Colophony radical because composite material is had compare Gao Bijiang, high model, high temperature resistant, anti-corrosive, be able to bear or endure sex of damping of fatigue, damp good, function can design security of good, damaged wait for an advantage, already developed the basic material that makes aerospace structure. At the same time the disperse sex of the advanced sex of composite material and its quality and high cost coexist, in applying actually, although passed research and experiment to make sound technology, but blemish of possible still in the production process of composite material structural member generation, pose quality problem, bring about whole structural member even discard as useless, cause significant pecuniary loss. Accordingly the nondestructive of composite material detects technical emerge as the times require, the nondestructive of inchoate and complex material detects the technique is main the nondestructive of metal of continue to use detects, but the nondestructive that discovers its cannot solve composite material completely detects problem, 20 centuries after 80 time, a lot of nondestructive that get used to composite material characteristic detect new technology, new method is born in succession. First we will see colophony radical composite material is common blemish has those. Statified: Matrix, fiber, grind a heat to coefficient of expansion does not match or store time grows too; Be mingled with: Operate error or operate beforehand undeserved; Take off stick: Binder chooses undeserved or solidify is not complete; Hole: The volatilization of impurity of solvent, small element, vacuum control is undeserved; Concussion, bump injury: The tool falls off or other outside object collision is caused; Fiber music bends: Dip expects itself has drawback or operate beforehand undeserved; Fiber ruptures: Beforehand quality of the fiber in dip makings is bad;

China unsaturated polyester resin (UPR)

Is composite material common can these blemish use blemish do those composite material nondestructive detect technology? 1, ray detects technical ray detects technology (Radiographic Testing, namely RT) is to use ray (X ray, γray, neutron ray) the character of the absorption when crossing an object and scattering, detect its interior structure is discontinuous sexual technology. Agree with: The bulk such as hole, be mingled with blemish detects, at ray to parallel the crackle of penetrable direction has those who had compared to detect the effect, gather with fiber to the peculiar colophony in composite material it is certain to wait for blemish to also have detect ability, it is when lay up amount is less, still can discover the fiber inside lay up bends wait for blemish. As a result of statified the medium on penetrable to ray direction does not have blemish to be affected apparently, because this is statified,blemish is in resemble going up and not apparent. Same reason, ray detects the technology is right parallel the crackle at material surface is not sensitive also. Ray detects the technology divides again for 3 following categories: Ray takes a picture to detect in all ray in the technology, film ray takes a picture technical development is early, and digital type ray is become in real time resemble detecting technical criterion development is rapid. Take a picture with film technical photograph is compared, digital type ray is become into what resemble a technology take a picture like quality and film the technology comparatives, the real time sex that detecting, efficiency, economy and wait for a respect easily to having incomparable advantage with the gender, got rapid development consequently. Current, the real time that has certain intelligence to identify ability is become resemble detecting what the technology has applied at composite material product is online detect, the work that can attend to assembly line undertakes real time detects quickly, become ensure of product percent of pass important detect method. Photography of analyse of industrial CT layer also calls computer fault to scan picture (ComputedTomography, namely CT) , this technology is the interior that uses X ray to explore an object, through determining the attenuation coefficient of ray, use mathematical method, via computer processing, the 2 safeguard that seek solution to give attenuation to fasten numerical value to go up in some section plane distributing matrix, change distributings for the gray scale on image picture, realize those who build section image to become thereby like the technology. Pass those who analyse the density inside fault face to distributing, can obtain composite material interior content of bulk of density uniformity, small hole and distributing the information that waits for a respect. Generally speaking, the contrast of CT photograph wants than the contrast of X sciagram low, but because removed issue of double image of overlay of different level image, actual readability is strong at X sciagram. Nevertheless CT becomes the matter that decided like the principle density is high to be able to be magnified on certain level, the dimension that this also brought about the scathing image such as statified, hole, crackle compares real measure slightly the blemish image with the small and high density such as fiber accumulation compares real measure slightly big peculiar phenomenon. As a whole, CT scanning is had into the technology that resemble below characteristic:The resolution between headroom and density resolution (normally < 0. 5%) tall trends detects limits (arrive again to composite material from air metallic stuff) ; is into tall like dimension precision; below the condition with penetrable sufficient energy, do not accept restriction of structure of test specimen geometry. Limitation expression is: Detect efficiency is low, detect cost is tall, bilateral transmission is become picture, do not agree with of planar and laminose component detect and the spot of large component part detects. It is OK like the technology to use CT to become detect effectively the blemish such as the hole in advanced composite material, be mingled with, crackle, the thickness that also can measure material interior distributings circumstance, wait like content of material uniformity, small hole. On industrial application, the United States is in on 80 time develop the century went out to be used at detecting the industrial CT equipment of housing of composite material of motor of rocket of large solid body, in using this technology at the nondestructive of structure of other composite material to detect gradually, our country also at going up century 90 time later period uses industrial CT technology successfully at C /C composite material, carbon / phenolic aldehyde composite material detect, solved a few decisive nondestructive to detect technical difficult problem, gained better economic benefits and social benefit. Compton back scattering is become resemble detecting technical Compton carries scattering on the back to become picture (CST) technology is a kind of new ray detects technology, it has odd side to be not a contact, detect sensitivity is fast and tall, three-dimensional into the characteristic that resemble, to low density material detect can obtain become than transmission like taller image contrast, special agree with the atomic number such as composite material is inferior the object of material. When by check object structure complex, or cannot undertake bilateral into when resembling detecting, CST technology showed distinct advantage. Current, CST technology had received wide application in foreign aerospace domain, in home, still be in advanced research phase. 2, supersonic detect technical ultrasonic is the sound wave that points to frequency 20kHz, the dimension photograph of its wavelengh and material interior blemish matchs. In material interior according to ultrasonic blemish area is mixed the position that the reflex of normal area, attenuation and syntonic difference will come to fix defect and size. Ultrasonic detects main component is pulse bounce technique, through transmission technique and baffle-board law, will choose to detect suitably according to different blemish method. Apply to: Ultrasonic can detect not only the statified, hole in composite material component, crackle and field trash, and orientaton of the density that judging material, density, fiber, music is bent, the change of the respect such as the character such as stretch model quantity, ply and geometrical appearance also has certain effect. To general the component part with the planar layer pressing plate with small and thin, simple structure and not large curvature, appropriate uses leach type baffle-board law; to small or a bit thick complex structural member, cannot use leach type baffle-board when the law, can use leach or bounce technique of gush water pulse and contact bounce technique of defer piece pulse; is mixed to large construction of the composite material component of type of production detect appropriate uses gush water through transmission technique or bounce technique of gush water pulse. Because composite material organizes a structure to have apparent anisotropy, and the disperse sex of function is bigger, consequently, the mechanism that produces limitation is complex and change is diversiform, the acoustical attenuation plus composite material component is big, the noise that causes from this and the letter a confusion of voices that blemish reflexes signal are compared low, differentiate not easily, appropriate method should be chosen when detecting. Specific applying: The component of large composite material such as aircraft spare parts, the complex structural member such as beehive bubble with filling, curved surface component, plywood of layer of airframe of Boeing plane composite material writtens guarantee the nondestructive of compose detects. Supersonic detect methodological cent detects for traditional ultrasonic method, exceed acoustic conductance wave to detect method, air coupling is supersonic detect technology, laser is supersonic detect technology, accuse blast supersonic detect technology. 3, infra-red heat wave detects the technology is infra-red hot wave nondestructive detects (Thermal Wave Testing) is used heat actively technology, the temperature difference that because different hot character is caused,becomes blemish of surface of self-recording like the system test specimen and base material through infra-red heat, decide then appearance of the substance that be measured and internal damage. Apply to: Should detect the method is special agree with detect composite material thin plate and metal are stuck receive a structure to be taken off mediumly stick, statified kind of area blemish, become especially spare parts or component cannot undertake supersonic C- scanning detects in water intrusion and figure of spare parts face makes supersonic detect infra-red heat wave also can be used to detect when it is more difficult to carry out method, method of infra-red heat wave can deepness of the storied in accurate and certain composite material, and this method has blame contact, real time, efficient, intuitionistic characteristic. 4, sound - supersonic detect technical reputation - supersonic (Acoustic-Ultrasonic) technology calls stress wave factor again (SWF) technology. Apply to: The subtle blemish that AU technology basically uses at detect and studying material is medium to distributing group reach its mechanical to the structure function (intensity or stiffness) integral influence, the integrality that belongs to material assesses a technology. Adopt tone - technology of scanning of supersonic amplitude C also can is opposite between composite material and metallic stuff stick abutment face to undertake detecting effectively, and overcame the weakness that accessibility of sensor of not tall, supersonic transmission technique needs definition of signal of supersonic reflex technology. 5, sound blasts off detect technical reputation blasts off detect technology (Acoustic Emission) is transmit undertakes the sound that produces through be to composite material or structure in to load process detect and be analysed, one kind when undertake evaluating to the integral quality standard of composite material component detects technology. Apply to: The development of the injury in reflecting composite material and destroy mode, cast component part bear the weight of eventually intensity, can decide the fragile area of component part quality truly. Acoustical emissive technology is to detect the very practical technology step of standard of quality of whole of composite material structure, use go to the lavatory simply, can testing material mechanical function while get material trends to be out of shape the valuable information in injuring a process. 6, eddy current detects technical backset detects technology (Eddy Current Testing) is the electromagnetism induction appearance that uses conductor, through measuring the method that the change that the induction measures has nondestructive detects. Apply to: Use at conductor, can use at carbon - carbon composite material and metal base of composite material detect. As a result of the existence of termination effect, this method detects in what border is in the result is bad, at the same time this technology needs to undertake contrast with standard sample, accordingly its application got restrict. 7, microwave detects technical microwave is the electromagnetic wave that shows frequency is 3000GHz of 300MHz ~ , it is the abbreviation of a finite frequency band in radio wave, it is cent metric wave, li metric wave, millimeter wave and inferior a general designation of millimeter wave. Microwave frequency is taller than general radio wave frequency, also call ” of “ UHF electromagnetic wave normally. Apply to: Microwave directivity is tall, penetrable in composite material ability strong, attenuation is small, agree with detect the stuff with older ply. Craze of medium hole, loose to the structure, matrix, statified mix stick wait for blemish to have taller sensitivity. Go up century 60 time, microwave detects of the blemish that the technology has used in housing of glass reinforced plastics of engine of large missile solid and in-house quality detect. Carry out a proof, the ply error that uses bounce technique to measure is less than 0. 125mm, use through transmission technique to be able to determine 0. The density of 02mg /cm3 changes. Cannot penetrate as a result of technology of microwave flaw detection conductor, because this detects this kind,the method applies very hard at overall detect. 8, the fluid permeates law fluid detect the law applies to the drawback that has open sex cut or injury merely, this kind of method is to use tailor-made bleeding agent to undertake coloring to blemish and injury, but the meeting in coloring process pollutes material, can increase on certain level repair difficulty, use at present less. 9, laser is holographic law laser is holographic inspection (Laser Holography) is laser hologram is applied integratedly with what interfere weights and measures technique. The basis of this kind of technology is object interior blemish is below outside force action, the object surface generation that makes its place corresponding and not identical minim displacement is poor all round its. The method that uses laser hologram next undertakes comparative, examine thereby the blemish that gives object interior. Law of proved recipe of this kind of check because costly, need flushs device develop, sensitive to environmental vibration be opposite with need to load of the content that be measured, because this limitted promotion ability, basically use in the lab at present. 10, the macroscopical blemish that range estimation law is surface of composite material of person eye observation, basically be exterior crackle and injury, the advantage depends on cost low, efficiency is tall, but have bigger factitious factor. Reference material: Composite material nondestructive detects method. Liu Huaixi,

Newsolar Conference
15-18 December

New York City