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1、<p> Heat Treatment of Die and Mould Oriented Concurrent Design</p><p> Abstract: </p><p> Many disadvantages exist in the traditional die design method which belongs to serial pattern.
2、It is well known that heat treatment is highly important to the dies. A new idea of concurrent design for heat treatment process of die and mould was developed in order to overcome the existent shortcomings of heat treat
3、ment process. Heat treatment CAD/CAE was integrated with concurrent circumstance and the relevant model was built. These investigations can remarkably improve efficiency, reduce cost an</p><p> Key words:di
4、e design; heat treatment; mould</p><p> Traditional die and mould design,mainly by experience or semi—experience,is isolated from manufacturing process.Before the design is finalized,the scheme of die and m
5、ould is usually modified time and again,thus some disadvantages come into being,such as long development period,high cost and uncertain practical effect.Due to strong desires for precision,service life,development period
6、 and cost,modern die and mould should be designed and manufactured perfectly.Therefore more and more advanced tech</p><p> Heat treatment of die and mould is as important as design,manufacture and assembly
7、because it has a vital effect on manufacture,assembly and service life.Design and manufacture of die and mould have progressed rapidly,but heat treatment lagged seriously behind them.As die and mould industry develops,he
8、at treatment must ensure die and mould there are good state of manufacture,assembly and wear—resistant properties by request. Impertinent heat treatment can influence die and mould manufacturing su</p><p>
9、Concurrent engineering takes computer integration system as a carrier,at the very start subsequent each stage and factors have been considered such as manufacturing,heat treating,properties and so forth in order to avoid
10、 the error.The concurrent pattern has dismissed the defect of serial pattern,which bring about a revolution against serial pattern.</p><p> In the present work.the heat treatment was integrated into the con
11、current circumstance of the die and mould development,and the systemic and profound research was performed.</p><p> 1 Heat Treatment Under Concurrent Circumstance</p><p> The concurrent patte
12、rn differs ultimately from the serial pattern(see Fig.1).With regard to serial pattern,the designers mostly consider the structure and function of die and mould,yet hardly consider the consequent process,so that the form
13、er mistakes are easily spread backwards.Meanwhile,the design department rarely communicates with the assembling,cost accounting and sales departments.These problems certainly will influence the development progress of di
14、e and mould and the market foreground.Wh</p><p> Heat treatment process in the concurrent circumstance is made out not after blueprint and workpiece taken but during die and mould designing.In this way,it i
15、s favorable to optimizing the heat treatment process and making full use of the potential of the materials.</p><p> 2 Integration of Heat Treatment CAD/CAE for Die and Mould</p><p> It can be
16、 seen from Fig.2 that the process design and simulation of heat treatment are the core of integration frame.After information input via product design module and heat treatment process generated via heat treatment CAD an
17、d heat treatment CAE module will automatically divide the mesh for parts drawing,simulation temperature field microstructure analysis after heat—treatment and the defect of possible emerging (such as overheat,over burnin
18、g),and then the heat treatment process is judged if</p><p> The concurrent engineering based integration frame can share information with other branch.That makes for optimizing the heat treatment process an
19、d ensuring the process sound.</p><p> 2.1 3-D model and stereoscopic vision technology for heat treatment</p><p> The problems about materials,structure and size for die and mould can be disco
20、vered as soon as possible by 3-D model for heat treatment based on the shape of die and mould.Modeling heating condition and phase transformation condition for die and mould during heat treatment are workable,because it
21、has been broken through for the calculation of phase transformation thermodynamics,phase transformation kinetics,phase stress,thermal stress,heat transfer,hydrokinetics etc.For example,3-D heat—conducti</p><p&
22、gt; 2.2 Heat treatment process design</p><p> Due to the special requests for strength,hardness,surface roughness and distortion during heat treatment for die and mould,the parameters including quenching m
23、edium type,quenching temperature and tempering temperature and time,must be properly selected,and whether using surface quenching or chemical heat treatment the parameters must be rightly determined.It is difficult to de
24、termine the parameters by computer fully.Since computer technology develops quickly in recent decades,the difficulty with</p><p> 2.3 Data base for heat treatment</p><p> A heat treatment data
25、base is described in Fig.3.The database is the foundation of making out heat treatment process.Generally,heat treatment database is divided into materials database and process database.It is an inexorable trend to predic
26、t the property by materials and process.Although it is difficult to establish a property database,it is necessary to establish the database by a series of tests.The materials database includes steel grades,chemical compo
27、sitions,properties and home and abroad </p><p> 2.4 Tool and equipment for heat treatment</p><p> After heat treatment process is determined,tool and equipment CAD/CAE system transfers the inf
28、ormation about design and manufacture to the numerical control device.Through rapid tooling prototype,the reliability of tool and the clamping apparatus can be judged.The whole procedure is transferred by network,in whic
29、h there is no man—made interference.</p><p> 3 Key Technique</p><p> 3.1 Coupling of temperature,microstructure,stress and property</p><p> Heat treatment procedure is a procedur
30、e of temperature-microstructure—stress interaction.The three factors can all influence the property (see Fig.4).During heating and cooling,hot stress and transformation will come into being when microstructure changes.Tr
31、ansformation temperature-microstructure and temperature—microstructure—and stress-property interact on each other.Research on the interaction of the four factors has been greatly developed,but the universal mathematic mo
32、del has not been built</p><p> Even so,comparing experience method with qualitative analysis,heat treatment simulation by computer makes great progress.</p><p> 3.2 Establishment and integrati
33、on of models</p><p> The development procedure for die and mould involves design,manufacture,heat treatment,assembly,maintenance and so on.They should have own database and mode1.They are in series with eac
34、h other by the entity—relation model.Through establishing and employing dynamic inference mechanism ,the aim of optimizing design can be achieved.The relation between product model and other models was built.The product
35、model will change in case the cell model changes.In fact,it belongs to the relation of data wit</p><p> All design cells are connected by communication network.</p><p> 3.3 Management and harm
36、ony among members</p><p> The complexity of die and mould requires closely cooperating among item groups.Because each member is short of global consideration for die and mould development,they need to be ma
37、naged and harmonized.Firstly,each item group should define its own control condition and resource requested,and learn of the request of up-and-down working procedure in order to avoid conflict.Secondly,development plan s
38、hould be made out and monitor mechanism should be established.The obstruction can be duly excluded i</p><p> Agile management and harmony redound to communicating information, increasing efficiency,and redu
39、cing redundancy.Meanwhile it is beneficial for exciting creativity,clearing conflict and making the best of resource.</p><p> 4 Conclusions</p><p> (1) Heat treatment CAD/CAE has been integrat
40、ed into concurrent design for die and mould and heat treatment is graphed,which can increase efficiency,easily discover problems and clear conflicts.</p><p> (2) Die and mould development is performed on th
41、e same platform.When the heat treatment process is made out,designers can obtain correlative information and transfer self-information to other design departments on the platform.</p><p> (3) Making out cor
42、rect development schedule and adjusting it in time can enormously shorten the development period and reduce cost.</p><p> References:</p><p> [1] ZHOU Xiong-hui,PENG Ying-hong.The Theory and T
43、echnique of Modern Die and Mould Design and Manufacture[M].Shanghai:Shanghai Jiaotong University Press 2000(in Chinese).</p><p> [2] Kang M,Park& Computer Integrated Mold Manufacturing[J].Int J Computer
44、 Integrated Manufacturing,1995,5:229-239.</p><p> [3] Yau H T,Meno C H.Concurrent Process Planning for Finishing Milling and Dimensional Inspection of Sculptured Surface in Die and Mould Manufacturing[J].In
45、t J Product Research,1993,31(11):2709—2725.</p><p> [4] LI Xiang,ZHOU Xiong-hui,RUAN Xue-yu.Application of Injection Mold Collaborative Manufacturing System [J].JournaI of Shanghai Jiaotong University,2000,
46、35(4):1391-1394.</p><p> [5] Kuzman K,Nardin B,Kovae M ,et a1.The Integration of Rapid Prototyping and CAE in Mould Manufacturing [J].J Materials Processing Technology,2001,111:279—285.</p><p>
47、 [6] LI Xiong,ZHANG Hong—bing,RUAN Xue-yu,et a1.Heat Treatment Process Design Oriented Based on Concurrent Engineering[J].Journal of Iron and Steel Research,2002,14(4):26—29.</p><p><b> 文獻(xiàn)出處:</b&g
48、t;</p><p> LI Xiong,ZHANG Hong-bing,RUAN Xue—yu,LUO Zhong—hua,ZHANG Yan. Heat Treatment of Die and Mould Oriented Concurrent Design[J]. Journal of Iron and Steel Research,2006,13(1):40-43,74</p><
49、p> 模具熱處理及其導(dǎo)向平行設(shè)計(jì)</p><p><b> 摘要:</b></p><p> 在一系列方式中,傳統(tǒng)模具設(shè)計(jì)方法存在許多缺點(diǎn)。眾所周知,熱處理對(duì)模具起著非常重要的作用。為了克服模具熱處理工藝存在的缺點(diǎn),一種新的模具熱處理工藝并行設(shè)計(jì)方法已經(jīng)被開(kāi)發(fā)出來(lái)了。熱處理CAD/CAE技術(shù)是集成了并行環(huán)境和有關(guān)模型而建立的。這些調(diào)查研究可以顯著提高效率,
50、降低成本,并保證產(chǎn)品質(zhì)量達(dá)到R和D級(jí)。</p><p> 關(guān)鍵詞:模具設(shè)計(jì);熱處理;模具</p><p> 傳統(tǒng)模具設(shè)計(jì)主要是依照自身實(shí)踐經(jīng)驗(yàn)或依照部分實(shí)踐經(jīng)驗(yàn),而不是制造工藝。在設(shè)計(jì)完成之前,模具方案通常要被一次又一次的改進(jìn),于是有些缺點(diǎn)便出現(xiàn),例如開(kāi)發(fā)時(shí)期長(zhǎng),成本高和實(shí)際效果不明顯。由于對(duì)精確性、使用壽命、開(kāi)發(fā)期和費(fèi)用的嚴(yán)格要求,先進(jìn)的模具要求設(shè)計(jì)和制造得十分完善。因此越來(lái)越先進(jìn)的
51、技術(shù)和創(chuàng)新方法被應(yīng)用其中,例如并行工程、敏捷制造業(yè)、虛擬制造業(yè)、協(xié)同合作設(shè)計(jì)等。</p><p> 模具的熱處理與模具設(shè)計(jì),制造和裝配同樣重要。因?yàn)樗鼘?duì)模具的制造裝配和使用壽命又及其重要的影響。模具設(shè)計(jì)與制造發(fā)展十分迅速,但是熱處理發(fā)展卻嚴(yán)重滯后它們。隨著模具工業(yè)的發(fā)展,熱處理必須保證模具有良好的制造裝配和磨損耐熱性能。不切實(shí)際的熱處理將導(dǎo)致模具材料過(guò)硬或過(guò)軟,同時(shí)影響模具裝配性能。傳統(tǒng)的熱處理工藝是按照設(shè)計(jì)師
52、提出的方法和特性制作出來(lái)的。這樣會(huì)使模具設(shè)計(jì)師和熱處理工藝師意見(jiàn)產(chǎn)生分歧,而模具設(shè)計(jì)師卻不能充分地了解熱處理工藝和材料的性能,相反熱處理工藝師卻很少了解模具的使用環(huán)境和設(shè)計(jì)思路。這些分歧將在很大程度上影響模具的發(fā)展。因此,如果把熱處理工藝設(shè)計(jì)放在設(shè)計(jì)階段之前,則縮短開(kāi)發(fā)周期,減少花費(fèi)和保證質(zhì)量等目標(biāo)將會(huì)被考慮,而且從串行到并行的發(fā)展模式也將會(huì)實(shí)現(xiàn)。</p><p> 并行工程是以計(jì)算機(jī)集成系統(tǒng)作為載體,在開(kāi)始以
53、后,每個(gè)階段和因素都被看作如制造、熱處理、性能等等,以避免出現(xiàn)錯(cuò)誤。并行模式已經(jīng)摒除了串行模式的缺陷,由此帶來(lái)了一場(chǎng)對(duì)串行模式的革命。</p><p> 在當(dāng)前的工作中,熱處理被集成到了模具開(kāi)發(fā)的并行環(huán)境中,同時(shí)也正在進(jìn)行這種系統(tǒng)性和深入性的研究。</p><p> 1.熱處理下的并行環(huán)境</p><p> 并行模式與串行模式存在根本的不同(見(jiàn)圖1)。對(duì)于串行
54、模式,設(shè)計(jì)者大多考慮的是模具的結(jié)構(gòu)與功能,但很難考慮相關(guān)的工藝,以致前者的錯(cuò)誤很容易蔓延到后面。與此同時(shí),設(shè)計(jì)本門(mén)很少與裝配,預(yù)算會(huì)計(jì)和銷(xiāo)售部門(mén)溝通。這些問(wèn)題當(dāng)然會(huì)影響模具的開(kāi)發(fā)進(jìn)度和市場(chǎng)前景。然而在并行模式中,不但以上部門(mén)關(guān)系聯(lián)系密切,所有參加模具開(kāi)發(fā)的部門(mén)都與買(mǎi)家有密切的交流。這有助于協(xié)調(diào)各部門(mén)消除矛盾,提高工作效率,同時(shí)降低成本。</p><p><b> (a)</b></p
55、><p><b> (b)</b></p><p> (a)串行模式 (b)并行模式</p><p> 圖1.基于摸具開(kāi)發(fā)的串行工程與并行工程系統(tǒng)框架示意圖</p><p> 并行環(huán)境下的熱處理工藝不是在方案和工件確定以后,而是在模具設(shè)計(jì)的時(shí)候制定出來(lái)的。這樣的話(huà),將有利于優(yōu)化熱處理工藝,充分利用
56、材料。</p><p> 2.模具熱處理CAD/CAE一體化</p><p> 從圖2中可以看出,熱處理工藝的設(shè)計(jì)與模擬是一體化模式的核心。在信息輸入產(chǎn)品模塊中后,經(jīng)熱處理工藝過(guò)程產(chǎn)生的熱處理CAD和熱處理CAE模塊將對(duì)于零件圖,熱處理以后模擬溫度場(chǎng)的微觀結(jié)構(gòu)分析和可能出現(xiàn)的缺陷(例如過(guò)熱,燒傷)自動(dòng)劃分網(wǎng)絡(luò),如果優(yōu)化是根據(jù)立體視覺(jué)技術(shù)的結(jié)果重新出現(xiàn),則這項(xiàng)熱處理工藝已經(jīng)被審核。而且工
57、具與夾具的CAD和CAE也集成于這種系統(tǒng)中</p><p><b> 。</b></p><p> 圖2.并行工程熱處理CAD/CAE一體化系統(tǒng)框架示意圖</p><p> 以并行工程為基礎(chǔ)的集成模式可以與其它類(lèi)似模式共享信息。這樣使熱處理工藝得到優(yōu)化,并確保改工藝準(zhǔn)確。</p><p> 2.1采用三維模型和立
58、體視覺(jué)技術(shù)的熱處理</p><p> 在形成模具的基礎(chǔ)上,材料,結(jié)構(gòu)和尺寸的問(wèn)題能通過(guò)熱處理三維模型盡快發(fā)現(xiàn)出來(lái)。在熱處理過(guò)程中,模具加熱條件和相變條件是切合實(shí)際的,因?yàn)橥ㄟ^(guò)計(jì)算相變熱力、相變動(dòng)力、相應(yīng)力、熱應(yīng)力、傳熱速度、流體動(dòng)力等已經(jīng)取得重要突破。例如,能進(jìn)行局部復(fù)雜表面和不對(duì)稱(chēng)模具的三維熱傳導(dǎo)模型計(jì)算,和能進(jìn)行微觀結(jié)構(gòu)轉(zhuǎn)變的MARC軟件模型。計(jì)算機(jī)能夠在任何時(shí)間提交溫度,微觀結(jié)構(gòu)和應(yīng)力的信息,并通過(guò)連接溫
59、度場(chǎng)微觀結(jié)構(gòu)領(lǐng)域和力場(chǎng)來(lái)顯示三維形式的全部改變過(guò)程。如果再加上這種特性,則各部分性能都能通過(guò)計(jì)算機(jī)預(yù)見(jiàn)。</p><p> 2.2熱處理工藝設(shè)計(jì)</p><p> 由于對(duì)強(qiáng)度和硬度,表面粗糙度和模具熱處理變形的特殊要求,淬火介質(zhì)的種類(lèi)、淬火溫度、回火溫度和時(shí)間等參數(shù)特性必須經(jīng)過(guò)適當(dāng)?shù)倪x擇,以及是否使用表面淬火或化學(xué)熱處理,這種特性必須準(zhǔn)確的制定下來(lái)。自從計(jì)算機(jī)技術(shù)在最近幾十年迅速的發(fā)展
60、,難以進(jìn)行大型計(jì)算已經(jīng)成為過(guò)去。通過(guò)模擬和仔細(xì)考慮熱處理特性,熱處理后的成本和所須時(shí)間,這些都并不難優(yōu)化熱處理工藝。</p><p><b> 2.3熱處理數(shù)據(jù)庫(kù)</b></p><p> 熱處理數(shù)據(jù)庫(kù)在圖3中描述。數(shù)據(jù)庫(kù)是制定熱處理工藝的基礎(chǔ)。一般來(lái)說(shuō),熱處理數(shù)據(jù)庫(kù)分為材料數(shù)據(jù)庫(kù)和工藝數(shù)據(jù)庫(kù)。通過(guò)材料和工藝來(lái)預(yù)測(cè)特性已成為一種必然的趨勢(shì)。盡管很難建立一個(gè)特性數(shù)據(jù)
61、庫(kù),但通過(guò)一系列的測(cè)試來(lái)建立數(shù)據(jù)庫(kù)是必要的。材料數(shù)據(jù)庫(kù)包括材料牌號(hào)、化學(xué)成分、性能和國(guó)內(nèi)外同級(jí)別目錄表。工藝數(shù)據(jù)庫(kù)包括熱處理標(biāo)準(zhǔn)、種類(lèi)、保溫時(shí)間和冷卻溫度?;跀?shù)據(jù)庫(kù),熱處理工藝可以通過(guò)推理規(guī)則創(chuàng)造出來(lái)</p><p><b> 。</b></p><p><b> 圖3.熱處理數(shù)據(jù)庫(kù)</b></p><p> 2.
62、4熱處理工具和設(shè)備</p><p> 在熱處理工藝確定以后,工具及設(shè)備CAD/CAE系統(tǒng)傳送設(shè)計(jì)和制造的數(shù)值信息來(lái)控制裝置。通過(guò)快速模具成型,可靠的工具和夾具都能被確定。整個(gè)程序通過(guò)網(wǎng)絡(luò)傳送,不存在任何人為干擾。</p><p><b> 3.關(guān)鍵技術(shù)</b></p><p> 3.1溫度,微觀結(jié)構(gòu),應(yīng)力和特性的聯(lián)系</p>
63、<p> 熱處理程序是一個(gè)溫度,微觀結(jié)構(gòu)和應(yīng)力互相作用的程序。三方面都能影響材料特性(見(jiàn)圖4)。在加熱和冷卻期間,當(dāng)微觀結(jié)構(gòu)轉(zhuǎn)變時(shí)熱應(yīng)力和相變遲早會(huì)出現(xiàn)。微觀結(jié)構(gòu)溫度相變和溫度-微觀結(jié)構(gòu)-應(yīng)力特性相互影響。對(duì)相互作用的四個(gè)因素的調(diào)查已經(jīng)取得很大的發(fā)展,但普通的數(shù)學(xué)模型還沒(méi)有建立。許多模型能很好的滿(mǎn)足測(cè)試結(jié)果,但不能投入到實(shí)踐當(dāng)中。大部分模型的難點(diǎn)是用分析的方法處理的,同時(shí)數(shù)值方法也運(yùn)用了,導(dǎo)致存在不準(zhǔn)確的計(jì)算</p&
64、gt;<p><b> 。</b></p><p> 圖4.熱處理工藝圖解</p><p> 即使如此,把經(jīng)驗(yàn)方法與定性分析相比較,通過(guò)計(jì)算機(jī)來(lái)進(jìn)行熱處理模擬取得了很大的進(jìn)展。</p><p> 3.2模型的建立和融合</p><p> 在模具的開(kāi)發(fā)過(guò)程中,涉及到設(shè)計(jì)、制造、熱處理、裝配、維修等。
65、它們應(yīng)該有自己的數(shù)據(jù)庫(kù)和模型。它們通過(guò)事物的內(nèi)在聯(lián)系建立模型,互相串聯(lián)起來(lái),盡管建立和運(yùn)用動(dòng)態(tài)推理機(jī)制,但其目的在于完成優(yōu)化設(shè)計(jì)。產(chǎn)品模型和其它模型的聯(lián)系已被建立。如果細(xì)小組織模型發(fā)生改變,則產(chǎn)品模型也將改變。事實(shí)上,它屬于數(shù)據(jù)庫(kù)與模具之間的聯(lián)系。當(dāng)熱處理模型集成到系統(tǒng)以后,它已不再是一個(gè)孤立的單位,而是一個(gè)部分,同時(shí)在系統(tǒng)中接近其它模型。在搜查后,熱處理數(shù)據(jù)庫(kù)的計(jì)算和推理能力,熱處理程序都被幾何模型,模具制造模型和預(yù)算所限制,這是通行
66、的。如果這種限制不服從,系統(tǒng)會(huì)發(fā)出解釋性的警告。</p><p> 所用設(shè)計(jì)的細(xì)小組織都是通過(guò)互連網(wǎng)連接的。</p><p> 3.3各部分之間的管理和協(xié)調(diào)</p><p> 復(fù)雜的模具需要其中各項(xiàng)目組之間密切合作。因?yàn)榭紤]到模具的開(kāi)發(fā),各部分都存在缺點(diǎn),它必須得到管理和協(xié)調(diào)。首先,各項(xiàng)目組應(yīng)該確定其本身的控制條件和資源要求,同時(shí)了解不同環(huán)境下的工作程序,以避
67、免發(fā)生沖突。其次,要提出開(kāi)發(fā)計(jì)劃和建立監(jiān)控機(jī)制。如果開(kāi)發(fā)受到限制則可逐步排除。</p><p> 敏捷管理和協(xié)調(diào)有助于交流信息,提高效率和減少材料。同時(shí)這有利于激發(fā)人的創(chuàng)造力,消除阻礙和制定出最好的方法。</p><p><b> 4.總結(jié)</b></p><p> ?、艧崽幚鞢AD/CAE技術(shù)已被集成到模具并行設(shè)計(jì)中去,同時(shí)熱處理已被制成
68、圖表,這有利于提高效率,較易發(fā)現(xiàn)問(wèn)題并解決問(wèn)題。</p><p> ?、颇P偷拈_(kāi)發(fā)已在同一個(gè)平臺(tái)運(yùn)行。在這個(gè)平臺(tái)中,當(dāng)熱處理工藝制定出來(lái)后,設(shè)計(jì)人員可獲得相關(guān)信息和轉(zhuǎn)讓部分信息到其它設(shè)計(jì)部門(mén)。</p><p> ?、侵贫ǔ稣_的開(kāi)發(fā)計(jì)劃并按時(shí)調(diào)整可以極大縮短開(kāi)發(fā)周期和降低成本。</p><p><b> 文獻(xiàn)出處:</b></p>
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