Come about 50 years, aircraft manufacturer increases in use fiber all the time plastic (Fiber-Reinforced Plastic, FRP) material. Be opposite as the industry the knowledge of FRP material good point is more and more intimate, the utilization rate of this kind of material also rises steadily in year after year. Although be in original when FRP material wants than the cost of traditional material a few taller, but its are in efficiency, maintain and the advantage that fuel saves accrual to go up is very clear, accordingly these advantages just can be made up for in the plane the inferior position with initiative investment higher cost. Graph electron microscope of 1 scanning type (SEM) the surface of fiber-optic Laser Cutting below, show slight exterior heat to damage. Carbon fiber increases plastic (CFRP) increase with fibre glass plastic (GFRP) by manacle the carbon fiber in aggregate colophony or composition of fibre glass base, bring the character of a lot of contented need thereby, the most remarkable is high strenth weight is compared, still have tall hardness, small hot coefficient of expansion and exceedingly good corrosion resistance. Graph the 2 fiber that use fiber-optic laser cut, can see damage without heat. Use lighter FRP material to make an aircraft, the fuel cost of millions of dollars can be saved every year on the flight. E.g. , boeing 787 " dreamy plane " economic during service life aircraft upkeep cost is about 30 million to 40 million dollar between. The advantage of FRP material has a lot of, but well-known is this kind of material is machined very hard. Traditional treatment method, for instance mechanical milling is mixed bore, can cause splintery, heat to damage, statified, fiber pulls out and to the tool wear away badly. Latter, people studies use water fixes cut, but still can cause fiber statified the practical limitation with etc. E.g. , should machining initiative place is not to be when the brim of material, get an oriented bore with respect to need. The data that is not contact as a kind moves except craft, laser beam machining can offer the program that solves afore-mentioned problems. However, all the time since, in this kind of application, the interaction between laser and material still did not get understanding extensively. Be aimed at this problem, england of combination of JK Lasers company is Liverpudlian John rub Er university (John Moores University) began research together. Understand the interaction between laser and material more to let researcher, the laser source that used character of two kinds of beam of light to differ in research will machine. Use the Nd:Y that contains bore nozzleAG laser JK300D (with fiber-optic transmit, have power of high peak value) will undertake percussion drill aperture experiments. Use the 200 watt that contain cut nozzle JK200FL of laser of Chan Moguang fine undertakes cut experiments. Use the JK200FL that deserves to have scanning head to undertake perforation and milling experiment. The main factor that the interaction influence FRP of laser and material machines depends on carbon fiber or fibre glass and polymer base photograph are compared, characteristic difference is great. What the laser power that vaporization fiber asks wants to compare vaporization polymer is a lot of taller. When handling CFRP, the reaction difference of thing is the most apparent. Vaporization polymer asks merely a few heat energy, and the heat conduction ability of carbon fiber is first-rate, this also is meant before cut fiber, much energy has been conducted. Accordingly, to high quality laser beam machining, must the input of quantity of heat that special attention manages material. Using Nd:YIn the process that AG laser has pounding bore, used two kinds of different auxiliary gas: Nitrogen and carbon dioxide. The result shows, use auxiliary gas has bigger effect to the quality of aperture. When use nitrogen serves as auxiliary gas, example apparently the layer after leaving polymer base pyrolysis. And when use carbon dioxide serves as auxiliary gas, the exterior quality of the FRP after processing should rise a lot of. Appear because the cool mass of carbon dioxide is close friends,such result is a few. When using fiber-optic laser to have cut to FRP material, brought heat is damaged very few. Because the facula size of laser is very small,this is. Graph 1 and 2 those who show is fiber-optic laser cut the surface and the SEM image that bring heat to damage. From what can see heat damages composite material be been in by limitation clearly on image alone one goes up. These results are versed in be very advantageous for course of study to aviation and spaceflight. Because the much of material did not suffer effect of laser beam machining, because of this composite material still very firm with stability. Graph 3 those who show is mechanical the brim quality that cuts off generation is the same as photograph of fiber-optic Laser Cutting relative circumstance. On the example that cuts off in machinery, can see composite material highlights fiber for the most part, and smooth margin can see on the example of Laser Cutting. Graph 3 mechanical cut (Zun Tu, enlarge 500 times) with fiber-optic laser cut (right graph, enlarge 1200 times) brim cut quality is compared. Nextpage and the result that obtain in cut experiment are similar, result of laser milling test shows, the small facula dimension of fiber-optic laser is very advantageous to milling application. The fiber after laser is handled did not heat up harm trace, after SEM magnifies times higher, can see base material has slight fused mark only (graph 4 with the graph 5) . Test result confirmed use light the possibility that fine laser has milling to composite material of aviation and spaceflight. Graph surface of composite material of 4 laser small treatment, speed is 200 millimeter / second, auxiliary gas is air (Zun Tu is enlarge 80 times, right graph is enlarge 500 times) . Graph surface of composite material of 5 laser small treatment, speed is 250 millimeter / second, auxiliary gas is carbon dioxide (Zun Tu is enlarge 50 times, right graph is enlarge 500 times) . Still use fiber-optic laser JK200FL to drill the hole of 2 millimeter diameter in the annulus on FRP composite material likewise. Cut experiment makes clear, for the composite material that exceeds 1 millimeter to ply, try to handle composite material like treating a metal, its cut result does not make a person satisfactory. Because this needs largish cut to make,material can be broken away from, do not let base conglutinate be on new cut range. The strategy of this kind of design calls bore of laser helix shape. With use Nd:YThe Kongxiang that AG laser gets is compared, the heat of bore of laser helix shape is damaged should a few less, brim quality of the surface looks better. The flash back quantity of coping surface has a few micron only. The result that fiber-optic laser bore experiments shows, in deserving to have the laser beam machining of scanning head, its machine the structure of open mode geometry of speed and aperture to close suitably, can reduce the harm of material of base of surface of FRP composite material. Graph the 6 image that those who show is the GFRP composite material after passing bore of laser helix shape. Graph the summary of bore of laser helix shape that fine laser machines 6 use light uses light the Nd:Y of the power of high peak value that fine transmitsThe test result of fiber-optic laser demonstrates AG laser and pattern of 200 made of baked clay sheet, laser can offer the treatment quality that traditional technique measure cannot offer. Heat management is the key that processes FRP composite material. Be like carbon dioxide through using such auxiliary gas, can great the harm that reduces laser light beam to cause. Use the experiment of fiber-optic laser to make clear, small facula dimension and the careful and directional hot input that bring subsequently are very advantageous to processing FRP composite material. The fiber-optic laser that owns dimension of quality of tall beam of light, small facula and optional scanning system is proved special apply to treatment these material. Test result still makes clear, bore of laser helix shape reachs car domain laser beam machining to apply a lieutenant general to act important role in the aerospace henceforth. The manager of global big client that article author Dr. Mohammed Naeemm is company of laser of the JK below GSI group division, his email address is Mnaeem@gsig. Com. CNC Milling
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