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1、? ? 第 24卷 ? 第 4 期 ? 吉首大學(xué)學(xué)報(bào)( 自然科學(xué)版) Vol. 24? No.4? ?? ? 2003 年 12 月 Journal of Jishou University ( Natural Science Edition) Dec. 2003? ?Article ID: 1007- 2985( 2003) 04- 0027- 04New Trends and Problems in Material Process

2、ing Machine Design Theory ?WANG A- i lun, DUAN J- i an,HUANG Ming -hui, ZHONG Jue( College of Mechanical and thereafter a brief discussion is given.Key words: interface; extraordinary physical field; processing machine;

3、 function materialCLC number: TH11? ? ? ? ? ? Document code: A1 ? The Time Background of Material Processing MachineIn the long span of history of human progress, many tools, machines and methods were created and a varie

4、ty of ma -terials with different properties were processed.Materials and its processing have become one of pillar and driving forceof mankind progress. In pace with multi- polar competition in current world and people?s

5、striving perseveringly forhappier life, material func tion goes beyond unceasingly men?s knowledge and imagination, for example, cryptic functionmaterial, se miconductor material, energy material, vibration- absorptive m

6、aterial, super- strength aluminum alloy ac -counting for 70 percent of application of aeronautics and space, metal foil of 4~ 5 ?m, deep drawing plate with anisotro -py below 1 percent, electronic aluminum foil with micr

7、o- orientation up to 95 percent, heat resisting aluminum alloywith super strong specific strength used in aeronautics, space and deep sea, etc. [ 1,2] Thus several important develop -ment trends with distinct time featur

8、es in material processing domain are shaped up as follo ws:( 1) Creating material processing machinewith extraordinary physical field for processing material with special tex -ture structures and functions. For exa mple,

9、 applications of thermal energy and mechanical energy are breaking throughunceasingly technology limit, and some non- tradition energy, such as microwave, chemical energy, bioenergy, etc. , areintroduced into material pr

10、ocessing procedure one after another, so that some material processing machines with e xtraor -dinary energy circumstance are produced.( 2) Breaking through traditional physical limits and integrating melting, solidifyin

11、g, plastic deformation and heattreatment to obtain special function of material and cut down expenses [ 3] . For e xample, near- net shaping material pro -cessing technology, such as fast rolling, spraying deposition, ov

12、er- plastic molding, injection molding, high energybea m, etc, is applied.? Received date: 2003- 06- 12Foundation item: Supported by Nati onal Natural Science Foundation of Chi na( 59835170) and State Key Project of Fund

13、amental Re -search( G1999064906)Biography: WANG A- i lun( 1960- ) ,was born in Changsha City, professor of College of Mechanical research area is modern machine design theory and making skill, dynamics of mechanical and

14、 Electronic sys -tem.instantaneously and thus dynamic instability is resulted in.Thus following problems can be put forward: Mechanism of ?spectre chatter? arose from sticking- sliding frictionand partial hydrodynamic lu

15、brication in rolling interface, instability condition and mechanism of constraint betweensmooth surface and rotating body under the circumstance of high speed, heavy- duty and boundary lubrication, Lubrica -tion film abs

16、orption mechanism and physical chemistry behaviour of interface of unceasingly regenerative surface, therelationship between rheological characteristic and machine opera tion parameters.3. 3 Multi- Body Non- Linear Conta

17、ct Mechanism Under the Condition of Extra- High Pressure FieldTo build the super strength pressure field on large area is one of basic function of material processing machine,and it is also necessary to form by once larg

18、e- size structure element ( such as spacecraft, intercontinental vehicles, carand large- scale aeroplane etc) . The ability to build super strong pressure field is one of important feature and the baseof independent nati

19、onal defense. Under the circumstance of super strength pressure field, multi- body strong non-hertz contact and non- linear friction will be produced, thus local permanent deformation and de grading of element ac -curacy

20、 may be led. New theory foundation of design of machine with super strength pressure field will be furnishedthrough study of multi- body strong non- hertz contact mechanism, multi- body non- linear friction mechanism ( s

21、uchas providing force- displacement mixed solving process of three- dimension multi- body) .3. 4 Load Distribution Law in Multi- Sliding Pair With Structure Bias LoadWith regard to statically indeterminate struc ture, lo

22、ad distribution of constraint point is determined by deformationcompatibility condition.However, concerning some plane large- size statically indeterminate structure with sliding de -gree of freedom in third dimension, l

23、oad distribution can not be determined by deformation compatibility condition.Thusnew theory basis will be provided by analyzing of contact behaviour and mechanism of sliding pair ( such as creep, forceof friction, integ

24、ral deformation compatibility condition, etc) .3. 5 Coupling Mechanism and Stability of Multi- Physical Fields in Material Processing SystemsIn the wake of system function becoming more and more diversified, c onventiona

25、l technology limits in material pro -cessing machine is being broke through unceasingly, system structure also becomes increasingly complicated, and systemperformance bec omes increasingly multi- causal. For e xample, an

26、y instantaneous state of roller in fast rolling mills isaffected by elastic deformation, plastic flow, heat transfer process, hydro- dynamic lubrica tion process, interface phys- ical chemistry molecular state and so on

27、[ 5] .In addition, electromechanical coupling in processing syste m have already gone beyond conventional concept, forinstance, some singular point phenomenon ( suc h as micro- variable can be transformed into macro- var

28、iable) , are pr -esent, thus roller operation instability may be led by perturbation [ 8] .Therefore, this subject will study the interaction mechanism of multi- physical field and the influence on process -ing system st

29、ability and processing material quality started with analysis of micro- state of executive body.3. 6 Multi- Technology Integration and Coalescence of Accurate ControlThe material processing machine, which operate under t

30、he circumstance of extraordinary physical field, is a c om -plicated large- scale system, and some parameters of the system vary on feasible field boundary; thereby, to keep underaccurate c ontrol and adjustment of multi

31、 field circumstance, multi- dimension coordination, multi- energy conversion,multi- level information transfer, interface multi- process coupling, etc. is of muc h significance. Since a variety ofmulti- interaction exist

32、s in control model, it is necessary to establish integration framework of coordination work ac -cording to decoupling of c ontrol model, so as to accurate control based on the multi- technology integration and c oales -c

33、ence is realized.3. 7 Quasi- Reality Design and Concurrent Design Based on Knowledge Innovation SystemsDigitalization and visualization of material processing technology will promote immediately the quality of design,ope

34、ration and control. Therefore optimization of material processing technology and material processing machine bymeans of realization of virtual simulation of processing procedure through quasi- reality design and concurre

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