1, introductive punch figuration is the metallic treatment craft with a kind of long history, as the ceaseless progress of industrial standard, punch technology and equipment are increasingly perfect, at present Japan has made the heavy-duty punch that gives level of 3000 tons of above, use at the treatment of large stamping workpiece. Current, still holding significant position in the industry punch treatment such as car, aviation, mould. Well-known, the major component part of the car is laminose stamping workpiece, early of each old car manufacturer begins abroad to design and be made what use the computer to emulate a technology to be used at directive product. And of the aggravate that competes as the market and environmental protection code come on stage in succession, auto industry is facing grim challenge, 3R strategy becomes the pursuit target of all car manufacturer: Shorten cycle of research and development, shorten charge of research and development and contractible and truckload weight (improve fuel efficiency) , and of 3R strategy carried out an application to technology of such as CAD/CAE/CAM to raise taller requirement. The development that punch numerical value emulates basically is relied on all sorts of board the emerge in large numbers of figuration software and progress, these CAE software can use the model that CAD builds to undertake design and process are emulated mostly, the development that is new product provides referenced basis. Current, the end that analysis of plank figuration CAE uses on industry is OK reduce is the following 3 main fields: (1) saves time: The inchoate judgement that whether can workpiece make; Shorten development cycle; Decrease debug a frequency; Answer what amend a tentative plan to the structure quickly; (2) cost saving: Reduce mould cost; Enhance dependability; (3) improves product quality: Preferred choose material; Can make complex part; Of all sorts of figuration parameter optimize. 2. Board the numeric imitate of development of imitate of figuration numerical value and figuration of plate of metal of algorithmic brief introduction only then at 20 centuries 60 time. The method that appears the earliest is finite calculus of finite differences, but this kind of method is confined to solve such as the axial symmetry problem such as globose drift bulging, to complex border conditioning is put in difficulty and fail to get applied extensively. Finite the application of yuan of method makes metallic figuration imitate achieves a breakthrough. Appeared in succession firm plasticity, play plasticity theory, and the figuration simulation that uses these theory to undertake, unit type is given priority to with velar unit and hypostatic unit, these research works are great drove board the academic development of figuration, but the application in actual production is far crudely. Actually, inside quite long period of time, board figuration is finite yuan of emulation research is much it is the level that keeps in experiment and test, the engineer that works to be engaged in punch, finite yuan copy is one is cost already really fluky tool, they aux would rather use method of a few geometry and simple mechanical method. The real progress that the occurrence of the software that is based on dynamic and explicit algorithm indicates figuration emulates a plank to apply actually, meanwhile, the software that is based on method of addition of static concealed type also develops further. To 1989, because of its powerful contact and be out of shape greatly, big translation / rotational processing capability, explicit and finite yuan algorithm has been in board figuration emulation domain wins wide application. Can say, in development process of two years, technology of plank figuration CAE has moved toward drawing office from the lab, produced main effect in mould design. The algorithmic component that when numerical value of figuration of header board material imitate uses is two kinds. Explicit law, concealed type law. Other still has way of one pace take shape. (1) explicit algorithm includes trends explicit with the static state explicit algorithm. The biggest advantage of dynamic and explicit algorithm is to have better stability. Additional, dynamic and explicit algorithm uses the center of kinetic equation to differ minute of format, need not beg solution tangent stiffness directly, do not need to undertake balancing iteration, computational rate is rapid, nonexistent also astringent controls a problem. This memory of algorithmic need also wants than concealed type algorithm little. Numeric computation process can undertake easily running paralell computational, to program is relatively simple also. On the other hand, it also has a few adverse sides. Explicit algorithm asks quality matrix is diagonally matrix, and calculate in unit class only as far as possible little speed per hour spends advantage ability to develop, often use method of cut down integral consequently, arouse sandglass mode easily, affect the computational precision of stress and meet an emergency. Dynamic and explicit law still has an important characteristic is: Differentiate correctly to the person that the emulation need of figuration process is used finite yuan of reseau and parameter of choice quality scale, speed and damp coefficient. The static state is explicit formula is inserted before the law is based on the balance equation group that leads a form and Euler, do not need iteration to seek solution. Because balance equation to get satisfaction in rate formally only, the result that reachs so is met slowly deviate is worth correctly. To reduce relevant error, must every pace uses very small increment, normally an emulation process needs to reach thousands of stage. Because do not need iteration, stability of this kind of method is so good, but efficiency is low. (2) algorithm of type of concealed of static state of concealed type algorithm also is a kind of method that solves metallic figuration problem. In algorithm of static concealed type, need to static balance equation iteration to seek solution inside each increment pace. Theoretic the increment pace in this algorithm is OK very big, but go up in real operation should get the limitation of the condition such as contact and attrition. Increase as unit numerary, computational time shows square almost second increase. Because need matrix to beg,go against and accurate integral, very tall to memory requirement. The adverse respect of concealed type algorithm still has convergent problem to get not easily settlement and should begin to wrinkle break firm when, in bifurcate matrix of point point stiffness appears bizarre. Have software of pace of big increment of type of concealed of a kind of static state additionally, also belong to algorithm of static concealed type, made certain improve, if the situation when big increment is used on conditioning of a few special contacts, bend to be not coupling to beg solution algorithm with drawing metabolic, of high accuracy get used to reseau to delimit cent is waited a moment oneself. These are special at metallic thin plate the feature of figuration appears very effective sometimes, but the in some way won't be so accurate. For example, it the process that accurate imitate is contacted and cannot break away from a contact, cannot forecast effectively corrugate break firm. (3) law of one pace take shape is planted in this the pace when one is being used only in algorithm, use method of linear meet an emergency normally assume, and oversight contacts attrition process, can calculate according to the configuration after figuration inside short time the measure that gives initiative preform. If combine CAD software and reseau,differentiate function, the initiative phase that law of this one party is designing provides very valuable information. Of course, the accuracy of the result normally very low, it is a kind of " seeks solution approximately essentially (Approximation Analysis) " . 3. Board the software that the application of figuration CAE software is based on method of one pace take shape got applied extensively in car manufacturer of Europe, its reason is this kind of method reaction is mixed quickly use convenient. Contrary, the company of Japan and United States thinks, the stress that through software of way of one pace take shape computation gets distributings not quite accurate, not be a kind of reliable actor chemical industry is provided. Current presence wears a kind to use the trend of dynamic and explicit algorithm, the adoption of dynamic in the imitate of BENCHMARK explicit algorithm is increasing. Algorithm of static concealed type is multi-purpose at certain hydraulic forming problem or combine computational spring back with explicit algorithm. Below a few circumstances, spring back and leftover stress condition are very fundamental, need to use concealed type algorithm in the imitate of process of whole plank figuration before, some board figuration analysed software to increase concealed type to analyse a function on original explicit basis now, accordingly, OK in these programs implementation board figuration arrives from punch the imitate of the whole process of spring back, analysis of the type that show hidden from view is accomplished without seam changeover, make thereby board figuration is emulated more convenient, efficient. Among them, eta/DYNAFORM is among them typical delegate. Eta/DYNAFORM is the major that American ETA company and LSTC company combination roll out board figuration software, devote oneself to to solve the most complex board figuration craft, use extensively at the world in factory of each big Motor Corporation, mould and university and research organization. Of Eta/DYNAFORM seek solution implement it is industry famous trends is explicit and finite yuan of analysis program: LS-DYNA, as explicit and finite yuan of originator of the program, LS-DYNA originallies in its some increased concealed type to analyse ability again on base of the explicit technology that seek solution formidably, enlarged the applied limits of the program further. To the computational error that cut and integral mode brings, LS-DYNA has a variety of sandglass to control a technology to overcome, in assure to analyse precision while, rose to beg solution efficiency. Eta company is in with the United States 3 big Motor Corporation (general, Ford, Kelaisile) the collaboration in collaboration of 20 years, accumulated those who abound board experience of figuration simulation engineering, the solidify in the program the expert experience that passes experiment test and verify in great quantities, gave out to different figuration technology best emulation parameter if: Quality scale parameter, speed and damp coefficient, reduced the demand of pair of person that use greatly, make mould and the tool that craft designs staff. The main characteristic of Eta/DYNAFORM is as follows: (1) the color that complete craft changes, yi Xueyi is used; (2) CAD interface of the standard (IGES/VDA) ; (3) advanced reseau builder, triangle, quadrangular reseau mixes and reseau is revised, clipping function; Of the reseau in figuration process suit oneself (Adaptive) differentiate function; (4) pull expediently delay muscle to create a function, DBFP forecast is pulled delay biceps; (5) plank falls makings dimension estimation implement, rise become a useful person rate; (6) pull quickly delay analytic function (need not build curve of punch and contact, load) ; (7) DFE - modular face designs module, generate by product geometry appearance control edge and sunken standard; (8) thickening spends board makings (solder board) figuration analysis; (9) substantial material library (135 kinds of metals and metalloid material) ; (10) the type that show hidden from view is not had seam changeover (spring back is analysed) ; (11) each are variable as a result (stress, meet an emergency, ply, energy) historical curve, cloud atlas and animation, cut take sectional show (wait like ply change) , FLD graph can show every unit figuration state to wait; (12) develop a function 2 times. The bottleneck that the car designs is automobile body enclothes a mould to design with production cycle. Cares main problem is by rip, decrease thin, cricoid skid wire, corrugate the workpiece defect that causes with spring back. The main show that the car assembles quality to differ is appearance of car whole geometry coordinate not accurately. The application of emulation software, decreased to try modular time greatly. For example, run quickly using before emulating, every mould needs to try a model roughly 3 arrive 4 times, now criterion 1 arrive 2 times to prevent to wrinkle with respect to enough with burst. Feng Tian Motor Corporation is in after introducing emulation system, the of 46% experiment in decreasing to the mould is designed and make a process works. The software that they use is Eta/DYNAFORM. Be in the United States and Europe, almost the main automobile body of 100% is enclothed pass emulation design, but there is 30% only roughly in Japan is application is emulated finish. This is the mould stylist as a result of Japan normally more it is to rely on experience to design a pattern. Numerical value emulates the ability when using new material new model only to consider as indispensible. 4. Board the future of figuration CAE develops way (the accuracy that the accuracy that L) raises an analysis analyses to continue to rise, this compose equation with need development and new application, destroy criterion and attrition model, especially this compose model to certain new material, still need much experimental data for this. In addition, must raise spring back and accuracy of leftover stress calculative. (The capacity that 2) increases an analysis is designed in the mould as emulation technology medium application increases ceaselessly, the figuration case that need has analytic is more and more complex also, also raised taller and taller requirement to emulating technical ability. The numerical value henceforth emulates the figuration that can analyse rigid standard condition to fall not only, and can analyse mould itself be out of shape (at present Eta/DYNAFORM can come true) , can rise to wrinkle in what contact an area so calculate a level. (3) is had optimize the figuration imitate with current capacity to basically still be used will replace actual mould to debug a process as fictitious experiment, cannot use turn a tool as actor. Susceptibility is used to analyse the method that implementation multi-parameter optimizes on maths of have the aid of, can undertake optimizing an analysis to plank figuration, receive first-rate plank form, control edge power, the figuration parameter such as drawing muscle position. (4) is finite of yuan of imitate and CAD environment two-way and built-in it is an inevitable trend. CNC Milling
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