Flying mechanism makes the application of material of alloy of the titanium in course of study

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While fuel price rises, aviation traffic is presenting high increase rate however. Tall fuel price makes the weight that reduces a plane, the abidance that brought about titanium alloy material from this grows. Accordingly, should seek the efficient treatment technology of titanium alloy material. Current, in aviation industry, basically be to pass those who reduce plane weight to reduce fuel further to use up. Because aerodynamics and drive design the latent capacity of the respect,already was dug almost. The A320 series aircraft that puts in the market in 80 time through airbus group company undertakes comparative with A350-XWB series aircraft, showed material uses what the change that make is helpful for plane weight to reduce (graph 1) . Further development composite material makes for example empty guest 787 dream plane can make A350-XWB series plane and Boeing light clever airframe. Get much CFK(carbon fiber gently to increase with weight especially plastic) with will replace aluminium alloy data. Graph 1 it is with the airbus exemple, the use of next generation plane material is formed. As the grow in quantity that carbon fiber composite material uses, the use of titanium and titanium alloy also subsequently ceaseless addition. Apply at the titanium alloy of plane airframe, 90% it is Ti-6Al-4V alloy. The titanium alloy that becomes more and more commonly used in this industry with its density (4.

43/cm3) celebrated to the good proportion of intensity. Aluminium alloy uses the place in forming to the share that hold is developed as the every time of new aircraft and be reduced in material. If possible sentence, it is by what become apparently so gently that much carbon fiber composite material makes the part replaces aluminium alloy part. When composite material of use carbon fiber has link with aluminium alloy, be worth the voltage with electrochemistry in view of the hot coefficient of expansion that differs each other, different intensity, should consider those who contact place to corrode, accordingly, to such join need lays insulation layer. To titanium and titanium alloy, because its are in with carbon fiber composite material,heat conduction and the intensity with the consistency of performance side, high electric conduction are mixed 0.

The potential of 2V, won't appear thereby afore-mentioned such problem (graph 2) . Graph 2 combine as material, carbon fiber composite material (CFK) be the same as carbon fiber composite material with aluminium alloy (CFK) the titanium that challenges a tradition with the comparison of titanium alloy machines a basis already bad news can the titanium with complex process and titanium alloy are made, typical titanium material machines craft (cast, forging and cutting is machined) club of the goods that it is make friends, garden expects or free forging provides further treatment. The treatment that the different point of these craft has stuff is temperature, accessible the volume that processes exterior quality, component and weight of work semifinished product are right the rate of workpiece product grammage (Buy-to-Fly-Verhältnis---Raw material weight is divided with component part weight) . When casting titanium, for example, according to equipment the condition in casting a process should adopt special precautionary measures ahead of schedule. Titanium falls in melt condition and hydrogen, oxygen and nitrogen have affinity, because this increased reaction capacity. Fusion and cast pure titanium and titanium alloy, below inert gase or vacuum condition only ability undertakes, the high melting point that besides makes an appointment with 1700 ℃ also makes of titanium cast increased difficulty. Inferior thermal conductance makes pouring and large component part becomes have challenge sex. And it is difficult that low cooling rate made make careful, flawless structure increase. Accordingly, the titanium data that can be used at undertaking constructional casts component part or semi-manufactured goods cast, producing such component part currently its possibility is finite. Current, weight amounts to 300 kilograms, edge most be as long as 1.

5 meters titanium alloy component, the mass that employs craft of casting of essence of life to be able to make manufacturer according to the plane asks to undertake production. Large to production with complex component part, although have very good overall material utilization factor,nicety is cast, but remain cannot replace cutting treatment. Besides, even if the outline of component part is close to finished product, through the titanium material that casts subtly component part must want to have cutting precision work. The other data on the side of the response division that produces when cast must want to be excised, so that acquire the character of requirement of function face place. 1 it is the forging that weight amounts to 550kg. 2 it is prior operation 3 it is rough machining 4 it is finish machining, component part weighs 25kg. Nextpage forgings to undertake (another kind of titanium machines craft) , it is better to used the data below higher temperature circumstance be out of shape function. But, even if be out of shape the case with higher temperature, according to the function of workpiece material, if be out of shape mediumly,speed is possible. In addition, when undertaking forginging below circumstance of standard atmosphere pressure, hydrogen of Lv of take an examination is fragile because the oxygen of material diffuses,consider make of brim layer hardness rise. Forging then after working procedure, undertake anneal to workpiece with eliminating stress is mixed undertake be cleaninged seriously to workpiece surface. After forginging then, often should undertake to forging farther turning or milling are machined. Accordingly, forging, also include to cast, the cutting treatment of titanium material cannot be replaced. Titanium material component basically has club of lump blank, garden in the semifinished product before cutting is machined makings or board makings. Graph the 3 doorcase that make with titanium, the rate to workpiece product grammage is weight of work semifinished product 22, be equivalent to material excision rate achieving 95% . Final workpiece outline is to pass cutting treatment to come true. When cutting machines titanium and titanium alloy, the challenge is its inferior stretch model quantity, higher intensity cost and inferior thermal conductance above all. Accordingly, can mix with greater cutting power only in inferior feed and inferior cutting speed (compare with cutting aluminium alloy) undertake to titanium cutting is machined below the circumstance. This brings about particularly little unit time material to excise a quantity, this and treatment aluminium alloy want quite 15 times smaller. Lesser unit time stuff excises a quantity, add again relatively the rate with higher to workpiece product grammage volume of work semifinished product brought about too long process time (graph 3) . As a result of inferior thermal conductance, because this is on cutting area and cutting edge,the temperature of generation is as high as 850 ℃ (graph 4) . Graph when alloy of 4 treatment titanium, the heat on cutting edge is accumulative, with the function of Ti-6AL-4V etc material. This function characteristic, promoted cutting tool material diffuse process (if diffuse,wear away, interpret is noted) with felt, make cutting tool generation larger wear away, also make cost of titanium material treatment high. And when cutting aluminium alloy, the process heat of 75% is taken away through cutting bits, when cutting titanium alloy, cannot produce the temperature adjusting control of itself. Here, the process of 25% is only hot by the eduction that cut bits. The data of cutting tool of coating hard alloy that uses at present to avoid produces overheat on cutting edge, cooling adjusting control makes central task. Use water radical emulsion to undertake cool and lubricating to cutting. Direct eject reachs the cooling channel that cooling fluid carries cutting tool interior with higher flow and higher pressure on cutting edge. Engineering of production of Darmstadt industry university and machine tool institute (PTW) the research that has makes clear, dinkum ester - oil is the substitute with water radical very good emulsion. Dinkum ester - oil although cooling power is inferior, but, what comparative to the lubricant effect of cutting edge is good, can avoid critical temperature in cutting process from this. In addition, use ester oil still makes cutting tool rose durability and allow to use measure such higher technology parameter to can raise unit time stuff to excise. When the machine tool that in the design cutting titanium alloy uses, must want to consider appropriate high-pressured cubage pump. In addition, as a result of greater cutting power, have special demand to main shaft, because give priority to an axis must can call tall torsion at any time, there is very good damp property even while this should have tall stiffness to perfect a machine tool, so that can restrain harmful cutting vibration. For example Luo Kexi gets · Martin company (Lockheed Martin Corporation) when milling titanium material the rate to workpiece product grammage is weight of its work semifinished product 11. This is meant, the material with its much 90 % is in the semifinished product of component part should be excised when cutting. If the price of 1 kilogram Ti-6AL-4V titanium alloy is 45 euro about, showed inferior to realizing cost treatment process respect still is having tremendous latent capacity. The new approach cost that titanium alloy machines is the impetus that optimizes titanium treatment, the material excision with inferior time of the unit when the cutting tool life with the inferior cutting tool when basically depending on pressing conventional treatment, cutting is machined is measured and exterior quality and be being cast and forging the decides harder craft parameter in the process. Use the technology that has cost effectiveness to replace a tradition to machine craft, these craft can be have the aid of at using laser or the accumulation of electromagnetism induction and titanium alloy component shapes manufacturing technology. Laser is assisted and electromagnetism induction is additional milling treatment is OK the category of classify hot cutting or concept of high temperature cutting, it is the limits that belongs to mixture treatment craft (graph 5) . Craft of two kinds of mixture treatment stands by the limits of cutting area to undertake local heating to workpiece through guiding heat energy, and the change that makes material function generation beneficial. As a result of temperature rise, quantity of the intensity of Ti-6AL-4V titanium alloy, stretch model and tendency of sclerosis of meet an emergency drop, the numerical value that drops when material temperature achieves 500 ℃ is amounted to 50% . Graph 5 use stimulate beam of light and electromagnetism response additional titanium alloy mixes treatment to cutting process, this is meant, the material that wins a same unit time excises a quantity, must want to produce lesser cutting power. And, can use taller craft parameter. Can come true 3 times taller than groovy cutting unit time stuff excises a quantity. No less, use laser additional cutting craft can achieve higher feed rate, obtain the stuff with unit more expensive time to excise quantity and longer cutting tool life from this. When rough machining, charge can be saved 80% , cutting force drops 40% , cutting tool life can get rising apparently. When undertaking be cuttinged eagerly to laser of have the aid of, the challenge that its face is besides should adjust outside laser focal length and power, still existing to stimulate beam of light to be in apparently reflex mixes workpiece to conduct pair of work through heat all round area can accuse harder heat. Auxiliary cutting and laser assist electromagnetism induction change model of plan lie differently the means at achieving heat energy. When laser assists milling, heat energy can achieve the appearance of workpiece only. Heat the limits that is located in workpiece material surface to fall can rely on heat to conduct only will achieve, this makes milling treatment restricts the deepness that making an appointment with 1mm in axial. By project of Darmstadt industry university and machine tool institute (PTW) the electromagnetism induction that place pays close attention to closely assists cutting technology program, with laser auxiliary cutting differs, its adopt the change of inductor frequency, can change the deepness that heat permeates. Reduce the frequency of alternating voltage, mean raised heat to permeate deepness. To the electromagnetism induction device of a 60kW, through using the frequency of 16kHz, hot osmosis deepness can achieve 15mm. This heating cubage can reach the temperature of 500 ℃ about, can undertake cutting directly next. Use this kind of technology, just can increase the excision amount of unit time stuff significantly when rough machining. CNC Milling CNC Machining