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1、<p>  New Trends and Problems in Material Processing Machine Design Theory</p><p>  WANG Ai-lun ,DUAN Ji-an ,HUANG Ming-hui ,ZHONG Jue</p><p>  (College of Mechanical & Electronic Engin

2、eering ,</p><p>  Central South University ,Changsha 410083 ,Hunan China)</p><p>  Abstract :</p><p>  Based on reviewing the historical background, prospecting for the development

3、trend ,analyzing the complicacy and mechanism and summing up some achievements and experiences in scientific research , several new problems and the possible direction of development in material processing technology and

4、 machine are proposed ,such as ,producing new concept materials possessing some specific and extraovdinary properties by means of integrating and coalescing conelative frontier science and technology ;a</p><p&

5、gt;  Keywords: interface; extraordinary physical field; procession machine ; function material</p><p>  1 The Time Background of Material Processing Machine</p><p>  In the long span of history

6、of human progress ,many tools ,machines and methods were created and a variety of materials with different properties were processed. Materials and its processing have become one of pillar and driving force of mankind pr

7、ogress. In pace with multi - polar competition in current world and people’s striving perseveringly for happier life ,material function goes beyond unceasingly men’s knowledge and imagination ,for example ,cryptic functi

8、on material ,semiconductor mater</p><p>  (1) Creating material processing machine with extraordinary physical field for processing material with special texture structures and functions. For example ,applic

9、ations of thermal energy and mechanical energy are breaking through unceasingly technology limit ,and some non - tradition energy ,such as microwave ,chemical energy , bioenergy , etc. , are introduced into material proc

10、essing procedure one after another ,so that some material processing machines with extraordinary energy circumstanc</p><p>  (2) Breaking through traditional physical limits and integrating melting ,solidify

11、ing ,plastic deformation and heat treatment to obtain special function of material and cut down expenses[3 ] . For example ,near - net shaping material processing technology , such as fast rolling , spraying deposition ,

12、over - plastic molding , injection molding , high energy beam ,etc ,is applied.</p><p>  (3) Material processing process is forged ahead in the direction of high speed ,heavy - duty and high accuracy online

13、control ,for instance , the rolling speed goes up to 130 m·s - 1 ,the deformation pressure rises up to 300 MPa ,accuracy of dimension up to 0.1μm ,accuracy of shape up to 0. 1 I ,strength accuracy comes up to 0.1 MP

14、a. For these reasons ,it is necessary for material processing machine design theory to integrate and coalesce ingeniously correlative frontier science and technology t</p><p>  2 Due Functions of New Concept

15、 Material Processing Machine</p><p>  (1) To have the ability to produce and bear extraordinary physical field and transmit extraordinary energy flow with the aim of providing extraordinary physical circumst

16、ances necessary for new concept material processing. For example ,high gradient temperature field with the speed of cool - down of work interface which exceeds 104~106 K·s - 1 , line wave and pulse complex exerted i

17、n solidifying - deforming area , super - strength contact stress field of material forming interface ,turbulent flow</p><p>  (2) To have the ability to work in critical state so that high stability and idea

18、l performance of processing machine is ensured under the circumstance of reinforced technological condition and multi - field coupling operation. For example ,chatter suppressing capability of fast ultra - thin rolling u

19、nder the condition of boundary lubricating state[5 ] ,the capability of self - excited vibration suppressing under the condition of special friction state ,synergism stability and disturbance stabili</p><p>

20、  (3) To have the ability to accurately control the material processing in order to obtain low loss ,high efficiency and high quality of material processing. For example , super - high accuracy on - line monitor of produ

21、cts form ,on – line monitor and on - line adjustment of products texture and properties ,precision coordination control of multi - procedure , on - line monitor of micro - orientation of metal plastic deformation ,etc. [

22、4 ] ,are ensured. Some products accuracy index may be enumerat</p><p>  3  Science Problems and Study Contents of Metal Material Processing Machine</p><p>  Under the Circumstance of Extraordina

23、ry Physical Field</p><p>  In view of these facts and background mentioned above ,several new research topics can be advanced as follows.</p><p>  3. 1 Coupling Heat Transfer Mechanism of Multi

24、- Phase Interface Temperature - Stress Field</p><p>  A brand - new microstructure can be obtained through continuously large deformation and fast solidifying when melting metal is in critical state of liqui

25、d solid. At this very moment ,high density heat flow and dynamic heat resistance are present in material processing circumstance . A basic theory problem of designing this kind of machine is to study mechanism of heat tr

26、ansmittance and energy conversion ,and to establish mathematical model .</p><p>  3. 2 Friction Constraint Mechanism of Plastic Flow Interface of Material Processing Machine</p><p>  The couplin

27、g between operation mechanism and workpiece is very complicated because plastic flow is present in processing interface. The interface state , determined by velocity , load thermodynamic process , elasticity of operation

28、 mechanism ,plasticity of workpiece ,dynamic behaviour of interface sticking - sliding and partial hydrodynamic lubrication ,etc ,affect and form friction constraints mechanism peculiar to material processing machine ,be

29、cause these constraints present strong non - line</p><p>  3. 3 Multi - Body Non - Linear Contact Mechanism Under the Condition of Extra - High Pressure Field</p><p>  To build the super strengt

30、h pressure field on large area is one of basic function of material processing machine , and it is also necessary to form by once large - size structure element (such as spacecraft , intercontinental vehicles ,car and la

31、rge - scale aeroplane etc) . The ability to build super strong pressure field is one of important feature and the base of independent national defense. Under the circumstance of super strength pressure field ,multi - bod

32、y strong nonhertz contact and non </p><p>  3. 4 Load Distribution Law in Multi - Sliding Pair With Structure Bias Load</p><p>  With regard to statically indeterminate structure ,load distribut

33、ion of constraint point is determined by deformation compatibility condition. However ,concerning some plane large - size statically indeterminate structure with sliding degree of freedom in third dimension ,load distrib

34、ution can not be determined by deformation compatibility condition. Thus new theory basis will be provided by analyzing of contact behaviour and mechanism of sliding pair (such as creep ,force of friction ,integral </

35、p><p>  3. 5 Coupling Mechanism and Stability of Multi - Physical Fields in Material Processing Systems</p><p>  In the wake of system function becoming more and more diversified , conventional tec

36、hnology limits in material processing machine is being broke through unceasingly ,system structure also becomes increasingly complicated ,and system performance becomes increasingly multi - causal . For example ,any inst

37、antaneous state of roller in fast rolling mills is affected by elastic deformation ,plastic flow ,heat transfer process , hydro - dynamic lubrication process ,interface physical chemistry molecula</p><p>  3

38、. 6 Multi - Technology Integration and Coalescence of Accurate Control</p><p>  The material processing machine ,which operate under the circumstance of extraordinary physical field ,is a complicated large -

39、 scale system ,and some parameters of the system vary on feasible field boundary ;thereby ,to keep under accurate control and adjustment of multi field circumstance ,multi - dimension coordination ,multi - energy convers

40、ion , multi - level information transfer ,interface multi - process coupling ,etc. is of much significance. Since a variety of multi - interaction exists</p><p>  3. 7 Quasi - Reality Design and Concurrent D

41、esign Based on Knowledge Innovation Systems</p><p>  Digitalization and visualization of material processing technology will promote immediately the quality of design, operation and control . Therefore optim

42、ization of material processing technology and material processing machine by means of realization of virtual simulation of processing procedure through quasi - reality design and concurrent design is one of our pressing

43、study subjects.</p><p>  3. 8 Mechanical Behavior of Special Function Materials in the Extraordinary Physical Field</p><p>  Many key elements and parts in material processing machine are often

44、under the circumstance of super strong force field ,temperature field ,electronic magnetic field and flow field ,and must have the functions of constructing special physical interface. However ,it is difficult for common

45、 single - substance material such as metal ,ceramic polymer ,etc. to have both high index of single property and excellent overall quality. Therefore we need to use certain material with new functions for key po</p>

46、;<p>  材料制備機(jī)械設(shè)計(jì)理論中的新趨勢(shì)和新問題</p><p>  王艾倫,段吉安,黃明輝,鐘 掘</p><p>  (中南大學(xué)機(jī)電工程學(xué)院,湖南長(zhǎng)沙 410083)</p><p><b>  摘 要:</b></p><p>  在全面綜述材料制備機(jī)械技術(shù)及設(shè)備發(fā)展動(dòng)態(tài)的基礎(chǔ)上,提出了研究領(lǐng)

47、域的幾個(gè)新問題和發(fā)展方向,如通過集成和融合現(xiàn)代相關(guān)前沿科學(xué)和技術(shù),生產(chǎn)具有超常和特殊性能的新概念材料等,并進(jìn)行了簡(jiǎn)要分析和討論.</p><p>  關(guān)鍵詞:界面;超常物理場(chǎng);制備機(jī)械;功能材料</p><p>  1.機(jī)械材料加工的時(shí)代背景</p><p>  在人類進(jìn)步的一段長(zhǎng)時(shí)間范圍內(nèi),許多工具、機(jī)械和方法被提出來;不同的原料用不同的工具來加工。原料及其處理過

48、程已經(jīng)變成了推動(dòng)人類進(jìn)步不可缺的一部份。在當(dāng)前世界中日益激烈的競(jìng)爭(zhēng)和人們追求幸福生活的今天,物質(zhì)的功能已經(jīng)遠(yuǎn)遠(yuǎn)超出了人類現(xiàn)有的并不斷增長(zhǎng)的知識(shí)及想象。例如:神秘原料功能,半導(dǎo)體材料,原料能量有吸力的材料,在航空領(lǐng)域中占有70%份額的強(qiáng)力鋁合金4~5um的薄金屬片,用各向異性深沖壓金屬板在1%以下;電子鋁箔與強(qiáng)耐熱鋁合金已經(jīng)被應(yīng)用到航空、宇宙及深海領(lǐng)域中,等等;在原料加工加工領(lǐng)域中不同的時(shí)間段里,材料重要發(fā)展趨勢(shì)就這樣形成了:</p

49、><p> ?。?)在特殊的物理領(lǐng)域里制造原料加工機(jī)械,是為了能有特殊的質(zhì)地結(jié)構(gòu)和輔助性的加工功能。例如:運(yùn)用熱能和機(jī)械能能夠突破科學(xué)技術(shù)的極限,將一些不常用的能量,例如:微波、化學(xué)能、生物能等等,一個(gè)接一個(gè)的被引入到材料加工中來,因此一些加工特殊能量原材料的加工設(shè)備就被制造出來了。</p><p> ?。?)突破傳統(tǒng)的物質(zhì)限制,將溶化、凝固、造型一體化,然后加熱得到具有特殊功能的原料,這樣就

50、可以降低加工費(fèi)用。例如:材料加工整形技術(shù),比如像快速翻滾,噴霧處理、塑膠成型、噴射造型法、高能量射束等等被應(yīng)用。</p><p> ?。?)原料加工處理正在向高速、重載和高精度在線控制方向上邁進(jìn)。例如:軋制速度達(dá)到130m/s,壓力變形已達(dá)到300MPa,尺寸精度達(dá)到了0.1um,成型精度已達(dá)到0.1i;濃度精度已達(dá)到0.1MPa。由于這些原因,原料加工機(jī)械設(shè)備設(shè)計(jì)理論將科學(xué)與技術(shù)相關(guān)聯(lián)的領(lǐng)域有機(jī)的結(jié)合起來設(shè)計(jì)生

51、產(chǎn)一中新概念材料加工設(shè)備是可能的。</p><p>  2.對(duì)于新概念材料加工設(shè)備的期望功能</p><p> ?。?)要有能力生產(chǎn)具有特殊物質(zhì)的領(lǐng)域;能傳送那些對(duì)于新概念材料加工在特定的物質(zhì)環(huán)境下是非常必要的特殊能流。例如:在高溫環(huán)境下能使那些高溫波或者脈沖以超過104~106K/s的速度冷卻下來;將外表面的凝固、變形合成一體,然后在將超強(qiáng)接觸面應(yīng)力重新組合成新的分界面;融化的大金屬薄片

52、的湍流;隨機(jī)的低頻率磁場(chǎng)用于金屬末加熱的微波、用于大量凝固的超聲波等等都已經(jīng)被應(yīng)用了。</p><p>  (2)有能力在臨界狀態(tài)下工作,因此高穩(wěn)定性和理想性能的處理設(shè)備是在加強(qiáng)技術(shù)條件和室外操作的保證。例如:禁止在潤(rùn)滑狀態(tài)下邊界上的搖晃;在特有的摩擦狀態(tài)下的抗震能力;有韌性的連接管的合力穩(wěn)定性和干擾穩(wěn)定性與軸相比更易驅(qū)動(dòng)系統(tǒng)。</p><p>  (3)有能力精確的控制原料加工而獲得低損

53、耗、高功率、高性能的原料加工。例如:精確的在線監(jiān)測(cè)產(chǎn)品成型;在線監(jiān)測(cè)和在線調(diào)整產(chǎn)品品質(zhì)和器具還有在線控制金屬、塑膠成型的程序。產(chǎn)品的精確度指數(shù)可以列舉如下:宏觀上精確度可達(dá)到0.1um,微觀上的晶狀體結(jié)構(gòu)非常均勻,濃度誤差在0.1MPa 。簡(jiǎn)而言之,擁有特別功能的新概念原料加工設(shè)備應(yīng)該被設(shè)計(jì)和生產(chǎn)出來。這樣的話,那些特別性能的原料就能被處理加工了。</p><p>  3.在特殊的物理領(lǐng)域和環(huán)境下金屬材料加工設(shè)備

54、的問題和需要學(xué)習(xí)的內(nèi)容</p><p>  由于這些原因和以上提到的背景,如下的一些新的研究主題應(yīng)該被改進(jìn):</p><p>  3.1 連接傳熱裝置和溫度應(yīng)力場(chǎng)的相界面</p><p>  當(dāng)融化金屬處于液體和固體的臨界狀態(tài)時(shí)通過連續(xù)的變形和快速凝固,一種全新的微觀結(jié)構(gòu)可以被獲得。在這個(gè)非常時(shí)刻,高濃度的熱流和動(dòng)態(tài)的熱阻力在材料加工處理中成了主要事項(xiàng)。關(guān)于設(shè)計(jì)這

55、個(gè)設(shè)備的基本理論問題是要學(xué)習(xí)核心傳動(dòng)系統(tǒng)合能量轉(zhuǎn)化和建立數(shù)學(xué)模型。</p><p>  3.2 材料加工設(shè)備表面粘流摩擦力的抑制</p><p>  操作裝置和工件的連接是相當(dāng)復(fù)雜的因?yàn)檎沉髯钃趿思庸け砻娼缑鎽B(tài)由周轉(zhuǎn)速度、熱力學(xué)處理工作量、操作裝置的彈性、工件的可塑性、滑性界面的動(dòng)態(tài)行為、局部水力的潤(rùn)滑油等等來決定。它們影響著材料加工設(shè)備抗摩擦裝置的成型。因?yàn)樗鼈儠?huì)會(huì)強(qiáng)制其產(chǎn)生很大的非線

56、性,這種強(qiáng)制會(huì)在瞬間被損壞或者是失諧,最后會(huì)導(dǎo)致動(dòng)態(tài)不穩(wěn)定性。因此提出了以下的問題:機(jī)械裝置的噪聲可能在晃動(dòng)的界面引起滑動(dòng)摩擦、不穩(wěn)定狀態(tài);在高速、重載和邊界潤(rùn)滑狀態(tài)下在光滑表面和旋轉(zhuǎn)式噴灌器之間的裝置抑制。潤(rùn)滑油薄膜吸收裝置和不斷再生的表面的物理化學(xué)行為;流變學(xué)的特征和操作參數(shù)之間的關(guān)系。</p><p>  3.3 在高壓場(chǎng)條件下非線性接觸式機(jī)械裝置</p><p>  在大范圍內(nèi)組

57、建一個(gè)超強(qiáng)力壓力場(chǎng)是材料加工設(shè)備的一個(gè)基本功能。當(dāng)然形成一個(gè)大結(jié)構(gòu)的元素也是可能的(例如太空船、大陸洲際間的交通工具、汽車、飛機(jī))。組建一個(gè)超強(qiáng)壓力場(chǎng)是最重要的特征之一,也是保衛(wèi)國(guó)家獨(dú)立最基本的裝備。在強(qiáng)壓力場(chǎng)環(huán)境下,接觸式和非線性摩擦將會(huì)產(chǎn)生;因此將會(huì)導(dǎo)致局部的永久的變形和不好的因素。在強(qiáng)壓力場(chǎng)下設(shè)計(jì)過程中,將會(huì)涉及到設(shè)備的設(shè)計(jì)新理論,例如:非接觸式、非線性摩擦機(jī)構(gòu)。</p><p>  3.4 負(fù)荷分配規(guī)律

58、</p><p>  關(guān)于超靜定結(jié)構(gòu),抑制點(diǎn)的負(fù)荷分配規(guī)律由相容性條件決定。雖然,關(guān)于那些大尺寸的、不定的、靜止的結(jié)構(gòu)在真實(shí)空間中是自由變化的,但負(fù)荷分配規(guī)律是不能決定相容性條件。因此新的基礎(chǔ)理論由分析接觸行為和變形裝置獲得(例如:摩擦力、變形相容性條件,等等)。</p><p>  3.5 耦合裝置和在材料加工系統(tǒng)中物理領(lǐng)域內(nèi)的穩(wěn)定性</p><p>  隨著系

59、統(tǒng)的功能越來越多元化;許多限制材料加工進(jìn)度的傳統(tǒng)技術(shù)正在不斷的被改善;系統(tǒng)結(jié)構(gòu)也逐漸變得越來越復(fù)雜,系統(tǒng)性能變得越來越好。例如:鋼扎廠的快速瞬間反轉(zhuǎn)受彈性形變、粘流、散熱處理、水動(dòng)力潤(rùn)滑處理的,物理化學(xué)分子狀態(tài)的影響。另外,機(jī)電的耦合在處理系統(tǒng)中已經(jīng)超出了傳統(tǒng)的概念;例如,一些奇特的現(xiàn)象(微小的變化可以引起很大的變化)已經(jīng)出現(xiàn);因此,滾筒操作的不穩(wěn)定性可能會(huì)導(dǎo)致混亂。所以,這個(gè)主題將會(huì)在機(jī)械裝置的物理領(lǐng)域中,在處理系統(tǒng)穩(wěn)定性的影響和加工

60、助劑質(zhì)量上被提及和充分關(guān)注;</p><p>  3.6 技術(shù)綜合和合并精準(zhǔn)的控制</p><p>  在特定的物理?xiàng)l件下進(jìn)行操作的材料加工設(shè)備是一個(gè)相當(dāng)復(fù)雜系統(tǒng),一些系統(tǒng)的參數(shù)在領(lǐng)域的邊界上也是可以改變的;因此在領(lǐng)域環(huán)境下精確的控制與調(diào)整,調(diào)和尺寸,能量轉(zhuǎn)換,信息傳遞,界面耦合等等是非常重要的。因?yàn)樵诳刂颇P椭卸喾N交互作用的存在,根據(jù)退耦控制模型而建立綜合框架是必要的;精確的控制基于綜

61、合技術(shù)。</p><p>  3.7 優(yōu)化的和創(chuàng)新的設(shè)計(jì)基于創(chuàng)新的知識(shí)</p><p>  材料加工技術(shù)能促進(jìn)產(chǎn)品的設(shè)計(jì)質(zhì)量的提高。最優(yōu)化的材料加工技術(shù)和材料加工設(shè)備意味著實(shí)現(xiàn)實(shí)質(zhì)的仿真通過類似的設(shè)計(jì)和一致的設(shè)計(jì)是我們學(xué)習(xí)的主題。</p><p>  3.8 在特殊的領(lǐng)域里機(jī)械裝置的特殊功能和應(yīng)用</p><p>  一些重要的元素和部分

62、在材料加工設(shè)備中常常在強(qiáng)力場(chǎng)、溫度場(chǎng)、電磁場(chǎng)和流場(chǎng)中工作,有建造特別物理界面的功能;雖然對(duì)那些普通單一的物質(zhì)象金屬、陶瓷等擁有單一的高指數(shù)和卓越的總質(zhì)量是很困難的。因此我們需要在重要部位采用具有新功能的原料;例如:尺度功能有傾向的材料是想當(dāng)可貴的。由于這些原因,學(xué)習(xí)基本法律和以上提到的具有這些功能的機(jī)械裝置;例如:強(qiáng)調(diào)分配功能、破壞機(jī)理和在特定領(lǐng)域中的設(shè)計(jì)標(biāo)準(zhǔn),靜態(tài)(動(dòng)態(tài))的硬度和阻尼,模糊設(shè)計(jì)和明朗設(shè)計(jì)處理系統(tǒng)構(gòu)成了有斜度的材料,等等

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