Metallic cutting is out of shape of the process finite yuan of emulation pre-test

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Metallic cutting treatment is one of treatment methods with a kind of wide application, it is to use stronger than workpiece cutting tool to excise a metal to obtain place to require a process of appearance, dimension and requirement of exterior surface roughness in workpiece surface. The essence that cutting machines is workpiece material in cutting tool cut extruding action to fall, be out of shape through flexibility, plasticity is out of shape tear off finally, the redundant metallic layer on workpiece work surface and workpiece noumenon depart generation cuts bits and fashion the process that the surface already machined on workpiece. Metallic cutting is out of shape the process is very complex, influencing factor is more also, the research of metallic cutting mechanism is the stress that domestic and international scholar studies and difficulty all the time, but the reason of respect of technology of be confined to, be based on all sorts of experiments and the research in the past basically has, wait for a reason as a result of cost technology measure, restricted cutting to be out of shape the research of the process gains ground with rise, but the occurrence of new material is to emerge in endlessly truly, the cutting processability that how knows new material seasonable and deeply can be urgent need people pays close attention to. In recent years, finite yuan the technology is out of shape in cutting the research of the respect has begun trend application. Use finite yuan the technology has experiment cost inferior, acquisition data is complete the characteristic such as diversity, and suffer fully inside course of study the personage's attention. The method of metabolic of research metal cutting that cutting is out of shape the tradition of the process analyses methodological discussion tradition basically is be based on all sorts of experiment methods and undertake, common method has: Flank is out of shape observation law, high speed photographs law, fast fall lens of report of law of photography of stereo of knife law, online transient state, scanning is microscopical a variety of methods such as law of trial of observation law, smooth flexibility and smooth plasticity. Additional, still have all sorts of methods that measure cutting force and cutting temperature to wait. Because the working requirement of metallic cutting is very abominable, of physical process dog observation is very difficult, and observation equipment material resources of long, manpower uses up cycle of costly, test big, integrated cost is very high, make its the result that all sorts of experiment methods analyse often not quite comprehensive, if flank is out of shape,observation law is through observing data side is artificial the petty pane of scale is out of shape will figure of the metal be out of shape. Although law of high speed photography can observe what actual cutting rate falls the sword to be out of shape of the area be out of shape circumstance, but cost is higher. Fall quickly knife law falls the speed of the knife is out of shape to cutting the accuracy of area information has certain effect, and the specimen of its cutting area wants specimen of make it metallographic to have observation. Law of photography of stereo of online transient state and scanning report lens show microcosmic examine law to all have the drawback with test very costly equipment. Above tries proved recipe way a few kinds, of surface of the stress that often cannot measure area of quantitative change form, meet an emergency, cutting tool pressure, temperature reachs his to distributing the rule. Although smooth flexibility and law of smooth plasticity trial can describe the information such as the stress meet an emergency of cutting area, cannot reflect the pattern that material flows however. The method of above discussion basically is to be centered at cutting to be out of shape, namely the data flow rule in cutting process and its physics ration are described. In fact, cutting is out of shape the process is returned wait with cutting force and cutting temperature have reach its close connection, be out of shape cutting cutting apart to study respectively with cutting force and heat in metal cutting cannot be taken, should undertake study as a whole. The research of conventional cutting force basically is to pass the method of the experiment to get experience formula as a result, offer next use actually. To certain and actual condition, if deviate experiments condition, put likely in the error, imponderable even. The measurement of cutting force basically has resistor meet an emergency piece type measures power appearance measures power instrument with the type that suppress report two kinds, these measurement unit are common all relatively precious. What the measurement of cutting temperature basically uses is natural thermocouple and artificial thermocouple law, former the average temperature that just measures cutting area, but the distributinging pattern that cannot reflect a temperature well and truly. And artificial thermocouple is to be used at measuring cutting area the temperature some, but the temperature field that should acquire whole cutting area is very difficult still however. Additional, if the law mixes radiation thermometer the measurement technique such as law of heat quick dye because facility cost is higher and the application that restricted him. By on be narrated knowable, the traditional research technique that is based on an experiment has more difficulty, and finite element law is in go up somehow can overcome above a few defect, because this causes the attention of investigator gradually. Cutting is out of shape of the process finite yuan of emulation analysis is finite the research that assists emulation technology to machine a process to cutting basically centers yuan of computer at 2 respects, it is relevant the development of emulation software, the physics that is the cutting treatment process that is based on special software to undertake next is emulated. Former and general undertake study by professional personage, existing relevant software has Third WaveSystems company " Advant Edge " , the DEFORM software of company of Scientific Forming Technologies, still have a few current software additionally, wait like ABAQUS, ANSYS. Latter notes the research that overweight uses actually, the article basically discusses latter research result. Undertake introductory through an example below. The graph shows the model that is an orthogonal cutting 1 times, cutting speed V=250m/min, cut ply Ac=0.

4mm, workpiece width W=2mm, ° of 0=5 of γ of the horn before cutting tool, α 0=5 ° , rn=0 of radius of cutting blade blunt circle.

1mm, cutting tool - the coefficient of friction between workpiece is 0.

6, hot conductivity is 40, cutting tool surface from outside to inside besmear respectively Fu the TiN with 10 μ thick M and Al2O3 coating, WC of material of cutting tool noumenon hard alloy, workpiece material AISI-1045 (be equivalent to 45# steel) , environmental temperature takes 20 ℃ . Process of metallic cutting treatment behaves those who be a metal to be out of shape bigger, to model of this kind of cutting finite yuan emulate, in finite yuan reseau distortion arrives after certain level, system must can differentiate automatically again reseau, the graph shows the reseau case of the reseau before be cutting respectively and cutting knife pace 2 times. Graph 2 (A) it is the reseau circumstance before treatment, can see treatment section is secretter. Graph 2 (B) it is cutting weighs differentiating circumstance automatically to the reseau when 500 paces. Actually, in emulation process, the system is met according to reseau distortion circumstance seasonable and automatic redraw divides reseau. Of Nextpage cutting process finite yuan emulate, its turn out is relatively rich, the method that includes appearance of flow of rate of stress, meet an emergency, meet an emergency, metal and rate of going from place to place, cutting tool the temperature field to area of pressure, cutting distributings, cutting force chart, cutting tool wears away, and can be out of shape like traditional side imitate gives metallic flow rule like observation law. Additional, use these result graphic representation, still can measure a relevant cutting to be out of shape descriptive parameter, if cut horny φ and cutting ply to be out of shape coefficient ξ A, the analysis can use the form such as cloud atlas, contour map and animation to express as a result, can return at any time, animation process is OK weak condition or demonstrate continuously. All these visible results, cutting are out of shape the description of the process is more traditional trial law had huge to rise, a few are listed to emulate below offer reference as a result to the analysis when 500 paces. Graph 3 be out of shape for what cutting machines a process meet an emergency pursues, can see in the graph cutting is out of shape the process is out of shape 3 times not only the circumstance of meet an emergency of the area, and the case of meet an emergency that still can see the surface after cutting is machined remains. The 2nd is out of shape the area is caused strain in the graph is the greatest, it is the first meet an emergency that is out of shape the area arises next, the 3rd meet an emergency that is out of shape the area arises is the smallest. Graph 4 pursue for cutting stress, can see in the first be out of shape of the area be out of shape stress is the greatest, and be out of shape stress basically happens around point of a knife pass an imperial examination is out of shape area. Graph 5 (A) be shown pursue for rate of cutting metabolic meet an emergency, performance of speed of meet an emergency is an edge the first be out of shape of the area cut rate of meet an emergency the biggest, use this result to be able to divide separate out to cut corner φ , specific arrive to pursue this duplicate in AutoCAD, draw goes out horizontal and cut a line to be able to be measured piece cut corner, if pursue 5 (B) be shown, this those who measure cut horny φ to be 35 ° . Of course, use cutting metabolic to emulate a result, the cutting ply A C that goes up through measuring A Ch of the ply that cut bits and workpiece (before narrate foregone) , can calculate give ply to be out of shape coefficient ξ A=a Ch /ac =0.

64/0.

4=1.

6. If pursue,measure an outcome 5 (C) be shown. Graph 6 (A) the data flow rate that is cutting process is local enlarge graph, this graph can see the way that material flows not only, and still can use cloud chart (graph 6 (B) ) or contour map (graph 6 (C) ) wait for visible means observation to go out everywhere the athletic speed that material flows. Graph 7 (A) the cutting temperature picture that shows to use the form of cloud atlas, it is temperature field graph character actually. Also can express with contour map, if pursue 7 (B) be shown. If cutting area local enlarge, what can look is clearer, if pursue 7 (C) be shown. Can see point of a knife of highest temperature deviate from inside the graph, and the temperature of face of the knife before cutting the cutting tool of temperature prep above on bits. Highest temperature is this kind of circumstance as a result of,be of temperature elevatory be out of shape with cutting not only about, and return and cut bits and before the attrition of knife face is concerned. Nextpage pursues 8 it is cutting tool surface graph of enlarge of pressure contour line, can see from face of the knife after point of a knife is forward particular area got bigger pressure, knife face gets force area before more. The biggest pressure is in about 0.

8MPa above. The graph is shown 9 times is graph of imitate of cutting reseau flow (310 paces) , its simulative result special the result that is out of shape like traditional side observation law gets. The graph is shown 10 times is cutting process in advocate cutting force and graph of cutting time change, the earlier cutting strength that can see cutting tool cuts workpiece material adds very fast, tend gradually next stable. Here still can show the volume of cutting force directly, power of the cutting after can seeing stable cutting is maintained basically control in 750~850N. Above listed the outcome of a few kinds of analysises that a few kinds of cutting are out of shape be interested relatively in research only, can see, finite the result of yuan of emulation postposition processing is relatively rich and complete, have huge help to knowing cutting deeply to be out of shape. Treatment of last word cutting is a complex cutting is out of shape process, working requirement is very abominable, traditional research technique basically is based on experiment research, physical process dogs observation is difficult, and experiment cost is very high, if want to obtain more test data, need to use more experiment method, do more test, such ability make people right the cutting function of all sorts of material has deeper knowledge. However, apply finite yuan of analysis, have the aid of wait at computer technology can announce with inferior cost cutting machines a process, and all sorts of relatively rich data are obtained in shorter time internal energy, this has huge help to actual production. Of course, as a result of finite yuan of practice that the technology uses at cutting to machine is not long, still a lot of technology issues are worth to discuss. Additional, finite yuan of emulated result and actual condition still have certain difference, analyse its reason, the author thinks to have at 2 o'clock, it is the mathematical model oversight when software weaves a few minor factors; 2 be the setting of relevant parameter when emulating and use software person intellectual level and practice experience are concerned, if setting parameter deviate is more,make necessarily emulation result has certain difference. Accordingly, eye comes round to say, will limited test and more finite yuan of emulation photograph union, it is a kind of practical research technique. CNC Milling CNC Machining