0141-軸架沖壓工藝及沖孔彎曲落料級進模具的設計【全套13張CAD圖】
0141-軸架沖壓工藝及沖孔彎曲落料級進模具的設計【全套13張CAD圖】,全套13張CAD圖,沖壓,工藝,沖孔,彎曲,曲折,落料級進,模具,設計,全套,13,cad
畢業(yè)設計(論文)開題報告
題目 軸架沖壓工藝及模具的設計
一、選題的依據(jù)及意義:
(1)通過計算和繪圖,學會運用標準、規(guī)范、手冊、圖冊和查閱有關技術資料等,培養(yǎng)模具設計的基本技能
(2)綜合運用冷沖模課程和其它有關先修課程的理論及生產(chǎn)實踐的知識去分析和解決模具設計問題,并使所學專業(yè)知識得到進一步鞏固和深化。
(3)學習模具設計的一般方法,了解和掌握常用模具整體設計、零部件的設計過程和計算方法,培養(yǎng)正確的設計思想和分析問題、解決問題的能力,特別是總體設計和計算的能力。
二、國內(nèi)外研究概況及發(fā)展趨勢(含文獻綜述):
隨著我國成為世界制造業(yè)的中心,電子信息技術中的電子元器件和汽車部件越來越多的成為中國制造,而模具是機械、電子、汽車、家電等工業(yè)產(chǎn)品的基礎工藝裝備,作為工業(yè)基礎,模具的質量、精度、壽命對其它工業(yè)的發(fā)展起著十分重要的作用,在國際上稱為“工業(yè)之母”。 2005年我國模具產(chǎn)值為610億人民幣,2006年約720億,平均每年以20%~25%的速度增長。模具的技術水平明顯有了提高,一些國產(chǎn)優(yōu)質模具的性能已接近國外同類產(chǎn)品的先進水平,但由于我國起步晚,許多模具不得不依賴進口,與發(fā)達國家相比差距還非常大。
隨著科學技術的不斷進步和工業(yè)生產(chǎn)的迅速發(fā)展,許多新技術、新工藝、新設備、新材料不斷涌現(xiàn),因而促進了沖壓技術的不斷革新和發(fā)展。其主要發(fā)展如下:
1. 工藝分析計算的現(xiàn)代化。它將與現(xiàn)代數(shù)學、計算機技術聯(lián)姻,對加工零件進行計算機模擬和有限元分析,達到預測某一工藝方案對零件成形的可能性與成形過程中可能會發(fā)生的問題,供設計人員修改和選擇。
2 .模具計算輔助設計、制造與分析(CAD/CAM/CAE)的研究和應用將極大地提高模具制造效率,提高模具質量,使模具設計與制造技術實現(xiàn)一體化。
3. 模具的標準化、商品化、機械化及專業(yè)化自動生產(chǎn)
三、研究內(nèi)容及實驗方案:
1,給定某軸架零件圖(如右圖),其研究內(nèi)容:
1)分析該軸架的沖壓工藝性,并提出幾種行的沖壓工藝方案;
2)在工藝方案分析的基礎上,優(yōu)選沖壓工藝路線;
3)按選定的工藝路線進行工藝計算;
4)確定模具結構(模架型式、導向方式、毛坯定位、卸料、推料、壓料、出件方式等)。
5)確定模具主要零部件結構與尺寸;
6)設計模具的裝配圖和零件工作圖;
7)撰寫畢業(yè)設計說明書。
2,初步確定方案:
方案一:先沖孔,再彎曲,后落料。單工序模生產(chǎn)。
方案二:沖孔—彎曲—落料級進沖壓。級進模生產(chǎn)。
方案三:落料-拉深-沖孔復合模沖壓。復合模生產(chǎn)。
表2-1 各類模具結構及特點比較
模具種類比較項目
單工序模
(無導向)(有導向)
級進模
復合模
零件公差等級
低
一般
可達IT13~IT10級
可達IT10~IT8級
零件特點
尺寸不受限制厚度不受限制
中小型尺寸厚度較厚
小零件厚度0.2~6mm可加工復雜零件,如寬度極小的異形件
形狀與尺寸受模具結構與強度限制,尺寸可以較大,厚度可達3mm
零件平面度
低
一般
中小型件不平直,高質量制件需較平
由于壓料沖件的同時得到了較平,制件平直度好且具有良好的剪切斷面
生產(chǎn)效率
低
較低
工序間自動送料,可以自動排除制件,生產(chǎn)效率高
沖件被頂?shù)侥>吖ぷ鞅砻嫔希仨毷謩踊驒C械排除,生產(chǎn)效率較低
安全性
不安全,需采取安全措施
比較安全
不安全,需采取安全措施
模具制造工作量和成本
低
比無導向的稍高
沖裁簡單的零件時,比復合模低
沖裁較復雜零件時,比級進模低
適用場合
料厚精度要求低的小批量沖件的生產(chǎn)
大批量小型沖壓件的生產(chǎn)
形狀復雜,精度要求較高,平直度要求高的中小型制件的大批量生產(chǎn)
根據(jù)分析結合表分析:
方案一模具結構簡單,制造周期短,制造簡單,但需要兩副模具,成本高而生產(chǎn)效率低,難以滿足大批量生產(chǎn)的要求。
方案二只需一副模具,生產(chǎn)效率高,操作方便,精度也能滿足要求,模具制造工作量和成本比較高。適合大批量生產(chǎn)。
方案三只需一副模具,制件精度和生產(chǎn)效率都較高,且工件最小壁厚大于凸凹模許用最小壁厚模具強度也能滿足要求。沖裁件的內(nèi)孔與邊緣的相對位置精度較高,板料的定位精度比方案三低,模具輪廓尺寸較小。
通過對上述三種方案的分析比較,該工件的沖壓生產(chǎn)采用方案二為佳。
四、目標、主要特色及工作進度
由零件圖可知,零件是以2個mm的凸包定位,腰圓孔用于側蓋的裝配,故腰圓孔位置是該零件需要保證的重點。另外,該零件屬隱蔽件,被側蓋完全遮蔽,外觀上要求不高,只需平整。
工作進度:
第一周~第二周 查閱文獻、熟悉相關軟件使用,撰寫開題報告;
第三周 相關外文文獻閱讀與翻譯;
第四周~第五周 接口件沖壓工藝分析及沖裁工藝方案確定;
第六周 必要的裁減工藝計算;
第七周~第八周 模具結構型式及其主要零部件結構尺寸確定;
第八周~第十四周 模具總裝圖設計
第十五周~第十六周 模具主要零件的工作圖設計
第十七周 答辯準備及畢業(yè)答辯
五、參考文獻
[1] 張如華 等主編. 沖壓工藝與模具設計. 北京:清華大學出版社,2006
[2] 鍛壓學會 編. 鍛壓手冊第2卷 沖壓(第3版). 北京:機械工業(yè)出版社,2008
[3] 王孝培 主編. 沖壓手冊(第2版). 北京:機械工業(yè)出版社,1995
[4] 編寫組 編. 沖模設計手冊. 北京:機械工業(yè)出版社,1991
[5] (日)編委會 編. 沖壓加工技術手冊. 谷維忠等 譯. 北京:輕工業(yè)出版社,1988
[6] 鄭可锽 主編. 實用沖壓模具設計手冊. 北京:宇航出版社,1990
[7] 李天佑編. 沖壓模具圖冊. 機械工業(yè)出版社,198?
[8] 沖模設計應用實例. 北京:機械工業(yè)出版社,1999
[9] Fuh-Kuo Chen, Yeu-Ching Liao. Finte element anaysis of draw-wall wrinking in a stamping die design [A]. VIII International Conference on Computational Plasticity,Barcelona, 2005
軸架沖壓工藝及模具的設計
摘要:沖壓成型是金屬成型的一種重要方法,它主要適用于材質較軟的金屬成型,可以一次成型形狀復雜的精密制件。本課題就是將軸架作為設計模型,將冷沖模具的相關知識作為依據(jù),闡述冷沖模具的設計過程。
首先,對軸架的工藝性能進行分析,提出了三種可行的沖壓工藝方案。通過對三種方案的分析比較,最終確定采用第二種方案,選定“沖孔-彎曲-落料,級進模生產(chǎn)”的沖壓工藝路線。然后,按選定的工藝路線進行主要參數(shù)的工藝計算。確定模具的結構。即模架型式、導向方式、毛坯定位、卸料、推料、壓料、出件方式等。隨后,確定模具主要零部件的結構與尺寸。并在此基礎上繪制裝配圖和零件工作圖。最后,確定壓力機類型及主要參數(shù)。以達到預期效果。
關鍵詞:沖壓模具 軸架 模具設計
Axis frame stamping process and die design
Abstract: Stamping is an important method of metal forming, it is mainly applied to relatively soft metal forming, can be a molding of precision parts of complex shape. This topic is to stand as a design axis model, Die related knowledge as a basis to explain the design process of Die.
First, the performance of the shaft frame analysis of the process, put forward three possible solutions stamping process. Through analysis and comparison of three programs, and ultimately determine the use of the second option, select "Punching - Bending - Blanking, progressive die production of" stamping process route. Then, according to the selected process route for the main parameters of the process calculation. Determine the structure of the mold. The mold pattern, oriented approach, rough positioning, unloading, pushing material, press materials, the pieces of methods. Subsequently, to determine the main components of the mold structure and size. On this basis, assembly drawing and parts on the working drawings. Finally, determine the type and presses the main parameters. To achieve the desired effect.
Keywords: stamping die design crel Mold Design
Signature of Supervisor:
Heat Treatment of Die and Mould Oriented Concurrent Design LI Xiong,ZHANG Hong-bing,RUAN Xue—yu,LUO Zhong— hua,ZHANG Yan Abstract: Many disadvantages exist in the traditional die design method which belongs to serial pattern. 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 treatment process. Heat treatment CAD/CAE was integrated with concurrent circumstance and the relevant model was built. These investigations can remarkably improve efficiency, reduce cost and ensure quality of R and D for products. Key words:die design; heat treatment; mould 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 mould 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 and cost,modern die and mould should be designed and manufactured perfectly.Therefore more and more advanced technologies and innovations have been applied,for example,concurrent engineering,agile manufacturing virtual manufacturing,collaborative design,etc. Heat treatment of die and mould is as important as design,manufacture and assembly 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,heat 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 such as over—hard and—soft and assembly.Traditionally the heat 南昌航空大學科技學院 1 treatment process was made out according to the methods and properties brought forward by designer.This could make the designers of die and mould and heat treatment diverge from each other,for the designers of die and mould could not fully realize heat treatment process and materials properties,and contrarily the designers rarely understood the service environment and designing thought. These divergences will impact the progress of die and mould to a great extent. Accordingly,if the process design of heat treatment is considered in the early designing stage,the aims of shortening development period,reducing cost and stabilizing quality will be achieved and the sublimation of development pattern from serial to concurrent will be realized. 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 the error.The concurrent pattern has dismissed the defect of serial pattern,which bring about a revolution against serial pattern. In the present work.the heat treatment was integrated into the concurrent circumstance of the die and mould development,and the systemic and profound research was performed. 1 Heat Treatment Under Concurrent Circumstance The concurrent pattern 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 former 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 die and mould and the market foreground. Whereas in the concurrent pattern,the relations among departments are close, the related departments all take part in the development progress of die and mould and have close intercommunion with purchasers.This is propitious to elimination of the conflicts between departments,increase the efficiency and reduce the cost. 南昌航空大學科技學院 2 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 is favorable to optimizing the heat treatment process and making full use of the potential of the materials. 2 Integration of Heat Treatment CAD/CAE for Die and Mould It can be 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 and 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 burning),and then the heat treatment process is judged if the optimization is made according to the result reappeared by stereoscopic vision technology.Moreover tool and clamping apparatus CAD and CAM are integrated into this system. 南昌航空大學科技學院 3 The concurrent engineering based integration frame can share information with other branch.That makes for optimizing the heat treatment process and ensuring the process sound. 2.1 3-D model and stereoscopic vision technology for heat treatment The problems about materials,structure and size for die and mould can be discovered 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 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—conducting algorithm models for local heating complicated impression and asymmetric die and mould,and M ARC software models for microstructure transformation was used.Computer can present the informations of temperature, microstructure and stress at arbitrary time and display the entire transformation procedure in the form of 3-D by coupling temperature field,microstructure field and stress field.If the property can be coupled,various partial properties can be predicted by computer. 2.2 Heat treatment process design 南昌航空大學科技學院 4 Due to the special requests for strength,hardness , surface roughness and distortion during heat treatment for die and mould,the parameters including quenching medium 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 determine the parameters by computer fully. Since computer technology develops quickly in recent decades,the difficulty with large—scale calculation has been overcome.By simulating and weighing the property,the cost and the required period after heat treatment.it is not difficult to optimize the heat treatment process. 2.3 Data base for heat treatment A heat treatment database 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 predict 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 compositions,properties and home and abroad grades parallel tables. The process database includes heat treatment criterions,classes,heat preservation time and cooling velocity.Based on the database,heat treatment process can be created by inferring from rules. 南昌航空大學科技學院 5 2.4 Tool and equipment for heat treatment After heat treatment process is determined,tool and equipment CAD/CAE system transfers the information 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 which there is no man—made interference. 3 Key Technique 3.1 Coupling of temperature,microstructure,stress and property Heat treatment procedure is a procedure 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.Transformation 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 model has not been built.Many models fit the test nicely, but they cannot be put into practice.Difficulties with most of models are solved in analytic solution,and numerical method is employed so that the inaccuracy of calculation exists. Even so,comparing experience method with qualitative analysis,heat treatment simulation by computer makes great progress. 南昌航空大學科技學院 6 3.2 Establishment and integration of models 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 each 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 model will change in case the cell model changes.In fact,it belongs to the relation of data with die and mould.After heat treatment model is integrated into the system,it is no more an isolated unit but a member which is close to other models in the system.After searching,calculating and reasoning from the heat treatment database,procedure for heat treatment,which is restricted by geometric model,manufacture model for die and mould and by cost and property,is obtained.If the restriction is disobeyed, the system will send out the interpretative warning. All design cells are connected by communication network. 3.3 Management and harmony among members 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 managed 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 should be made out and monitor mechanism should be established.The obstruction can be duly excluded in case the development is hindered. Agile management and harmony redound to communicating information, increasing efficiency,and reducing redundancy.Meanwhile it is beneficial for exciting creativity,clearing conflict and making the best of resource. 4 Conclusions 南昌航空大學科技學院 7 (1) Heat treatment CAD/CAE has been integrated into concurrent design for die and mould and heat treatment is graphed,which can increase efficiency,easily discover problems and clear conflicts. (2) Die and mould development is performed on the 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. (3) Making out correct development schedule and adjusting it in time can enormously shorten the development period and reduce cost. References: [1] ZHOU Xiong-hui,PENG Ying-hong.The Theory and Technique of Modern Die and Mould Design and Manufacture[M].Shanghai:Shanghai Jiaotong University Press 2000(in Chinese). [2] Kang M,Park& Computer Integrated Mold Manufacturing[J].Int J Computer Integrated Manufacturing,1995,5:229-239. [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].Int J Product Research,1993,31(11):2709—2725. [4] LI Xiang,ZHOU Xiong-hui,RUAN Xue-yu.Application of Injection Mold Collaborative Manufacturing System [J].JournaI of Shanghai Jiaotong University,2000,35(4) : 1391-1394. [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. [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. 文獻出處: 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 南昌航空大學科技學院 8 譯文 模具熱處理及其導向平行設計 李雄,張鴻冰,阮雪榆,羅中華,張艷 摘要: 在一系列方式中,傳統(tǒng)模具設計方法存在許多缺點。眾所周知,熱處理對 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,一種新的 模具熱處理工藝并行設計方法已經(jīng)被開發(fā)出來了。熱處理 CAD/CAE 技術是集 成了并行環(huán)境和有關模型而建立的。這些調查研究可以顯著提高效率,降低 成本,并保證產(chǎn)品質量達到 R 和 D 級。 關鍵詞:模具設計;熱處理;模具 傳統(tǒng)模具設計主要是依照自身實踐經(jīng)驗或依照部分實踐經(jīng)驗,而不是制造工藝。 在設計完成之前,模具方案通常要被一次又一次的改進,于是有些缺點便出現(xiàn),例 南昌航空大學科技學院 9 如開發(fā)時期長,成本高和實際效果不明顯。由于對精確性、使用壽命、開發(fā)期和費 用的嚴格要求,先進的模具要求設計和制造得十分完善。因此越來越先進的技術和 創(chuàng)新方法被應用其中,例如并行工程、敏捷制造業(yè)、虛擬制造業(yè)、協(xié)同合作設計等。 模具的熱處理與模具設計,制造和裝配同樣重要。因為它對模具的制造裝配和 使用壽命又及其重要的影響。模具設計與制造發(fā)展十分迅速,但是熱處理發(fā)展卻嚴 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。不切實際的熱處理將導致模具材料過硬或過軟,同時影響模具裝配性能。 傳統(tǒng)的熱處理工藝是按照設計師提出的方法和特性制作出來的。這樣會使模具設計 師和熱處理工藝師意見產(chǎn)生分歧,而模具設計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)境和設計思路。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計放在設計階段之前, 則縮短開發(fā)周期,減少花費和保證質量等目標將會被考慮,而且從串行到并行的發(fā) 展模式也將會實現(xiàn)。 并行工程是以計算機集成系統(tǒng)作為載體,在開始以后,每個階段和因素都被看 作如制造、熱處理、性能等等,以避免出現(xiàn)錯誤。并行模式已經(jīng)摒除了串行模式的 缺陷,由此帶來了一場對串行模式的革命。 在當前的工作中,熱處理被集成到了模具開發(fā)的并行環(huán)境中,同時也正在進行 這種系統(tǒng)性和深入性的研究。 1.熱處理下的并行環(huán)境 并行模式與串行模式存在根本的不同(見圖 1) 。對于串行模式,設計者大多考 慮的是模具的結構與功能,但很難考慮相關的工藝,以致前者的錯誤很容易蔓延到 后面。與此同時,設計本門很少與裝配,預算會計和銷售部門溝通。這些問題當然 會影響模具的開發(fā)進度和市場前景。然而在并行模式中,不但以上部門關系聯(lián)系密 切,所有參加模具開發(fā)的部門都與買家有密切的交流。這有助于協(xié)調各部門消除矛 盾,提高工作效率,同時降低成本。 (a) 南昌航空大學科技學院 10 (b) (a)串行模式 (b)并行模式 圖 1.基于摸具開發(fā)的串行工程與并行工程系統(tǒng)框架示意圖 并行環(huán)境下的熱處理工藝不是在方案和工件確定以后,而是在模具設計的時候 制定出來的。這樣的話,將有利于優(yōu)化熱處理工藝,充分利用材料。 2.模具熱處理 CAD/CAE 一體化 從圖 2 中可以看出,熱處理工藝的設計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)熱處理工藝過程產(chǎn)生的熱處理 CAD 和熱處理 CAE 模塊將對于 零件圖,熱處理以后模擬溫度場的微觀結構分析和可能出現(xiàn)的缺陷(例如過熱,燒 傷)自動劃分網(wǎng)絡,如果優(yōu)化是根據(jù)立體視覺技術的結果重新出現(xiàn),則這項熱處理 工藝已經(jīng)被審核。而且工具與夾具的 CAD 和 CAE 也集成于這種系統(tǒng)中 。 南昌航空大學科技學院 11 圖 2.并行工程熱處理 CAD/CAE 一體化系統(tǒng)框架示意圖 以并行工程為基礎的集成模式可以與其它類似模式共享信息。這樣使熱處理工 藝得到優(yōu)化,并確保改工藝準確。 2.1 采用三維模型和立體視覺技術的熱處理 在形成模具的基礎上,材料,結構和尺寸的問題能通過熱處理三維模型盡快發(fā) 現(xiàn)出來。在熱處理過程中,模具加熱條件和相變條件是切合實際的,因為通過計算 相變熱力、相變動力、相應力、熱應力、傳熱速度、流體動力等已經(jīng)取得重要突破。 例如,能進行局部復雜表面和不對稱模具的三維熱傳導模型計算,和能進行微觀結 構轉變的 MARC 軟件模型。計算機能夠在任何時間提交溫度,微觀結構和應力的信 息,并通過連接溫度場微觀結構領域和力場來顯示三維形式的全部改變過程。如果 再加上這種特性,則各部分性能都能通過計算機預見。 2.2 熱處理工藝設計 由于對強度和硬度,表面粗糙度和模具熱處理變形的特殊要求,淬火介質的種 類、淬火溫度、回火溫度和時間等參數(shù)特性必須經(jīng)過適當?shù)倪x擇,以及是否使用表 面淬火或化學熱處理,這種特性必須準確的制定下來。自從計算機技術在最近幾十 年迅速的發(fā)展,難以進行大型計算已經(jīng)成為過去。通過模擬和仔細考慮熱處理特性, 熱處理后的成本和所須時間,這些都并不難優(yōu)化熱處理工藝。 2.3 熱處理數(shù)據(jù)庫 熱處理數(shù)據(jù)庫在圖 3 中描述。數(shù)據(jù)庫是制定熱處理工藝的基礎。一般來說,熱 處理數(shù)據(jù)庫分為材料數(shù)據(jù)庫和工藝數(shù)據(jù)庫。通過材料和工藝來預測特性已成為一種 必然的趨勢。盡管很難建立一個特性數(shù)據(jù)庫,但通過一系列的測試來建立數(shù)據(jù)庫是 必要的。材料數(shù)據(jù)庫包括材料牌號、化學成分、性能和國內(nèi)外同級別目錄表。工藝 南昌航空大學科技學院 12 數(shù)據(jù)庫包括熱處理標準、種類、保溫時間和冷卻溫度?;跀?shù)據(jù)庫,熱處理工藝可 以通過推理規(guī)則創(chuàng)造出來 。 圖 3.熱處理數(shù)據(jù)庫 2.4 熱處理工具和設備 在熱處理工藝確定以后,工具及設備 CAD/CAE 系統(tǒng)傳送設計和制造的數(shù)值信 息來控制裝置。通過快速模具成型,可靠的工具和夾具都能被確定。整個程序通過 網(wǎng)絡傳送,不存在任何人為干擾。 3.關鍵技術 3.1 溫度,微觀結構,應力和特性的聯(lián)系 熱處理程序是一個溫度,微觀結構和應力互相作用的程序。三方面都能影響材 料特性(見圖 4) 。在加熱和冷卻期間,當微觀結構轉變時熱應力和相變遲早會出現(xiàn)。 微觀結構溫度相變和溫度-微觀結構-應力特性相互影響。對相互作用的四個因素 的調查已經(jīng)取得很大的發(fā)展,但普通的數(shù)學模型還沒有建立。許多模型能很好的滿 足測試結果,但不能投入到實踐當中。大部分模型的難點是用分析的方法處理的, 同時數(shù)值方法也運用了,導致存在不準確的計算 。 南昌航空大學科技學院 13 圖 4.熱處理工藝圖解 即使如此,把經(jīng)驗方法與定性分析相比較,通過計算機來進行熱處理模擬取得 了很大的進展。 3.2 模型的建立和融合 在模具的開發(fā)過程中,涉及到設計、制造、熱處理、裝配、維修等。它們應該 有自己的數(shù)據(jù)庫和模型。它們通過事物的內(nèi)在聯(lián)系建立模型,互相串聯(lián)起來,盡管 建立和運用動態(tài)推理機制,但其目的在于完成優(yōu)化設計。產(chǎn)品模型和其它模型的聯(lián) 系已被建立。如果細小組織模型發(fā)生改變,則產(chǎn)品模型也將改變。事實上,它屬于 數(shù)據(jù)庫與模具之間的聯(lián)系。當熱處理模型集成到系統(tǒng)以后,它已不再是一個孤立的 單位,而是一個部分,同時在系統(tǒng)中接近其它模型。在搜查后,熱處理數(shù)據(jù)庫的計 算和推理能力,熱處理程序都被幾何模型,模具制造模型和預算所限制,這是通行 的。如果這種限制不服從,系統(tǒng)會發(fā)出解釋性的警告。 所用設計的細小組織都是通過互連網(wǎng)連接的。 3.3 各部分之間的管理和協(xié)調 復雜的模具需要其中各項目組之間密切合作。因為考慮到模具的開發(fā),各部分 都存在缺點,它必須得到管理和協(xié)調。首先,各項目組應該確定其本身的控制條件 和資源要求,同時了解不同環(huán)境下的工作程序,以避免發(fā)生沖突。其次,要提出開 發(fā)計劃和建立監(jiān)控機制。如果開發(fā)受到限制則可逐步排除。 敏捷管理和協(xié)調有助于交流信息,提高效率和減少材料。同時這有利于激發(fā)人 的創(chuàng)造力,消除阻礙和制定出最好的方法。 4.總結 ⑴熱處理 CAD/CAE 技術已被集成到模具并行設計中去,同時熱處理已被制成 圖表,這有利于提高效率,較易發(fā)現(xiàn)問題并解決問題。 ⑵模型的開發(fā)已在同一個平臺運行。在這個平臺中,當熱處理工藝制定出來后, 設計人員可獲得相關信息和轉讓部分信息到其它設計部門。 ⑶制定出正確的開發(fā)計劃并按時調整可以極大縮短開發(fā)周期和降低成本。 文獻出處: 李雄,張鴻冰,阮雪榆,羅中華,張艷.模具熱處理及其導向平行設計[J]. 鋼鐵研究學報英文 南昌航空大學科技學院 14 版,2006,13(1):40-43,74
收藏