壓圈沖壓模具設(shè)計(jì)【落料沖孔級進(jìn)?！?/h1>
壓圈沖壓模具設(shè)計(jì)【落料沖孔級進(jìn)?！?落料沖孔級進(jìn)模,壓圈沖壓模具設(shè)計(jì)【落料沖孔級進(jìn)?！?沖壓,模具設(shè)計(jì),沖孔,級進(jìn)模
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班級 姓名 學(xué)號
課題名稱3： 壓圈沖模設(shè)計(jì)
工件圖：其形狀和尺寸如下頁圖所示。板厚為1mm，板材為10，工件精度IT11。
設(shè)計(jì)要求：
1. 繪制該工件制作所需的模具總裝圖一張。
2. 繪制該模具凸模、凹模及另選兩個(gè)零件的零件圖四張。
3. 編寫一份設(shè)計(jì)計(jì)算說明書。
內(nèi)容包括：沖壓工藝性分析，工藝方案制定，排樣圖設(shè)計(jì)，總的沖壓力計(jì)算及壓力中心計(jì)算，確定設(shè)備類型，刃口尺寸計(jì)算，彈簧、橡膠件的計(jì)算和選用，凸模、凹?；蛲拱寄＝Y(jié)構(gòu)設(shè)計(jì)以及其他沖模零件的結(jié)構(gòu)設(shè)計(jì)，填寫沖壓工藝卡片。
指導(dǎo)老師 時(shí)間
第1章 緒論 2
1.1沖壓工藝概述 2
1.1 沖壓工藝簡介 2
1.2工藝方案的確定 2
1.2.1 錫青銅QSn4-4-2.5的性能 2
1.2.2 方案確定 3
第2章 復(fù)合沖壓模具設(shè)計(jì)與計(jì)算 3
2.1.1沖裁件的工藝性分析 3
2.1.2 確定工藝方案及模具形式 3
2.2凹凸模間隙的選擇 3
2.2.1沖裁間隙的分類 4
2.2.6 確定合理間隙的理論依據(jù) 4
2.2.7合理間隙的選擇 4
2.3凹凸模制造方法及刃口尺寸的計(jì)算 5
2.3.1 凹凸模的制造方法 5
2.3.2凹凸模刃口尺寸的計(jì)算 5
2.4排樣 7
2.4.1排樣的意義 7
2.4.2排樣的方法 7
2.4.3搭邊、進(jìn)距計(jì)算 8
2.5沖裁力的計(jì)算及選擇壓力機(jī) 10
2.5.1沖裁力的計(jì)算 10
2.5.2選擇壓力機(jī) 13
2.6沖裁模主要零件的設(shè)計(jì) 14
2.6.1凹模設(shè)計(jì) 14
2.6.2 凹凸模設(shè)計(jì) 16
2.6.3沖孔凸模的設(shè)計(jì) 16
2.6.4定位零件的確定 17
2.6.5卸料與推料裝置 17
2.6.6模座、導(dǎo)向零件 18
2.6.7連接與固定零件 18
參考文獻(xiàn) 19
第1章 緒論
1.1沖壓工藝概述
1.1 沖壓工藝簡介
沖壓是塑性加工的基本方法之一，它是利用安裝在壓力機(jī)上的模具，在室溫下對材料施加壓力使其產(chǎn)生變形或分離，從而獲得具有一定形狀、尺寸和精度的制件的一種壓力加工方法。因?yàn)樗饕糜诩庸ぐ辶现萍?，所以也稱板料沖壓。在機(jī)械制造中是一種高效率的加工方式。
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。
1.2工藝方案的確定
1.2.1 錫青銅QSn4-4-2.5的性能
QSn4-4-2.5經(jīng)退火處理后，其抗剪強(qiáng)度為125～550MPa，其抗拉強(qiáng)度為294～490 MPa，其伸長率為5%～35%，適合于做沖壓材料。
1.2.2 方案確定
方案一：沖孔—落料
方案二：落料，沖孔(復(fù)合)
方案三：落料，沖孔(連續(xù))
方案一：單工序模，先沖孔再落料保證一定的精度，但主要適用于生產(chǎn)量較小或單件生產(chǎn)，生產(chǎn)率較低，且多了一模具，生產(chǎn)周期長。
方案二：避免了多次定位的結(jié)構(gòu)，并在沖裁過程中可以壓料，工件較平整，較單工序?？s短生產(chǎn)周期。
方案三: 根據(jù)生產(chǎn)量，模具可以采用連續(xù)模，但是連續(xù)模的結(jié)構(gòu)復(fù)雜，對制造精度的要求高，連續(xù)模比復(fù)合模比較生產(chǎn)周期長，成本高，維護(hù)也困難。
經(jīng)過比較分析壓圈的沖壓模具設(shè)計(jì)采用方案二。
第2章 復(fù)合沖壓模具設(shè)計(jì)與計(jì)算
2.1 沖裁件的工藝設(shè)計(jì)
2.1.1沖裁件的工藝性分析
沖裁件的工藝性分析是指沖裁件對沖裁的適應(yīng)性，即沖裁件的形狀結(jié)構(gòu)、尺寸的大小及偏差等是否符合加工的工藝要求。沖裁件的工藝性是否合理對沖裁件的質(zhì)量、模具的壽命和生產(chǎn)率有很大影響。
壓圈形狀簡單、對稱，是由圓弧和直線組成的，沖裁件內(nèi)外所能達(dá)到的經(jīng)濟(jì)精度為IT11，該零件的精度要求能夠在沖裁加工中得到保證．其生產(chǎn)批量等情況，也均符合沖裁的工藝要求，故經(jīng)壓圈符合沖裁工藝要求。
2.1.2 確定工藝方案及模具形式
綜上分析，沖裁件精度要求不高，尺寸不大，形狀不復(fù)雜生產(chǎn)量為大批量生產(chǎn)，材料厚度，t=0.2mm,且孔位精度無要求，采用手工送料、剛性卸料、自動漏料、導(dǎo)料銷導(dǎo)料的沖孔落料復(fù)合沖裁模具結(jié)構(gòu)形式。
2.2凹凸模間隙的選擇
沖裁間隙指凸、凹模刃口間隙的距離。沖裁間隙是沖壓工藝和模具設(shè)計(jì)中的重要參數(shù)，它直接影響沖裁件的質(zhì)量、模具壽命和力能的消耗，應(yīng)根據(jù)實(shí)際情況和需要合理的選用。沖裁間隙有單面間隙和雙面間隙之分。
2.2.1沖裁間隙的分類
根據(jù)沖裁件尺寸精度、剪切質(zhì)量、模具壽命和力能消耗等主要因素，將金屬材料沖裁間隙分成三種類型：Ⅰ類（小間隙），Ⅱ類（中等間隙），Ⅲ類（大間隙）。
2.2.6 確定合理間隙的理論依據(jù)
由以上分析可見，凸、凹模對沖裁件質(zhì)量、沖裁力、模具壽命等都有很大的影響。因此，在設(shè)計(jì)和制造模具時(shí)有一個(gè)合理的間隙值，以保證沖裁件的斷面質(zhì)量好，尺寸精度高，所需沖裁力小，模具壽命高。生產(chǎn)中常選用一個(gè)適當(dāng)?shù)姆秶鳛楹侠黹g隙。這個(gè)范圍的最小值稱為最小合理間隙Zmin,最大值稱為最大合理間隙Zmax。設(shè)計(jì)與制造新模具時(shí)采用最小合理間隙值。
確定合理間隙的理論根據(jù)是以凸、凹模刃口處產(chǎn)生的裂紋相重合為依據(jù)。可以計(jì)算得到合理間隙值，計(jì)算公式如下：
Z=2t(1- )tanβ
由上式可看出，間隙z與材料厚度t、相對切入深度h0/t及破裂角β有關(guān)。對硬而脆的材料，h0/t有較小值時(shí)，則合理間隙值較大。對軟而韌的材料，h0/t有較大值，則合理間隙值較小。板厚越大，合理間隙越大。
由于理論計(jì)算在生產(chǎn)中不便使用，故目前廣泛使用的是經(jīng)驗(yàn)數(shù)據(jù)。
2.2.7合理間隙的選擇
表2-1常用金屬材料的沖裁初始間隙（雙面）
材料
厚度
低碳鋼，銅，紫銅，鋁
中碳鋼，杜拉銅
高碳鋼，不銹鋼
最小值
△z
最小值
△z
最小值
△z
0.2
0.010
+0.010
0.012
+0.010
0.014
+0.010
0.3
0.015
0.018
0.021
0.4
0.020
0.024
0.028
0.5
0.025
0.030
0.035
0.6
0.030
+0.020
0.036
+0.020
0.042
+0.020
0.7
0.035
0.042
0.049
zmax=zmin＋△z，由表可知，此復(fù)合模的最小雙面間隙為zmin=0.010mm，最大雙面間隙為zmax=0.020mm。
2.3凹凸模制造方法及刃口尺寸的計(jì)算
2.3.1 凹凸模的制造方法
凸、凹模的加工方法有兩種：凸、凹模分開加工法和凸、凹模配合加工方法。
當(dāng)凸、凹模分開加工時(shí)，模具具有互換性，便于模具成批量生產(chǎn)，但精度要求很高，制造困難，相應(yīng)的會增加加工成本。凸、凹模配合加工適合于較復(fù)雜的、非圓形的模具，制造簡單，成本低。
鑒于上述分析，就零件圖所需的凸、凹模宜采用凸、凹模配合加工。
2.3.2凹凸模刃口尺寸的計(jì)算
模具刃口尺寸精度等級是影響沖裁件尺寸精度等級的主要因素，模具的合理間隙值也是靠模具刃口尺寸及其精度來保證的。因此，在確定凹、凸模工作部分尺寸及其制造精度時(shí)，必須主要考慮到?jīng)_裁變形規(guī)律、沖裁件精度等級、模具磨損和制造特點(diǎn)等。
(1)落料時(shí)，先確定凹模工作部分尺寸，其大小應(yīng)取接近于或等于工件的最小極限尺寸，以保證凹模磨損到一定尺寸范圍內(nèi)，仍能沖出合格工件。凸模公稱尺寸應(yīng)比凹模公稱尺寸小一個(gè)合理間隙值。
(2)沖孔時(shí)，先確定凸模工作部分尺寸，其大小應(yīng)取接近或等于孔的最大極限尺寸，以保證凸模磨損到一定尺寸范圍內(nèi)，仍能沖出合格工件。凹模公稱尺寸應(yīng)比凸模公稱尺寸大一個(gè)合理間隙值。
(3)對于落料件，一般標(biāo)注單向負(fù)公差。假定工件的尺寸為D，工件公差為△，則工件尺寸就是。沖孔件的公差一般為單向正公差，假定沖孔件的公稱尺寸為d，工件公差為△，則沖孔件公差為。若工件尺寸標(biāo)注有正負(fù)公差，則應(yīng)將正負(fù)偏差換成上述要求的等價(jià)的正公差或負(fù)公差，若工件沒有標(biāo)注公差，則工件公差按國家標(biāo)準(zhǔn)非配合尺寸的IT14級來處理。
凹凸模配合加工，是指先加工凸模（或凹模），然后根據(jù)制好的凸模（或凹模）的實(shí)際尺寸，配做凹模（或凸模），在凹模（或凸模）上修出最小合理間隙值。其方法是把先加工出的凸模（或凹模）做為基準(zhǔn)件，它的工作部分的尺寸作為基準(zhǔn)尺寸，而與它配做的凹模（或凸模），只需在圖紙上標(biāo)明相應(yīng)部分的凸模公稱尺寸（或凹模公稱尺寸），注明“××尺寸按凸模（或凹模）配做，每邊保證間隙××”。這樣基準(zhǔn)件的制造公差δp（或δd）的大小就不在受凸、凹模間隙大小的限制，是模具制造容易。一般基準(zhǔn)件的制造公差δp（或δd）=。
1.落料
落料時(shí)應(yīng)以凹模為基準(zhǔn)，在后配做凸模。落料凹模磨損后，刃口尺寸的變化有增大、減小、不變?nèi)星闆r。
凹模磨損后增尺寸增大時(shí)，凹模尺寸按公式 計(jì)算，其中系數(shù)x按IT11精度等級取值x=0.75。
尺寸Φ55在磨損后增大，△=0.19mm，化為55.095
= (55.095－0.75×0.19)
= 54.9525
尺寸R10在磨損后增大，△=0.09mm，化為10.045
=(10.045－0.75×0.09)
= 9.9775
2.沖孔
落料時(shí)應(yīng)以凸模為基準(zhǔn)，然后配做凹模。落料凸模磨損后，刃口尺寸的變化有增、大減、小不、變?nèi)星闆r。
凸模磨損后尺寸減小時(shí)，凸模尺寸按公式計(jì)算，其中系數(shù)x
按IT11精度等級取值x=0.75。
尺寸35在磨損后減小，△=0.16mm,化為34.92
= (34.92+0.75×0.16)
=35.04
尺寸Φ8在磨損后減小，△=0.09mm,化為7.955
=(7.955+0.75×0.09)
=8.0225
尺寸6在磨損后減小，△=0.09mm,化為5.955
=(5.955+0.75×0.09)
=6.0225
尺寸2在磨損后減小，△=0.06mm,化為1.97
=(1.97+0.75×0.06)
=2.015
凸模磨損后尺寸不變的有70，按計(jì)算
2.4排樣
2.4.1排樣的意義
在大量和大批生產(chǎn)時(shí)，原始毛坯材料在沖壓零件的成本中占60%以上，因此節(jié)約材料和減少廢料（既材料的經(jīng)濟(jì)利用率）具有很重要的意義。沖裁件在條料上的布置方法稱為排樣。
2.4.2排樣的方法
同一個(gè)工件，可有幾種不同的排樣方法。采用最佳排樣方法，應(yīng)使工藝廢料最少，材料利用率高。根據(jù)零件外形特征，排樣的形式可分為直排、斜排、對排、混合排、多排及沖裁搭邊等。
根據(jù)零件的形狀特點(diǎn)，選用如下的排樣方式，每次沖壓過程沖出一個(gè)零件。
排樣方式與零件在板料上的排布如下圖：
圖2-1零件排布圖
2.4.3搭邊、進(jìn)距計(jì)算
1.搭邊
排樣時(shí)工件與工件之間及工件與條料之間留下的余料稱為搭邊及側(cè)搭邊。
搭邊值要合理確定。塔邊值過大，材料利用率低。搭邊值過小，在沖裁中將會被拉斷，造成送料困難，且使工件產(chǎn)生毛刺，有時(shí)還會拉入凸模和凹模間隙中，損壞模具刃口，降低模具壽命。
表2-2 搭邊值的經(jīng)驗(yàn)值
卸料板形式
條料厚度
搭邊值
a
a1
彈
性
卸
料
板
>0.25
1.5～2.5
1.8～2.6
>0.25～0.5
1.2～2.2
1.5～2.5
＞0.5～1.0
1.5～2.5
1.8～2.6
＞1.0～1.5
1.8～2.8
2.2～3.2
＞1.5～2.0
2.0～3.0
2.4～3.4
固
定
卸
料
板
0～0.25
2.2～3.2
＞0.25～0.5
2.0～3.0
＞0.5～1.0 1.01.01.0
1.5～2.5
＞1.0～1.5
1.8～2.8
＞1.5～2.0
2.0～3.0
搭邊值一般由經(jīng)驗(yàn)確定，如表2-2所示。
根據(jù)表，可取a=1.8mm a1=2.5mm。
排樣方式與搭邊值決定后，條料的寬度與進(jìn)距也可以決定。
條料寬度的確定與模具是否采用側(cè)壓裝置或側(cè)刃有關(guān)。
本設(shè)計(jì)采用無側(cè)壓裝置，其條料寬度的確定；條料在送進(jìn)過程中可能沿導(dǎo)料板的一側(cè)，也可能沿另一側(cè)，條料導(dǎo)向面的變化將使側(cè)搭邊值減小，為保證最小側(cè)搭邊值，條料寬度應(yīng)加大些：
條料的寬度的計(jì)算：
B=
式中 B—— 條料的公稱寬度，mm
D——垂直于送料方向的工件尺寸,mm
a1——側(cè)搭邊,mm
b0——條料與導(dǎo)料板間的間隙,見表2-3
——條料寬度的公差，見表2-3
表2-3剪切條料公差及導(dǎo)料板與條料間的間隙值（mm）
0～1.0
＞1.0～2.0
＞2.0～3.0
＞3.0～5.0
Δ
b0
Δ
b0
Δ
b0
Δ
b0
～50
0.4
0.1
0.5
0.2
0.7
0.4
0.9
0.6
>50～100
0.5
0.6
0.8
1.0
>100～150
0.6
0.2
0.7
0.3
0.9
0.5
1.1
0.7
>150～220
0.7
0.8
1.0
1.2
B=[D+2(a+Δ)+b0] =[55+2×(2.2+0.5)+0.1]
=60.5mm
條料的寬度的公稱尺寸為B=60.5mm。
2.進(jìn)距
進(jìn)距是每次將條料送入模具進(jìn)行沖裁的距離，進(jìn)距的計(jì)算與排樣方式有關(guān)，進(jìn)距是決定擋料銷位置的依據(jù)。
此工序?yàn)槁淞蠜_孔復(fù)合模，零件的進(jìn)距A的計(jì)算公式為：
A＝B + a
式中 B—平行于送料方向工件的寬度；
a—沖裁件之間的搭邊值。
進(jìn)距
A=B＋a=62.87＋1.8
=64.67mm
2.5沖裁力的計(jì)算及選擇壓力機(jī)
2.5.1沖裁力的計(jì)算
1.計(jì)算沖裁力
計(jì)算沖裁力的目的是為了選用合適的壓力機(jī)、設(shè)計(jì)模具和檢驗(yàn)?zāi)＞邚?qiáng)度。壓力機(jī)的噸位必須大于沖裁力。
一般平刃口模具沖裁時(shí)，沖裁力可按下式計(jì)算：
式中 P—— 沖裁力，N；
F—— 沖切斷面積，mm2；
L—— 沖裁周邊長度，mm;
t—— 材料厚度，mm；
—— 材料抗剪強(qiáng)度，MPa；08鋼的抗剪強(qiáng)度為216～304MPa，取300MPa；
K—— 安全系數(shù)，一般取K＝1.3，考慮到模具刃口的磨損，凸凹模間隙的波動，材料機(jī)械性能的變化，材料厚度及偏差等因素。
在沖裁高強(qiáng)度材料或厚度大、周邊長的工件時(shí)，所需的沖裁力較大。如果超過現(xiàn)有壓力機(jī)噸位，就必須采取措施降低沖裁力，主要有斜刃模具沖裁、階梯模具沖裁和加熱模具沖裁幾種方法。
1) 計(jì)算
= =
=18521.36N
2)計(jì)算
==
=7983.85N
P=+=18521.36+7983.85
=26505.21N27KN
2.卸料力與推件力的計(jì)算
沖裁結(jié)束后，由于彈性變形的恢復(fù)，會使工件卡緊在凸?；虬寄Ｉ?，必須施加外力，將其取下。
卸料力：將緊箍在凸模上的料卸下所需的力
推件力：將卡在凹模中的工件推出所需的力
表2-4 卸料力、推件力的因數(shù)
沖裁材料
K卸
K推
K頂
紫銅黃銅
0.02～0.06
0.03～0.09
鋁、鋁合金
0.025～0.08
0.03～0.07
鋼
材 料
厚 度
mm
～0.1
＞0.1～0.5
＞0.5～2.5
＞2.5～6.5
＞6.5
0.06～0.075
0.045～0.055
0.04～0.05
0.03～0.04
0.02～0.03
0.10
0.065
0.050
0.045
0.025
0.14
0.08
0.06
0.05
0.03
卸料力和推件力是由壓力機(jī)和模具的卸料與推件裝置獲得的。在選擇壓力機(jī)噸位和設(shè)計(jì)模具時(shí)，要根據(jù)模具結(jié)構(gòu)來考慮卸料力、推件力與頂件力的大小，并作必要的計(jì)算。影響這些力的因素較多，生產(chǎn)中，常用下列經(jīng)驗(yàn)公式計(jì)算：
、—— 卸料因數(shù)、推件因數(shù)（其值見表2-4）；
P ——沖裁力， N ；
n —— 卡在凹?？變?nèi)的工件數(shù)，n＝h/t(h為凹
模刃口直高度，t為工件材料厚度)。
卸料力
=0.04×27=1.08KN
推件力
=0.05×27=1.35KN
3.壓力中心的確定
沖裁力合力的作用點(diǎn)稱為沖模壓力中心。
沖模壓力中心的確定過程如下：
1）按比例繪出凸模工作部分的外形；
2）0任意選定坐標(biāo)軸X－Y。坐標(biāo)軸的選定應(yīng)使計(jì)算簡便；
3）計(jì)算各圖形輪廓周長：L1、 L2、 L3、 L4… Ln(代替沖裁力)，以及各圖形重心坐標(biāo)：(x1,y1)、 (x2,y2)、 (x3,y3)、 (x4,y4)… (xn,yn)；
4）根據(jù)“合力對某軸的力矩等于各分力對同軸力矩的和”的力學(xué)原理，得到?jīng)_模壓力中心坐標(biāo)計(jì)算公式為：
此外還可以利用CAD，PRO/E等繪圖軟件分析壓力中心，經(jīng)CAD分析可知，壓力中心如圖2-2所示：
圖2-2壓力中心
4.沖裁功的計(jì)算
A≈0.5Pt
式中 A---成形的過程的功，Nm
P---成形工藝力和輔助工藝力之和,KN
t---沖裁料厚度，mm
P=P+P+=27+1.04+1.35=29.39kN30KN
沖裁功
A=0.5Pt=0.5×30×0.2=3N·m
2.5.2選擇壓力機(jī)
1.壓力機(jī)的選擇原理
沖壓設(shè)備的選擇主要是根據(jù)沖壓工藝性質(zhì)、生產(chǎn)批量大小、沖壓件的形狀、尺寸及精度要求等因素來決定的。沖壓生產(chǎn)中常用的設(shè)備種類很多，選用設(shè)備時(shí)主要應(yīng)考慮下述因素：
(1).沖壓設(shè)備的類型和工作形式是否適用于應(yīng)完成的工序，是否符合安全生產(chǎn)和環(huán)保的要求。
(2).沖壓設(shè)備的壓力和功率是否滿足應(yīng)完成任務(wù)工序的要求。
(3).沖壓設(shè)備裝模高度、工作臺尺寸、行程等是否適合應(yīng)完成工序所所使用的模具。
(4).沖壓設(shè)備的行程次數(shù)是否滿足生產(chǎn)率的要求等。
3.選擇壓力機(jī)
一般情況下所選壓力機(jī)的標(biāo)稱壓力大于或等于成型工藝力和輔助工藝力總和的1.3倍，對于工作行程小于標(biāo)稱壓力行程的工序也可直按壓力機(jī)的標(biāo)稱壓力選擇設(shè)備。
因此壓力機(jī)的標(biāo)準(zhǔn)壓力必須大于沖裁力P=27KN。根據(jù)以上參數(shù)選用J23-6.3型開式壓力機(jī)，其的部分技術(shù)參數(shù)如下表所示：
表2-5J23-6.3型開式壓力機(jī)部分技術(shù)參數(shù)
公稱壓力/KN
滑塊行程/mm
行程次數(shù)/（次/min）
最大閉合高度/mm
閉合高度調(diào)節(jié)量/mm
63
35
170
170
40
工作臺尺寸/mm
模柄孔尺寸/mm
電動機(jī)功率/kW
前后
左右
直徑
深度
0.75
200
310
φ30
55
由壓力機(jī)的參數(shù)可知壓力機(jī)的封閉高度
Hmax=170mm Hmin=130mm
模具的封閉高度：
(Hmax-5)mm H (Hmin+10)mm
(170-5)≥H≥(130+10)
165≥H≥140
2.6沖裁模主要零件的設(shè)計(jì)
2.6.1凹模設(shè)計(jì)
1.凹模的刃口形式
凹模的刃口形式有直壁刃口凹模(如圖2-3a、b)和錐形刃口凹模（如圖2-3c、d）。
圖2-3 凹模的刃口形式
a)型一般適用于非圓形工件。
b)型適于圓形工件、需將工件或廢料頂出的模具或復(fù)合沖裁模。
錐形刃口凹模刃口強(qiáng)度較低，刃口尺寸在修磨后有所增大，但一般對工件尺寸和凹模壽命影響不大。工件或廢料很容易從凹?？變?nèi)落下，孔內(nèi)不易積聚工件或廢料，孔壁所受的摩擦力及脹裂力小，所以凹模的磨損及每次修磨量小。錐形刃口凹模適用于形狀簡單、公差等級要求不高、材料較薄的工件。
沖孔落料復(fù)合模凹模采用直壁刃口形式（b）。
圖中凹模孔型參數(shù)如下表所示：
表2-6 凹?？湛谥饕獏?shù)
材料厚度t/mm
主要參數(shù)
h/mm
α
β
<0.5
≥4
15＇
2°
0.5～1
≥5
1.0～2.5
≥6
2.凹模輪廓尺寸
凹模的輪廓尺寸應(yīng)保證有足夠的強(qiáng)度和剛度。凹模的輪廓尺寸，因其結(jié)構(gòu)形式不一，受力狀態(tài)比較復(fù)雜，目前還不能用理論計(jì)算方法確定。在實(shí)際生產(chǎn)中，一般根據(jù)沖裁材料的厚度，按經(jīng)驗(yàn)公式作概略的計(jì)算。凹模的輪廓尺寸應(yīng)保證有足夠的強(qiáng)度和剛度。目前還不能用理論公式計(jì)算來確定，一般情況凹模的輪廓尺寸可按如下的經(jīng)驗(yàn)公式確定。
凹模厚度： H=kb（須≥15mm）
凹模壁厚： C≥（1.5～2.0）H（須≥30～40mm）
凹模刃口線為直線時(shí)，取C≥1.5H；若為尖端狀或具有復(fù)雜形狀時(shí)，取C≥2.0H；
式中 b——沖裁件的最大外形尺寸,mm
k——系數(shù),查表2-7
表2-7系數(shù)K值
b/mm
材料厚度/mm
0.5
1
2
3
>3
50～100
0.2
0.22
0.28
0.35
0.42
100～200
0.15
0.18
0.2
0.24
0.3
板料的厚度t=0.2mm，取k=0.2，則凹模厚度：
H=Kb=0.2×80.62=16.124mm 取H=17mm
凹模壁厚
C≥（1.5～2.0）H=25.5～35mm 取C=35mm
則模具的外形尺寸為
B=2C+b=70+55=125mm
B=2C+b=70+80.62=150.62mm 取B=160mm
選取沖壓模具凹模尺寸為：160mm×125mm×17mm。
凹模固定螺釘?shù)拇笮∪缦卤硭荆?
表2-8凹模厚度與螺釘?shù)拇笮?
凹模厚度/mm
≤13
>13～19
>19～25
>25～32
>32
螺孔大小/mm
M4、M5
M5、M6
M6、M10
M8、M10
M10、M12
根據(jù)表2-8選用M10內(nèi)六角螺釘。
2.6.2 凹凸模設(shè)計(jì)
凸模固定端與模座直接接觸時(shí)，當(dāng)單位壓力超過模座材料的許用壓力時(shí)，模座表面
就會損傷，為此應(yīng)在凸模頂端與模座之間加一個(gè)淬硬墊板。通常凸模固定端面的壓力超過80～90MPa時(shí)（模座材料采用鑄鐵）或壓力超過（80～120MPa(模座材料為Q235)時(shí)需要加墊板。
沖壓過程中的凹凸模最小壁厚為a=5mm，查表2-10可知最小壁厚為3.8mm，a=5≥0.2mm，因此凹凸模壁厚滿足要求
表2-10凸凹模最小壁厚 (mm)
料厚/mm
0.4
0.6
0.8
0.9
1.0
1.2
1.5
最小壁厚a/mm
1.4
1.8
2.3
2.5
2.7
3.2
3.8
最小直徑D/mm
15
18
21
2.6.3沖孔凸模的設(shè)計(jì)
1.凸模長度的計(jì)算
凸模的長度
L≤H1+H2+H3
H1——凹模的高度，mm;
H2——凸模固定板的高度,mm;
H3——增加長度,mm。
L=10+17+12=39mm
2.凸模強(qiáng)度的校核
一般情況下，凸模的強(qiáng)度是足夠的，所以沒必要作強(qiáng)度校驗(yàn)。又因本設(shè)計(jì)中的凸模直徑大而長度短，故凸模強(qiáng)度不再校驗(yàn)。
2.6.4定位零件的確定
定位零件(裝置)的作用是保證坯料的正確送進(jìn)及在沖模中的正確位置。
使用條料時(shí)，保證條料送進(jìn)導(dǎo)向的零件有導(dǎo)料板、導(dǎo)料銷等。導(dǎo)料銷一般用兩個(gè)，
壓裝在凹模上的固定式，在卸料板上的為活動式。導(dǎo)料銷多用于單工序模和復(fù)合模。
擋料銷是用來限制條料送進(jìn)步距，抵住條料的搭邊或工件輪廓的零件，起定位作用。擋料銷分為固定擋料銷和活動擋料銷。
為保證導(dǎo)料銷與凹模刃口間的距離，導(dǎo)料銷選用擋料銷的形式。
圖2-5 固定擋料銷結(jié)構(gòu)尺寸
查相關(guān)手冊，取h=3mm，D=10mm，d=4mm，L=13mm。
2.6.5卸料與推料裝置
1.卸料裝置
卸料裝置的主要作用是把材料由凸模上卸下，有時(shí)也可作壓料板，以防止材料變形，并能幫助送料導(dǎo)向和保護(hù)凸模。卸料裝置有剛性與彈性卸料板和廢料切刀等形式。固定卸料板結(jié)構(gòu)簡單，但卸料力大。彈性卸料板卸料力小，一般用于材料厚度小于等于1.5mm的沖裁。
卸料半選用彈性卸料板，彈性材料選擇橡膠。卸料板的厚度值與凹模寬度有關(guān)，其值如下：
表2-11卸料板厚度的選擇 mm
材料厚度t/mm
卸料板寬度B/mm
≤50
>50～80
>80～125
>125～200
>200
≤0.8
8
10
12
14
16
>0.8～1.5
10
12
14
16
18
則卸料板的厚度選擇14mm。
2.推件裝置與打料裝置
頂件裝置則大多采用彈性的，通常由頂桿、頂件塊和裝在下模底下的彈頂件器等所組成。彈頂器的頂件力有彈簧或橡皮所產(chǎn)生，這種結(jié)構(gòu)的頂件力容易調(diào)節(jié)，工作可靠，沖裁件的平直度高。但在操作中，彈簧或橡皮受到經(jīng)常變化的壓力，產(chǎn)生疲倦，彈性容易減弱。
頂件裝置采用彈簧頂件裝置，頂件器在自由狀態(tài)下高出凹模面0.2～0.5mm。
打料裝置由打、打板等組成，留在凹凸模中的沖孔廢料由打桿推出。
2.6.6模座、導(dǎo)向零件
1.模座
模座選用中間導(dǎo)柱標(biāo)準(zhǔn)模座，上模座厚度H1=35mm，下模座厚度H2=40mm。
2.導(dǎo)向零件
導(dǎo)向零件是指上、下模的導(dǎo)向裝置零件。對于生產(chǎn)量大要求模具壽命長、工件精度高的沖裁模，一般采用導(dǎo)向模具，以保證上、下模的精確導(dǎo)向。
導(dǎo)向裝置結(jié)構(gòu)有滑動導(dǎo)柱導(dǎo)套結(jié)構(gòu)和滾動導(dǎo)柱到套結(jié)構(gòu)?；瑒訉?dǎo)柱導(dǎo)套結(jié)構(gòu)是常用的結(jié)構(gòu)，這種結(jié)構(gòu)加工方便，易于標(biāo)準(zhǔn)化，但承受側(cè)壓力的能力差?；瑒訉?dǎo)柱導(dǎo)套結(jié)構(gòu)四角、后側(cè)、中間、對角導(dǎo)柱導(dǎo)套結(jié)構(gòu)。
2.6.7連接與固定零件
1.模柄
中小型沖模通過模柄將上模固定在壓力機(jī)的滑快上，常用的形式有壓入式、凸緣模柄、通用模柄、浮動模柄。
壓入式：與上模座孔為過渡配合：加銷釘防止轉(zhuǎn)動。
凸緣模柄：用3～4各螺釘固定在上模座的窩孔內(nèi)，多用于大型模具，有A、B、C三種型號。
通用模柄：凸模直接裝入模柄孔中，有螺釘壓緊，便于更換凸模。
浮動模柄：允許模柄少許傾斜，可以減少滑塊誤差對模具導(dǎo)向精度的影響
采用壓入式模柄，與模座的配合過度配合，B40×100 JB/T7646.1
2.凸模墊板與固定板
（1）.固定板 凸模固定板將凸模固定在上模座上，其輪廓尺寸要考慮凸模安裝孔、螺釘和銷釘孔的設(shè)置。用固定板將凸模固定在模座上，固定板孔與凸模采用過渡配合。
壓裝后其端面磨平，以保證沖模的垂直度。
凸凹模固定板：160×125×8
沖孔凸模固定板：160×125×8
（2）.螺釘與銷釘 螺釘與銷釘用于安裝時(shí)的固定與定位。銷釘一般用兩個(gè)，螺釘?shù)拇笮「鶕?jù)凹模厚度進(jìn)行選擇。
參考文獻(xiàn)
[1] 吳詩惇主編. 沖壓工藝及模具設(shè)計(jì) 2002年. 第一版. 西北工業(yè)大學(xué)出版社
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INEEL/CON-2000-00104PREPRINTSpray-Formed Tooling for Injection Molding andDie Casting ApplicationsK. M. McHughB. R. WickhamJune 26, 2000 June 28, 2000International Conference on Spray Depositionand Melt AtomizationThis is a preprint of a paper intended for publication in ajournal or proceedings. Since changes may be madebefore publication, this preprint should not be cited orreproduced without permission of the author.This document was prepared as a account of worksponsored by an agency of the United States Government.Neither the United States Government nor any agencythereof, or any of their employees, makes any warranty,expressed or implied, or assumes any legal liability orresponsibility for any third partys use, or the results ofsuch use, of any information, apparatus, product orprocess disclosed in this report, or represents that itsuse by such third party would not infringe privatelyowned rights. The views expressed in this paper arenot necessarily those of the U.S. Government or thesponsoring agency.B E C H T E L B W X T I D A H O , L L C1Spray-Formed ToolingFor Injection Molding and Die Casting ApplicationsKevin M. McHugh and Bruce R. WickhamIdaho National Engineering and Environmental LaboratoryP.O. Box 1625Idaho Falls, ID 83415-2050e-mail: kmm4inel.govAbstractRapid Solidification Process (RSP) Tooling is a spray forming technology tailored forproducing molds and dies. The approach combines rapid solidification processing and net-shapematerials processing in a single step. The ability of the sprayed deposit to capture features of thetool pattern eliminates costly machining operations in conventional mold making and reducesturnaround time. Moreover, rapid solidification suppresses carbide precipitation and growth,allowing many ferritic tool steels to be artificially aged, an alternative to conventional heattreatment that offers unique benefits. Material properties and microstructure transformationduring heat treatment of spray-formed H13 tool steel are described.IntroductionMolds, dies, and related tooling are used to shape many of the plastic and metal components weuse every day at home or at work. The process involves machining the negative of a desired partshape (core and cavity) from a forged tool steel or a rough metal casting, adding coolingchannels, vents, and other mechanical features, followed by grinding. Many molds and diesundergo 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 arethe workhorse of industry for long production runs. Machining tool steels is capitalequipment intensive because specialized equipment is often needed for individual machiningsteps. Tooling must be machined accurately. Oftentimes many individual components must fittogether correctly for the final product to function properly.2Costs for plastic injection molds vary with size and complexity, ranging from about $10,000 toover $300,000 (U.S.), and have lead times of 3 to 6 months. Tool checking and part qualificationmay require an additional 3 months. Large die-casting dies for transmissions and sheet metalstamping dies for making automobile body panels may cost more than $1million (U.S.). Leadtimes 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 carsand trucks.Spray forming offers great potential for reducing the cost and lead time for tooling byeliminating many of the machining, grinding, and polishing unit operations. In addition, sprayforming provides a powerful means to control segregation of alloying elements duringsolidification and carbide formation, and the ability to create beneficial metastable phases inmany popular ferritic tool steels. As a result, relatively low temperature precipitation hardeningheat treatment can be used to tailor properties such as hardness, toughness, thermal fatigueresistance, and strength. This paper describes the application of spray forming technology forproducing H13 tooling for injection molding and die casting applications, and the benefits of lowtemperature heat treatment.RSP ToolingRapid Solidification Process (RSP) Tooling, is a spray forming technology tailored forproducing 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 molddesign 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, typicallyalumina 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. Theresultant 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 holdingblock 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 andproduction runs in plastic injection molding and die casting.Figure 1. RSP Tooling processing steps.3An important benefit of RSP Tooling is that it allows molds and dies to be made early in thedesign cycle for a component. True prototype parts can be manufactured to assess form, fit, andfunction using the same process planned for production. If the part is qualified, the tooling can berun in production as conventional tooling would. Use of a digital database and RP technologyallows design modifications to be easily made.Experimental ProcedureAn 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 weredemolded, fired in a kiln, and cooled to room temperature. H13 tool steel was induction meltedunder a nitrogen atmosphere, superheated about 100C, and pressure-fed into a bench-scaleconverging/diverging spray nozzle, designed and constructed in-house. An inert gas atmospherewithin the spray apparatus minimized in-flight oxidation of the atomized droplets as theydeposited onto the tool pattern at a rate of about 200 kg/h. Gas-to-metal mass flow ratio wasapproximately 0.5.For tensile property and hardness evaluation, the spray-formed material was sectioned using awire EDM and surface ground to remove a 0.05 mm thick heat-affected zone. Samples wereheat treated in a furnace that was purged with nitrogen. Each sample was coated with BN andplaced 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, andair cooled. Conventionally heat treated H13 was austenitized at 1010C for 30 min., airquenched, and double tempered (2 hr plus 2 hr) at 538C.Microhardness was measured at room temperature using a Shimadzu Type M Vickers HardnessTester by averaging ten microindentation readings. Microstructure of the etched (3% nital) toolsteel was evaluated optically using an Olympus Model PME-3 metallograph and an AmrayModel 1830 scanning electron microscope. Phase composition was analyzed via energy-dispersive spectroscopy (EDS). The size distribution of overspray powder was analyzed using aMicrotrac Full Range Particle Analyzer after powder samples were sieved at 200 m to removecoarse flakes. Sample density was evaluated by water displacement using Archimedes principleand a Mettler balance (Model AE100).A quasi 1-D computer code developed at INEEL was used to evaluate multiphase flow behaviorinside 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 thedroplet phase in a Lagrangian manner with full aerodynamic and energetic coupling between thedroplets and transport gas. The liquid metal injection system is coupled to the throat gasdynamics, and effects of heat transfer and wall friction are included. The code also includes anonequilibrium solidification model that permits droplet undercooling and recalescence. Thecode was used to map out the temperature and velocity profile of the gas and atomized dropletswithin the nozzle and free jet regions.4Results and DiscussionSpray forming is a robust rapid tooling technology that allows tool steel molds and dies to beproduced in a straightforward manner. Examples of die inserts are given in Figure 2. Each wasspray 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 toolsteel insert.Particle and Gas BehaviorParticle mass frequency and cumulative mass distribution plots for H13 tool steel sprays aregiven in Figure 3. The mass median diameter was determined to be 56 m by interpolation ofsize corresponding to 50% cumulative mass. The area mean diameter and volume meandiameter were calculated to be 53 m and 139 m, respectively. Geometric standard deviation,d=(d84/d16) , is 1.8, where d84 and d16 are particle diameters corresponding to 84% and 16%cumulative mass in Figure 3.5Figure 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 H13tool steel solid fraction (Figure 4b), inside the nozzle and free jet regions. Gas velocity increasesuntil 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 thevelocity field, accelerating inside the nozzle and decelerating outside. After reaching theirterminal velocity, larger droplets (150 m) are less perturbed by the flow field due to theirgreater momentum.It is well known that high particle cooling rates in the spray jet (103-106 K/s) and bulk deposit (1-100 K/min) are present during spray forming 7. Most of the particles in the spray haveundergone recalescence, resulting in a solid fraction of about 0.75. Calculated solid fractionprofiles of small (30 m) and large (150 m) droplets with distance from the nozzle inlet, areshown in Figure 4b.Spray-Formed DepositsThis high heat extraction rate reduces erosion effects at the surface of the tool pattern. Thisallows relatively soft, castable ceramic pattern materials to be used that would not be satisfactorycandidates for conventional metal casting processes. With suitable processing conditions, fine6Figure 4. Calculated particle and gas behavior in nozzle and free jet regions. (a) Velocity profile.(b) Solid fraction.7surface detail can be successfully transferred from the pattern to spray-formed mold. Surfaceroughness at the molding surface is pattern dependent. Slurry-cast commercial ceramics yield asurface roughness of about 1 m Ra, suitable for many molding applications. Deposition of toolsteel onto glass plates has yielded a specular surface finish of about 0.076 m Ra. At the currentstate of development, dimensional repeatability of spray-formed molds, starting with a commonmaster, is about 0.2%.ChemistryThe 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 diecasting. It is the most popular die casting alloy worldwide and second most popular tool steel forplastic 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 andvanadium additions (about 1%) that form stable carbides to increase resistance to erosive wear8. 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 steelElementCMnCrMoVSiFeStock H130.410.395.151.410.91.06Bal.Spray Formed H130.410.385.101.420.91.08Bal.MicrostructureThe size, shape, type, and distribution of carbides found in H13 tool steel is dictated by theprocessing method and heat treatment. Normally the commercial steel is machined in the millannealed condition and heat treated (austenitized/quenched/tempered) prior to use. It is typicallyaustenitized at about 1010C, quenched in air or oil, and carefully tempered two or three times at540 to 650C to obtain the required combination of hardness, thermal fatigue resistance, andtoughness.Commercial, forged, ferritic tool steels cannot be precipitation hardened because after electroslagremelting 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 andto be more uniformly distributed in the matrix 9-11. Properties can be tailored by artificialaging or conventional heat treatment.A benefit of artificial aging is that it bypasses the specific volume changes that occur duringconventional heat treatment that can lead to tool distortion. These specific volume changes occuras the matrix phase transforms from ferrite to austenite to tempered martensite and must beaccounted 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, areoftentimes not included as the material has a tendency to slump during austenitization or distort8during quenching. Tool distortion is not observed during artificial aging of spray-formed toolsteels because there is no phase transformation.An optical photomicrograph of spray-formed H13 is shown in Figure 5 together with an SEMimage, in backscattered electron (BSE) mode. Energy dispersive spectroscopic (EDS)composition analysis of some features in the photomicrographs is also given. While exactquantitative data is not possible due to sampling volume limitations, results suggest that grainboundaries are particularly rich in V. Intragranular (matrix) regions are homogeneous and richin Fe. X-ray diffraction analysis indicates that the matrix phase is primarily ferrite (bainite) withvery little retained austenite, and that the alloying elements are largely in solution. Discreteintragranular carbides are relatively rare, very small (about 0.1 m) and predominatelyvanadium-rich MC carbides. M2C carbides are not observed.ElementSiVCrMnMoFeSpot #1 (wt%)0.6132.136.680.172.0558.36Spot #2 (wt%)1.590.795.350.282.2889.72Figure 5. Photomicrographs of as-deposited H13 tool steel. 3% nital etch. (a) Opticalphotomicrograph. (b) SEM image (BSE mode) near a grain boundary. Table gives EDScomposition of numbered features.9Figure 6 illustrates the microstructure of spray-formed H13 aged at 500C for 1 hr. Duringaging, 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 mdiameter) vanadium-rich MC carbide precipitates. The precipitates are uniformly distributedthroughout 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 formationof M7C3 and M6C carbides, and a decrease in hardness. The photomicrographs of Figure 7illustrate the dramatic change in carbide size. BSE imaging clearly differentiates Mo/Cr-richcarbides from V-rich carbides, shown as light and dark areas, respectively, in Figure 7. EDSanalysis of these carbides is also given in Figure 7.ElementSiVCrMnMoFeSpot #1 (wt%)0.0613.807.202.642.4473.86Spot #2 (wt%)1.520.825.480.232.3889.57Figure 6. Photomicrographs of spray-formed/aged H13 tool steel. 500C soak for 1 hr. 3% nitaletch. (a) Optical photomicrograph. (b) SEM image (BSE mode) near a grain boundary. Tablegives EDS composition of numbered features.10ElementSiVCrMnMoFeSpot #1 (wt%)082.279.0104.334.39Spot #2 (wt%)05.3025.70055.5513.45Spot #3 (wt%)1.600.886.320.282.9288.00Figure 7. SEM Photomicrograph (BSE mode) of spray-formed/aged H13 tool steel showingadjacent 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 PropertiesPorosity in spray-formed metals depends on processing conditions. The average as-depositeddensity of spray-formed H13 was 98-99% of theoretical, as measured by water displacementusing Archimedes principle.As-deposited hardness was typically about 59 HRC, harder than commercial forged and heattreated material (28 to 53 HRC depending on tempering temperature), and significantly harderthan annealed H13 (200 HB). The high hardness is attributable to lattice strain due to quenchingstresses 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, aircooled, 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 roseto a peak hardness of approximately 62 HRC at 500C. Higher soak temperature resulted in adrop in hardness as carbide particles coarsened.Peak age hardness in spray-formed H13 tool steel is notably higher than that of commercialhardened material. Normally, commercial H13 dies used in die casting are tempered to about 40to 45 HRC as a tradeoff since high hardness dies, while desirable for wear resistance, are proneto premature failure via thermal fatigue as the dies surface is rapidly cycled from 300C to700C during aluminum production runs.11Figure 8. Hardness of artificially aged spray-formed H13 tool steel following one hour soaks attemperature. Hardness range of conventionally heat treated H13 included for comparison.As-deposited spray-formed material was also hardened following the conventional heat treatmentcycle 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 plus2 hr) at (538C). The microstructure in both cases was found to be tempered martensite with afew spheroidal particles of alloy carbide. Hardness values for both materials were very nearlyidentical.Table 2 gives the ultimate tensile strength and yield strength of spray-formed, cast, andforged/heat treated H13 tool steel measured at test temperatures of 22 and 550C. Values forspray formed H13 are given in the as-deposited condition and following artificial aging andconventional heat treatments. Values for the spray-formed material are comparable to those offorged and are considerably higher than those of cast tool steel. The spray-formed material seemsto retain its strength somewhat better than forged/heat treated H13 at higher temperatures.12Table 2. H13 tool steel mechanical properties.Sample/Heat TreatmentUltimateTensile Strength(MPa)YieldStrength(MPa)TestTemperature(C)Spray formed/as-deposited106195122Spray formed /aged at 540C1964188122Spray formed /aged at 540C16471475550Spray formed /conventional heat treatment*1358115822Cast60022Cast/conventional heat treatment*88222Commercial forged/ heat treated*1799168122Commercial forged/ heat treated*13231247550* austenitized at 1010C, double tempered (2hr+ 2hr) at 590C. no yield at 0.2% offset.Summary Spray forming is a r