排樣圖毛胚面積 A=條料寬度 b=150+1.52=153進(jìn)距 h=150+1.5=151.5材料利用率 五、計(jì)算沖壓力：采用彈性卸料和上出料方式 硅鋼片D21的=190MPa落料力 F=Lt=（4710.5230）N=54.165N沖孔力 F= Lt=（4410.5230+15.790.5230）N=66.965N卸料力 F=KF=0.0554.165=27.0825N查表7 取K=0.05推件力 F=nKF=100.06566.965=32.964N查表7 取K=0.065表7 卸料力、推件力和頂出力因數(shù)料厚/mmKKK鋼0.10.060.090.10.140.10.50.040.070.0650.08選擇沖床時(shí)的總沖壓力為 F= F+ F +F+ F=140.553N六、確定模具壓力中心因?yàn)樵摿慵侵行膶ΨQ圖形，所以其壓力中心位于輪廓圖形的幾何中心O點(diǎn)，如圖所示壓力中心七、計(jì)算凸、凹模的刃口尺寸根據(jù)沖裁間隙分析 Zmin=0.09mm Zmax=0.11mm，對零件圖中未注公差的尺寸，由公差手冊查出其極限偏差為、對于外輪廓150，查表 8 的凸、凹模的制造公差=0.030 =0.040表8 規(guī)則形狀（圓形、方形件）沖裁時(shí)凸模，凹模的制造公差基本尺寸凸模公差凹模公差180.0200.0201502000.0300.040由于ZmaxZmin=0.02mm +不滿足條件，不可采用分開加工凸模和凹模，故采用凸模和凹模配合加工方法，以凹模為基準(zhǔn)件。查表 9 的因數(shù)X=0.75表9 因數(shù)X材料厚度t/mm非圓形x值圓形x值10.750.50.750.5工件公差/mm10.160.170.350.360.160.16落料凹模刃口尺寸計(jì)算如下：150 ： Bj=（Bmin+x）150=（150+0.750.1）=150.075 mm沖孔凸模刃口尺寸計(jì)算如下：5 ：d=（d+x）=（5+0.50.24）=5.12 mmd按凸模尺寸配制其雙面間隙為0.090.11mm對于沖孔80，零件形狀比較復(fù)雜，且為薄材料為了保證凸、凹模之間的間隙值，必須采用凸模和凹模配合加工方法，以凸模為基準(zhǔn)件根據(jù)凸模磨損后的尺寸變化情況將零件圖中各尺寸進(jìn)行分類A類：、R4B類： 、C類： 、沖孔凸模刃口尺寸計(jì)算如下：Aj=（Amaxx）5=（5-0.750.1）=4.925mm4=（4-0.50.2）=3.9mmBj=（Bmin+x）110=（110+0.50.87）=110.435mmCj=（Cmin+x）2=（2+0.750.1）=2.0750.0125mm5=（5+0.50.2）=5.10.025mm=（+0.5）= mm凸模的刃口尺寸按凹模實(shí)際尺寸配制并保證雙面間隙0.090.11mm八、沖裁的部件及零件設(shè)計(jì)模具的零部件，有很大一部分已實(shí)現(xiàn)了標(biāo)準(zhǔn)化，這對于簡化設(shè)計(jì)工作、穩(wěn)定模具質(zhì)量、簡化模具的制造維修等，都具有重大意義。在設(shè)計(jì)模具時(shí)，對于標(biāo)準(zhǔn)化的零部件，只需在標(biāo)準(zhǔn)化的資料中正確的選擇，大量的設(shè)計(jì)工作是對非標(biāo)準(zhǔn)件的設(shè)計(jì)。 根據(jù)在模具中的功能和特點(diǎn)，可以分成兩類：工藝零件：這類零件直接參與完成工藝過程并和毛坯直接發(fā)生作用。結(jié)構(gòu)零件：這類零件不直接參與完成工藝過程，也不和毛坯直接發(fā)生作用。沖模零件的詳細(xì)分類見表10表10 沖模零件分類工藝零件結(jié)構(gòu)零件工作零件定位零件卸料和壓料零件導(dǎo)向零件支撐零件緊固零件其他零件凸模凹模凸凹模擋料銷始用擋料銷導(dǎo)正銷定位銷、定位板導(dǎo)料銷、導(dǎo)料板側(cè)刃、側(cè)刃擋塊承料板卸料裝置壓料裝置頂件裝置推件裝置廢料裝置導(dǎo)柱導(dǎo)套導(dǎo)板導(dǎo)筒上、下模座模柄凸、凹模固定板墊板限位支撐裝置螺釘銷釘鍵彈性件傳動(dòng)零件1、工作零件凸模凸模形式 沖孔：圓形凸模，設(shè)計(jì)成直柱形式 圖樣見下圖落料：異形凸模 圖樣見下圖注：按0.090.11mm間隙與落料凹模配制凹模凹模的刃口形式，考慮到生產(chǎn)批量較大，所采用刃口強(qiáng)度較高，即柱形刃口筒形凹模的外形尺寸 厚度H=Kb=0.15150=22.5mm 查表11 k=0.15表11 因數(shù)K的數(shù)值b/mm料厚t/mm0.511002000.150.18壁厚 C=1.5H=33.75mm 當(dāng)t=0.5mm時(shí) 取h=3mm 尺寸：217.5217.522.5 標(biāo)注如下圖落料凹模按以上計(jì)算的凹模外形尺寸，可以保證凹模有足夠的強(qiáng)度和剛度，一般可不用進(jìn)行強(qiáng)度校核。凸凹模復(fù)合模的結(jié)構(gòu)特點(diǎn)是一定有一個(gè)凸凹模。凸凹模的內(nèi)、外緣均為刃口，為保證強(qiáng)度，內(nèi)外緣之間壁厚應(yīng)有一定厚度，取決于沖裁件尺寸。該凸凹模的最小壁厚為3.5mm。通過表12 校核，可知凸凹模壁厚有足夠的強(qiáng)度。根據(jù)彈性卸料板厚度及模具結(jié)構(gòu)可選取凸凹模的高度為80mm。表12復(fù)合模最小壁厚沖裁材料材料厚度0.50.60.81硅鋼，中碳鋼1.21.51.52.0（2.02.5）t其結(jié)構(gòu)如下圖沖孔凹模、落料凹模、凸凹模的材料選用：根據(jù)沖裁零件電工硅鋼片加工強(qiáng)度，變形抗力大，模具承受載荷增加，刃口部位磨損加快，且生產(chǎn)批量為105 件，則考慮選用合金含量高，耐磨性好的Cr12MoV材料。Cr12MoV鋼有高淬透性，可用來制造斷面較大，形狀復(fù)雜，經(jīng)受較大沖擊負(fù)載的各種模具，熱處理硬度為HRC6163。2、定位零件為了保證模具正常工作和沖出合格沖裁件，必須保證坯料或工序件對模具的工作刃口處于正確的相對位置，即必須定位。條料在模具送料平面中必須有兩個(gè)方向的限位：一是在與送料方向垂直的方向上限位，保證條料沿正確的方向送進(jìn)，稱為條料橫向定位或送進(jìn)導(dǎo)向；二是在送料方向上的限位，控制條料一次送進(jìn)的距離（步距），稱為條料縱向定位或送料定距。對于塊料或工序件的定位，基本上也是在兩個(gè)方向上的限位。 毛坯的定位條料橫向定位裝置在復(fù)合沖裁模上，通常采用導(dǎo)料銷進(jìn)行導(dǎo)料。兩個(gè)導(dǎo)料銷的中心距盡可能取大一些，以便于送料。并有利于防止條料偏斜。條料縱向定位裝置在復(fù)合模中，縱向定位的主要作用是保證縱向搭邊值。擋料銷確保條料送進(jìn)時(shí)有準(zhǔn)確的送進(jìn)距。活動(dòng)擋料銷常用于倒裝復(fù)合模，裝在卸料板上，由彈性元件支撐，可以伸縮的擋料銷。設(shè)計(jì)中選取橡膠彈性擋料銷。國家標(biāo)準(zhǔn)結(jié)構(gòu)如下圖3、卸料、出件零件卸料裝置卸料是指把沖件或廢料從凸模中卸下來?？煞譃閯傂院蛷椥孕读涎b置兩種形式，視模具的結(jié)構(gòu)選擇。設(shè)計(jì)中為倒裝復(fù)合模，易采用彈性卸料裝置。彈性卸料裝置卸料力較小，所得質(zhì)量較好，平直度較高。彈性元件選用橡膠，其結(jié)構(gòu)如下圖推件裝置設(shè)計(jì)中模柄中心位置有沖孔凸模，采用簡單的剛性推件裝置，由打桿、推板、連接推桿和推件塊組成。結(jié)構(gòu)如下圖4、橡膠的選用橡膠允許承受的負(fù)荷比彈簧大，且安裝調(diào)整方便，價(jià)錢又不貴，是模具中廣泛使用的彈性元件。冷沖模中所用橡膠一般為聚氨脂橡膠（PUR）。橡膠的高度H與直徑D應(yīng)有適當(dāng)?shù)谋壤?，一般?yīng)保持H=（0.51.5）D5、模架及零件模架是由上模座、下模座、模柄及導(dǎo)向裝置組成對模架的基本要求：應(yīng)有足夠的強(qiáng)度與剛度應(yīng)有足夠的精度上下模之間的導(dǎo)向應(yīng)精確。一般模架型號規(guī)格均已列入標(biāo)準(zhǔn)，設(shè)計(jì)時(shí)可選用模架選用適用中等精度，中、小尺寸沖壓件的后側(cè)導(dǎo)柱模架從右向左送料，操作方便。上模座：L/mm B/mm H/mm=25025045下模座：L/mm B/mm H/mm=25025055導(dǎo)柱： d/mm L/mm=35180導(dǎo)套： d/mm L/mmD/mm=3511543模架的閉合高度：190230模柄中小型模具都是通過模柄固定在壓力機(jī)滑塊上。設(shè)計(jì)中采用凸緣式模柄形式見下圖模柄的長度不得大于沖床滑塊里模柄孔的深度，模柄直徑應(yīng)與模柄孔一致。連接零件的選取墊板厚度?。?0mm 材料：45 硬度：4348HRC凸模固定板厚度取：12mm 材料：45卸料板厚度?。?5mm 材料：Q235橡膠厚度取：40mm6、模具的閉合高度模具的閉合高度H模 是指模具在最低工作位置時(shí)，上、下模之間的距離。為使模具正常工作，模具閉合高度必須與沖床的閉合高度相適應(yīng)。應(yīng)介于沖床最大和最小閉合高度之間: H最大-5H模H最小+10 H模 =45+10+12+22.5+0.5+80+55-2=223九、沖壓設(shè)備的選擇為安全起見，防止設(shè)備的超載，參照沖壓手冊可選取公稱壓力為63KN的開式雙柱可傾壓力機(jī)J2316該壓力機(jī)與模具設(shè)計(jì)的有關(guān)參數(shù)為：公稱壓力： 160KN 滑塊行程： 55mm最大閉合高度： 220mm 最大裝模高度： 180mm連桿調(diào)節(jié)量： 45mm 工作臺(tái)尺寸： 200310墊板尺寸： 30140 模柄孔尺寸： 3050十、模具經(jīng)濟(jì)和技術(shù)上的分析模具的經(jīng)濟(jì)性涉及到成本的高低供應(yīng)是否充分，加工過程是否復(fù)雜、成品率的高低以及同一產(chǎn)品中使用金屬或鋼材型號的多少等。在我國當(dāng)前情況下，考慮以鐵代鋼和以鑄代鍛還是符合經(jīng)濟(jì)性要求的，故選擇一般彈鋼和鑄鐵能滿足要求的，就不要選用合金鋼。對一些只要求表面性能高的零件，可選用廉價(jià)鋼種，然后進(jìn)行表面強(qiáng)化處理來達(dá)到。另外，在考慮材料經(jīng)濟(jì)性時(shí)，切記不宜單純以單價(jià)來比較材料的好壞，而應(yīng)以綜合效益來評價(jià)材料的經(jīng)濟(jì)性高低。模具的技術(shù)分析，包括模具的結(jié)構(gòu)、形狀以及尺寸等方面的分析。模具的結(jié)構(gòu)、形狀和尺寸設(shè)計(jì)計(jì)算完畢之后，要對模具的加工質(zhì)量、使用條件提出基本要求，這些要求主要是：（1）有適中而均勻的硬度，模具經(jīng)淬火、回火處理后，其硬度值為HRC40-52（根據(jù)模具的尺寸而定，尺寸越大，要求的硬度越低）。 （2）有足夠高的制造精度，模具的形位公差和尺寸公差應(yīng)符合圖紙的要求（一般按負(fù)公差制造），配合尺寸具有良好的互換性。 （3）有足夠高的表面粗糙度，配合表面應(yīng)達(dá)Ra3.2-1.6m，工作帶表面達(dá)Ra1.6-0.4m，表面應(yīng)進(jìn)行氮化處理、磷化處理或其它表面強(qiáng)化處理，如多元素共滲處理及化學(xué)熱處理等。 （4）有良好的對中性、平行度、直線度和垂直度，配合面的接觸率應(yīng)大于80。 （5）模具無內(nèi)部缺陷和表面缺陷，一般應(yīng)進(jìn)行超聲波探傷和表面質(zhì)量檢查后才能使用。十一、參考書目沖模設(shè)計(jì)應(yīng)用實(shí)例模具實(shí)用技術(shù)叢書編委，機(jī)械工業(yè)出版社模具設(shè)計(jì)與制造黨根茂 駱志斌 李集仁編，西安電子科技大學(xué)出版社機(jī)械工程材料王渙庭 李茅花 徐善國編，大連理工大學(xué)出版社圖學(xué)基礎(chǔ)教程譚建榮張樹有等編，高等教育出版社機(jī)械制造基礎(chǔ)嚴(yán)霖元主編，江西農(nóng)業(yè)大學(xué)機(jī)械設(shè)計(jì)邱宣懷主編，高等教育出版社沖壓工藝學(xué)李碩本主編，機(jī)械工業(yè)出版社模具設(shè)計(jì)與制造簡明手冊馮炳堯等編，上海科學(xué)技術(shù)出版社實(shí)用模具技術(shù)手冊鄧石城 王旭編，上?？茖W(xué)技術(shù)出版社沖模設(shè)計(jì)手冊張鼎承主編，機(jī)械工業(yè)出版社冷沖模設(shè)計(jì)丁松聚主編，機(jī)械工業(yè)出版社模具結(jié)構(gòu)與設(shè)計(jì)基礎(chǔ)許發(fā)樾主編，機(jī)械工業(yè)出版社沖模技術(shù)涂光祺主編，機(jī)械工業(yè)出版社冷沖壓工藝及模具設(shè)計(jì)劉心治編，重慶大學(xué)出版社模具制造工藝與裝備孫風(fēng)勤編，機(jī)械工業(yè)出版社沖壓手冊王孝培主編，機(jī)械工業(yè)出版社沖模圖冊李天佑編，機(jī)械工業(yè)出版社現(xiàn)代沖壓技術(shù)張毅編，國防工業(yè)出版社18沖壓成形與板材沖壓 1 概述通過模具使板材產(chǎn)生塑性變形而獲得成品零件的一次成形工藝方法叫做沖壓。由于沖壓通常在冷態(tài)下進(jìn)行，因此也稱為冷沖壓。只有當(dāng)板材厚度超過8100mm時(shí)，才采用熱沖壓。沖壓加工的原材料一般為板材或帶材，故也稱板材沖壓。某些非金屬板材（如膠木板、云母片、石棉、皮革等）亦可采用沖壓成形工藝進(jìn)行加工。沖壓廣泛應(yīng)用于金屬制品各行業(yè)中，尤其在汽車、儀表、軍工、家用電器等工業(yè)中占有極其重要的地位。沖壓成形需研究工藝設(shè)備和模具三類基本問題。 板材沖壓具有下列特點(diǎn)： （1）高的材料利用率。（2）可加工薄壁、形狀復(fù)雜的零件。（3）沖壓件在形狀和尺寸方面的互換性好。（4）能獲得質(zhì)量輕而強(qiáng)度高、剛性好的零件。（5）生產(chǎn)率高，操作簡單，容易實(shí)現(xiàn)機(jī)械化和自動(dòng)化。沖壓模具制作成本高，因此適合大批量生產(chǎn)。對于小批量、多品種生產(chǎn)，常采用簡易沖模，同時(shí)引進(jìn)沖壓加工中心等新型設(shè)備，以滿足市場求新求變的需求。板材沖壓常用的金屬材料有低碳鋼、銅、鋁、鎂合金及高塑性的合金剛等。如前所述，材料形狀有板材和帶材。沖壓生產(chǎn)設(shè)備有剪床和沖床。剪床是用來將板材剪切成具有一定寬度的條料，以供后續(xù)沖壓工序使用，沖床可用于剪切及成形。 2 沖壓成形的特點(diǎn)生產(chǎn)時(shí)間中所采用的沖壓成形工藝方法有很多，具有多種形式餓名稱，但塑性變形本質(zhì)是相同的。沖壓成形具有如下幾個(gè)非常突出的特點(diǎn)。 （1）垂直于板面方向的單位面積上的壓力，其數(shù)值不大便足以在板面方向上使板材產(chǎn)生塑性變形。由于垂直于板面方向上的單位面積上壓力的素質(zhì)遠(yuǎn)小于板面方向上的內(nèi)應(yīng)力，所以大多數(shù)的沖壓變形都可以近似地當(dāng)作平面應(yīng)力狀態(tài)來處理，使其變形力學(xué)的分析和工藝參數(shù)的計(jì)算大呢感工作都得到很大的簡化。 （2）由于沖壓成形用的板材毛胚的相對厚度很小，在壓應(yīng)力作用下的抗失穩(wěn)能力也很差，所以在沒有抗失穩(wěn)裝置（如壓邊圈等）的條件下，很難在自由狀態(tài)下順利地完成沖壓成形過程。因此，以拉應(yīng)力作用為主的伸長類沖壓成形過程多于以壓應(yīng)力作用為主的壓縮類成形過程。 （3）沖壓成形時(shí)，板材毛胚內(nèi)應(yīng)力的數(shù)值等于或小于材料的屈服應(yīng)力。在這一點(diǎn)上，沖壓成形與體積成形的差別很大。因此，在沖壓成形時(shí)變形區(qū)應(yīng)力狀態(tài)中的靜水壓力成分對成形極限與變形抗力的影響，已失去其在體積成形時(shí)的重要程度，有些情況下，甚至可以完全不予考慮，即使有必要考慮時(shí)，其處理方法也不相同。 （4）在沖壓成形時(shí)，模具對板材毛胚作用力所形成的約束作用較輕，不像體積成形（如模鍛）是靠與制件形狀完全相同的型腔對毛胚進(jìn)行全面接觸而實(shí)現(xiàn)的強(qiáng)制成形。在沖壓成形中，大多數(shù)情況下，板材毛胚都有某種程度的自由度，常常是只有一個(gè)表面與模具接觸，甚至有時(shí)存在板材兩側(cè)表面都有于模具接觸的變形部分。在這種情況下，這部分毛胚的變形是靠模具對其相鄰部分施加的外力實(shí)現(xiàn)其控制作用的。例如，球面和錐面零件成形時(shí)的懸空部分和管胚端部的卷邊成形都屬這種情況。 由于沖壓成形具有上述一些在變形與力學(xué)方面的特點(diǎn)，致使沖壓技術(shù)也形成了一些與體積成形不同的特點(diǎn)。由于不需要在板材毛的表面施加很大的單位壓力即可使其成形，所以在沖壓技術(shù)中關(guān)于模具強(qiáng)度與剛度的研究并不十分重要，相反卻發(fā)展了學(xué)多簡易模具技術(shù)。由于相同原因，也促使靠氣體或液體壓力成形的工藝方法得以發(fā)展。因沖壓成形時(shí)的平面應(yīng)力狀態(tài)或更為單純的應(yīng)變狀態(tài)（與體積成形相比），當(dāng)前對沖壓成形匯中毛胚的變形與 力能參數(shù)方面的研究較為深入，有條件運(yùn)用合理的科學(xué)方法進(jìn)行沖壓加工。借助于電子計(jì)算機(jī)與先進(jìn)的測試手段，在對板材性能與沖壓變形參數(shù)進(jìn)行實(shí)時(shí)測量與分析基礎(chǔ)上，實(shí)現(xiàn)沖壓過程智能化控制的研究工作也在開展。人們在對沖壓成形過程有離開較為深入的了解后，已經(jīng)認(rèn)識到?jīng)_壓成型與原材料有十分密切的關(guān)系。所以，對板材沖壓性能即成形性與形狀穩(wěn)定性的研究，目前已成為沖壓技術(shù)的一個(gè)重要內(nèi)容。對板材沖壓性能的研究工作不僅是沖壓技術(shù)發(fā)展的需要，而且也促進(jìn)了鋼鐵工業(yè)生產(chǎn)技術(shù)的發(fā)展，為其提高板材的質(zhì)量提供了一個(gè)可靠的基礎(chǔ)與依據(jù)。 3沖壓變形的分類 沖壓變形工藝可完成多種工序，其基本工序可分為分離工序和變形工序兩大類。分離工序是使胚料的一部分與另一部分相互分離的工藝方法，主要有落料、沖孔、切邊、剖切、修整等。其中又以沖孔、落料應(yīng)用最廣。變形工序是使胚料的一部分相對于另一部分產(chǎn)生位移而不破裂的工藝方法，主要有拉深、彎曲、局部成形、脹形、翻邊、縮徑、校形、旋壓等。從本質(zhì)上看，沖壓成形就是毛胚的變形區(qū)在外力的作用下產(chǎn)生相應(yīng)的塑性變形，所以變形區(qū)內(nèi)的應(yīng)力狀態(tài)和變形特點(diǎn)景象的沖壓成形分類，可以把成形性質(zhì)相同的成形方法概括成同一個(gè)類型并進(jìn)行體系化的研究。絕大多數(shù)沖壓成形時(shí)毛胚變形區(qū)均處于平面應(yīng)力狀態(tài)。通常認(rèn)為在板材表面上不受外力的作用，即使有外力作用，其數(shù)值也是較小的，所以可以認(rèn)為垂直于板面方向上的應(yīng)力為零，使板材毛胚產(chǎn)生塑性變形的是作用于板面方向上相互的兩個(gè)主應(yīng)力。由于板厚較小，通常都近似地認(rèn)為這兩個(gè)主應(yīng)力在厚度方向上是均勻分布的?；谶@樣的分析，可以把各種形式?jīng)_壓成型中的毛陪變形區(qū)的受力狀態(tài)與變形特點(diǎn)，在平面應(yīng)力的應(yīng)力坐標(biāo)系中與相應(yīng)的兩向應(yīng)變坐標(biāo)系中以應(yīng)力與應(yīng)變坐標(biāo)決定的位置來表示。4.沖壓用原材料 沖壓加工用原材料有很多種，它們的性能也有很大的差別，所以必須根據(jù)原材料的性能與特點(diǎn)，采用不同的沖壓成形方法、工藝參數(shù)和模具結(jié)構(gòu)，才能達(dá)到?jīng)_壓加工的目的。由于人們對沖壓成形過程板材毛胚的變形行為有了較為深入的認(rèn)識，已經(jīng)相當(dāng)清楚的建立了由原材料的化學(xué)成分、組織等因素所決定的材料性能與沖壓成形之間的關(guān)系，這就使原材料生產(chǎn)部門不但按照沖壓件的工作條件與使用要求進(jìn)行原材料的設(shè)計(jì)工作，而且也根據(jù)沖壓件加工過程對板材性能的要求進(jìn)行新型材料的開發(fā)工作，這是沖壓技術(shù)在原材料研究方面的一個(gè)重要方向。對沖壓用原材料沖壓性能方面的研究工作有（1）原材料沖壓性能的含義。（2）判斷原材料沖壓性能的科學(xué)方法，確定可以確切反映材料沖壓性能的參數(shù)，建立沖壓性能的參數(shù)與實(shí)際沖壓成形間的關(guān)系，以及沖壓性能參數(shù)的測試方法等。 （3）建立原材料的化學(xué)成分、組織和制造過程與沖壓性能之間的關(guān)系。沖壓用原材料主要是各種金屬與非金屬板材。金屬板材包括各種黑色技術(shù)和有色金屬板材。雖然在沖壓生產(chǎn)中所用金屬板材的種類很多，但最多的原材料蛀牙是鋼板、不銹鋼板、鋁合金板及各種復(fù)合金屬板。5板材沖壓性能及其鑒定方法 板材是指對沖壓加工的適應(yīng)能力。對板材沖壓性能的研究具有飛行重要的意義。為了能夠運(yùn)用最科學(xué)與最經(jīng)濟(jì)合理的沖壓工藝過程與工藝參數(shù)制造出沖壓零件，必須對作為加工對象的板材的性能具有十分清楚的了解，這樣才有可能充分地利用板材在加工方面的潛在能力。另一方面，為了能夠依據(jù)沖壓件的形狀與尺寸特點(diǎn)及其所需的成形工藝等基本因素，正確、合理地選用板材，也必須對板材的沖壓性能有一個(gè)科學(xué)的認(rèn)識與正確的判斷。評定板材沖壓性能的方法有直接試驗(yàn)法與間接試驗(yàn)法。 實(shí)物沖壓試驗(yàn)是最直接的板材沖壓性能的評定方法。利用實(shí)際生產(chǎn)設(shè)備與模具，在與生產(chǎn)完全相同的條件下進(jìn)行實(shí)際沖壓零件的性能評定，當(dāng)然能夠的最可靠的結(jié)果。但是，這種評定方法不具有普遍意義，不能作為行業(yè)之間的通用標(biāo)準(zhǔn)進(jìn)行信息的交流。 模擬試驗(yàn)是把生產(chǎn)中實(shí)際存在的沖壓成形方法進(jìn)行歸納與簡單化處理，消除許多過于復(fù)雜的因素，利用軸對稱的簡化了的成形方法，在保證試驗(yàn)中板材的變形性質(zhì)與應(yīng)力狀態(tài)都與實(shí)際沖壓成形相同的條件下進(jìn)行的沖壓性能的評定工作。為了保證模擬試驗(yàn)結(jié)果的可靠性與通用性，規(guī)定了私分具體的關(guān)于試驗(yàn)用工具的幾何形狀與尺寸、毛胚的尺寸、試驗(yàn)條件（沖壓速度、潤滑方法、壓邊力等）。 間接試驗(yàn)法也叫做基礎(chǔ)試驗(yàn)法。間接試驗(yàn)法的特點(diǎn)是：在對板材在塑性變形過程中所表現(xiàn)出的基本性質(zhì)與規(guī)律進(jìn)行分析與研究的基礎(chǔ)上，進(jìn)一步把它和具體的沖壓成形中板材的塑性變形參數(shù)聯(lián)系起來，建立間接試驗(yàn)結(jié)果（間接試驗(yàn)值）與具體的沖壓成形性能（工藝參數(shù)）之間的相關(guān)性。由于間接試驗(yàn)時(shí)所用試件的形狀與尺寸以及加載的方式等都不同于具體的沖壓成形過程，所以它的變形性質(zhì)和應(yīng)力狀態(tài)也不同于沖壓變形。因此間接試驗(yàn)所得的結(jié)果（試驗(yàn)值）并不是沖壓成形的工藝參數(shù)，而是可以用來表示板材沖壓性能的基礎(chǔ)性參數(shù)。Characteristics and Sheet Metal Forming1 The article overview Stamping is a kind of plastic forming process in which a part is produced by means of the plastic forming the material under the action of a die. Stamping is usually carried out under cold state, so it is also called stamping. Heat stamping is used only when the blank thickness is greater than 8100mm. The blank material for stamping is usually in the form of sheet or strip, and therefore it is also called sheet metal forming. Some non-metal sheets (such as plywood, mica sheet, asbestos, leather)can also be formed by stamping. Stamping is widely used in various fields of the metalworking industry, and it plays a crucial role in the industries for manufacturing automobiles, instruments, military parts and household electrical appliances, etc. The process, equipment and die are the three foundational problems that needed to be studied in stamping. The characteristics of the sheet metal forming are as follows: (1) High material utilization (2) Capacity to produce thin-walled parts of complex shape. (3) Good interchangeability between stamping parts due to precision in shapeand dimension. (4) Parts with lightweight, high-strength and fine rigidity can be obtained. (5) High productivity, easy to operate and to realize mechanization and automatization. The manufacture of the stamping die is costly, and therefore it only fits to mass production. For the manufacture of products in small batch and rich variety, the simple stamping die and the new equipment such as a stamping machining center, are usually adopted to meet the market demands. The materials for sheet metal stamping include mild steel, copper, aluminum, magnesium alloy and high-plasticity alloy-steel, etc.Stamping equipment includes plate shear punching press. The former shears plate into strips with a definite width, which would be pressed later. The later can be used both in shearing and forming. 2Characteristics of stamping forming There are various processes of stamping forming with different working patterns and names. But these processes are similar to each other in plastic deformation. There are following conspicuous characteristics in stamping: （1）The force per unit area perpendicular to the blank surface is not large but is enough to cause the material plastic deformation. It is much less than the inner stresses on the plate plane directions. In most cases stamping forming can be treated approximately as that of the plane stress state to simplify vastly the theoretical analysis and the calculation of the process parameters. （2）Due to the small relative thickness, the anti-instability capability of the blank is weak under compressive stress. As a result, the stamping process is difficult to proceed successfully without using the anti-instability device (such as blank holder). Therefore the varieties of the stamping processes dominated by tensile stress are more than dominated by compressive stress. （3）During stamping forming, the inner stress of the blank is equal to or sometimes less than the yield stress of the material. In this point, the stamping is different from the bulk forming. During stamping forming, the influence of the hydrostatic pressure of the stress state in the deformation zone to the forming limit and the deformation resistance is not so important as to the bulk forming. In some circumstances, such influence may be neglected. Even in the case when this influence should be considered, the treating method is also different from that of bulk forming. （4）In stamping forming, the restrain action of the die to the blank is not severs as in the case of the bulk forming (such as die forging). In bulk forming, the constraint forming is proceeded by the die with exactly the same shape of the part. Whereas in stamping, in most cases, the blank has a certain degree of freedom, only one surface of the blank contacts with the die. In some extra cases, such as the forming of the blank on the deforming zone contact with the die. The deformation in these regions are caused and controlled by the die applying an external force to its adjacent area. Due to the characteristics of stamping deformation and mechanics mentioned above, the stamping technique is different form the bulk metal forming: The importance or the strength and rigidity of the die in stamping forming is less than that in bulk forming because the blank can be formed without applying large pressure per unit area on its surface. Instead, the techniques of the simple die and the pneumatic and hydraulic forming are developed. Due to the plane stress or simple strain state in comparison with bulk forming, more research on deformation or force and power parameters has been done. Stamping forming can be performed by more reasonable scientific methods. Based on the real time measurement and analysis on the sheet metal properties and stamping parameters, by means of computer and some modern testing apparatus, research on the intellectualized control of stamping process is also in proceeding. It is shown that there is a close relationship between stamping forming and raw material. The research on the properties of the stamping forming, that is, forming ability and shape stability, has become a key point in stamping technology development, but also enhances the manufacturing technique of iron and steel industry, and provides a reliable foundation for increasing sheet metal quality. 3Categories of stamping forming Many deformation processes can be done by stamping, the basic processes of the stamping can be divided into two kinds: cutting and forming.Cutting is a shearing process that one part of the blank is cut from the other. It mainly includes blanking, punching, trimming, parting and shaving, where punching and blanking are the most widely used. Forming is a process that one part of the blank has some displacement from the other. It mainly includes deep drawing, bending, local forming, bulging, flanging, necking, sizing and spinning. In substance, stamping forming is such that the plastic deformation occurs in the deformation zone of the stamping blank caused by the external force. The stress state and deformation characteristic of the deformation zone are the basic factors to decide the properties of the stamping forming. Based on the stress state and deformation characteristics of the deformation zone, the forming methods can be divided into several categories with the same forming properties and be studied systematically.The deformation zone in almost all types of stamping forming is in the plane stress state. Usually there is no force or only small force applied on the blank surface. When is assumed that the stress perpendicular to the blank surface equals to zero, two principal stresses perpendicular to each other and act on the blank surface produce the plastic deformation of the material. Due to the small thickness of the blank, it is assumed approximately the two principal stresses distribute uniformly along the thickness direction. Based on this analysis, the stress state and the deformation characteristics of the deformation zone in all kinds of stamping forming can be denoted by the points in the coordinates of the plane principal stresses and the coordinates of the corresponding plane principal strains. 4Raw materials for stamping formingThere are a lot of raw materials used in stamping forming, and the properties of these materials may have large difference. The stamping forming can be succeeded only by determining the stamping method, the forming parameters and the die structures according to the properties and characteristics of the raw materials. The deformation of the blank during stamping forming has been investigated quite thoroughly. The relationships between the material properties decided by the chemistry component and structure of the material and the stamping forming has been established clearly. Not only the proper material can be selected based on the working condition and usage demand, but also the new material can be developed according to the demands of the blank properties during processing the stamping part. This is an important domain in stamping forming research. The research on the material properties for stamping forming is as follows: （1）Definition of the stamping property of the material. （2）Method to judge the stamping property of the material, find parameters to express the definitely material property of the stamping forming, establish the relationship between the property parameters and the practical stamping forming, and investigate the testing methods of the property parameters. （3）Establish the relationship among the chemical component, structure, manufacturing process and stamping property. The raw materials for stamping forming mainly include various metals and nonmetal plate. Sheet metal includes both ferrous and nonferrous metals. Although a lot of sheet metals are used in stamping forming, the most widely used materials are steel, stainless steel, aluminum alloy and various composite metal plates. 5Stamping forming property of sheet metal and its assessing methodThe stamping forming property of the sheet metal is the adaptation capability of the sheet metal to stamping forming. It has crucial meaning to the investigation of the stamping forming property of the sheet metal. In order to produce stamping forming parts with most scientific, economic and rational stamping forming process and forming parameters, it is necessary to understand clearly the properties of the sheet metal, so as to utilize the potential of the sheet metal fully in the production. On the other hand, to select plate material accurately and rationally in accordance with the characteristics of the shape and dimension of the stamping forming part and its forming technique is also necessary so that a scientific understanding and accurate judgment to the stamping forming properties of the sheet metal may be achieved. There are direct and indirect testing methods to assess the stamping property of the sheet metal.Practicality stamping test is the most direct method to assess stamping forming property of the sheet metal. This test is done exactly in the same condition as actual production by using the practical equipment and dies. Surely, this test result is most reliable. But this kind of assessing method is not comprehensively applicable, and cannot be shared as a commonly used standard between factories. The simulation test is a kind of assessing method that after simplifying and summing up actual stamping forming methods, as well as eliminating many trivial factors, the stamping properties of the sheet metal are assessed, based on simplified axial-symmetric forming method under the same deformation and stress states between the testing plate and the actual forming states. In order to guarantee the reliability and generality of simulation results, a lot of factors are regulated in detail, such as the shape and dimension of tools for test, blank dimension and testing conditions(stamping velocity, lubrication method and blank holding force, etc).Indirect testing method is also called basic testing method its characteristic is to connect analysis and research on fundamental property and principle of the sheet metal during plastic deformation, and with the plastic deformation parameters of the sheet metal in actual stamping forming, and then to establish the relationship between the indirect testing results(indirect testing value) and the actual stamping forming property (forming parameters). Because the shape and dimension of the specimen and the loading pattern of the indirect testing are different from the actual stamping forming, the deformation characteristics and stress states of the indirect test are different from those of the actual one. So, the results obtained form the indirect test are not the stamping forming parameters, but are the fundamental parameters that can be used to represent the stamping forming property of the sheet metal.