Treatment of material of a few kinds of advanced aviation of foreign uses cutting tool

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Aviation is industrial the characteristic of material is to ask quality is light, below high temperature and microtherm condition, taller than intensity, integral performance is good, chemical stability is good. For this, people developed a lot of new material. Can have aluminium alloy, titanium now as the metal of aviation material alloy and exceed heat-resisting alloy. Aviation has CFRP with composite material (carbon fiber composite material) etc. These material great majority are the material of difficult treatment. It is with advanced American Boeing aircraft exemple, 30 years already from former some 747 model plane, development arrives current 787 model, literary composition of data of its airframe share becomes: Begin wide used aluminium alloy falls by 81 ﹪ for 20 ﹪ , steel falls by 13 ﹪ for 5 ﹪ , and titanium alloy increases 15 ﹪ by 4 ﹪ , composite material increases 50 ﹪ substantially by 4 ﹪ . Same, of Europe newest the aluminium alloy that empty guest A350WB uses occupies 20 ﹪ only, steel occupies 7 ﹪ only, and titanium alloy is added to 14 ﹪ , composite material more be as high as 52 ﹪ . In the reaction engine, microtherm low pressure uses titanium alloy commonly partly, also the part uses composite material CFRP recently. Part of high temperature high pressure is multi-purpose nickel radical exceed heat-resisting alloy, be like Inconel718, hastelly, waspaloy, rene41. The titanium alloy that belongs to stuff of difficult treatment metal and exceed heat-resisting alloy, if difficult cutting degree cuts steel easily in order to contain sulfur to cut an index easily to be 100 plan, criterion austenite stainless steel is 45, the Ti-6Al-4V in titanium alloy is 26, inconel718 is 12, rene41 is in 5 the following, sex of knowable difficult cutting is ordinal increase with 2 times much ground. Titanium alloy and the characteristic titanium alloy that exceed heat-resisting alloy have the following fabricating characteristics: (1) the heat in metal cutting that generates in cutting process is tall, and thermal conductivity is poor (the 1/7 that is steel about, aluminous 1/16) , make temperature is centered in point of point of a knife thereby, often be as high as 1000 ℃ above, reason makes cutting tool is injured because of high fever easily. (2) amount of model of titanium alloy flexibility is small, after cutting gets power, flexibility restores, the attrition of face of knife of around of meeting aggravate cutting tool, raise cutting temperature further, quicken cutting tool to wear away, return easy vibration. (3) easy by treatment sclerosis, and oneself chemistry active is big, wait for reaction easily with the oxygen in air, make the surface hardens, of aggravate cutting tool wear away. (4) of titanium and heat-resisting alloy cut bits easy cohere to be on cutting tool, in treatment felt content is enforced by follow-up treatment when eliminate, can cause loss of cutting tool felt, lower cutting tool life. The titanium alloy that uses the most extensively is α - the Ti-6Al-4V of β photograph. Boeing 787 model the Ti-5Al-5V-5Mo-3Cr that used titanium alloy is β photograph, machine harder. Nickel radical exceeds the fabricating characteristics of heat-resisting alloy: Above all, its contain alloy composition rate much, alloying element and carbon form all sorts of carbide and complex carbide, these carbide not dissolve at alloy, distributing with extremely fine grain form dispersion however in crystal boundary, can aggrandizement crystal boundary, prevent the slippage below outside force action, make alloy shows exceed strong property. Next, bigger than intensity, want to machine nickel radical to exceed heat-resisting alloy, must do greater work, in order to produce more heat. And thermal conductivity is poor, make the quantity of heat that generates in cutting not easy eduction, let temperature achieve thereby taller. The characteristic of a lot of difficult treatment is in titanium alloy in exceeding heat-resisting alloy, behave more acutenessly, its machinery, felt, diffuse to wear away with oxidation more serious, because this exceeds heat-resisting alloy,compare titanium alloy more machine hard. Titanium alloy and exceed heat-resisting alloy treatment to be development titanium alloy and the outstanding cutting tool that exceed heat-resisting alloy treatment to use with cutting tool, should study improvement affects cutting force, hot each factor, improve cooling result, make cutting force, heat drops, heat is accelerated derive; Raise machining complex departmental cent is rigid, in order to restrain vibration; Reduce cohere, discharge bits to wait quickly. If these principles where fulfil on the cutting tool, specific design that establishs milling cutter, face milling cutter, broach, select material and cutting condition set, mix with foreign SIMTEK below SGS company is exemple, undertake demonstrative. Introduce the new material that they develop for this and coating first, german SIMTEK company developed turning to cut the GT45 of chamfer of inside and outside, FT45, HT45 and GX79, use at the GT42 of mill chamfer and GT79. Can use at titanium alloy already, also can use at exceeding the treatment of heat-resisting alloy. The special coating Ti-NAMITE-A(AlTiN) that American SGS company develops, as a result of its special deposit technology and constituent structure, treatment titanium alloy and very good result was obtained when exceeding heat-resisting alloy. The coating of another kind of Ti-NAMITE-B(TiB2) that SGS company develops, hardness achieved HV4000, can use at machining aluminum-silicon alloy. The data that they use at making cutting tool matrix is to exceed atomic hard alloy, the special coating that tries to be developed alone, those who achieved the integrated and mechanical performance such as hardness and tenacity is farther rise. There are a lot of chamfers to machine the grooving knife with need exceedingly good performance characteristics on aviation engine spare parts (see a picture 1) . Groovy treatment gets power as a result of 3, cutting resistance is great, heat in metal cutting is tall, medicinal powder the condition such as bits of hot, cooling, platoon and tigidity is poor. German SIMTEK company developed a variety of V clamp of form piece fixed position is modular structure, the installation that improved bit greatly is rigid. Besides can machine all sorts of chamfer, change other knife head to still can machine all sorts of aperture, and the whorl of different level. Whole of spare parts of this pair of aviation is made, assure to be able to machine an a lot of surfaces in be installed, the spare parts that the demand assures mutual position precision is high is very advantageous. In the light of include titanium alloy and exceed heat-resisting alloy inside boat aviation accident processes data, the material of high grade razor blade of SIMTEK company is when turning grooving, speed of titanium alloy cutting is 60 ~ 110 meters / cent, and the cutting speed of alloy of nickel radical heat-resisting is 30 ~ 50 meters / cent. The treatment that turning grooving place differs with bit correspondence has what suit severally to break bits chamfer. Graph knife and the engine spare parts that often machine are opposite the of all kinds grooving of 1 SIMTEK to establish milling cutter commonly, of tooth enter, exiting is periodic, this may form ruinous simple harmonic vibration, keep abreast of and cause the resonance of whole cutting tool to injure. The patent characteristic design of American SGS company makes his much the fund stands milling cutter from inside restraining treatment greatly brace up quiver. Like Z-CARB-AP model not only have differ alveolar helix angle, alveolar the span between also differs, the corner structure before what still have patent is alterable, will restrain vibration from many sided, decrease and stabilize cutting force, make machine life of quality, efficiency, cutting tool to wait to all be able to rise (see a picture 2) . Graph 2 in all indicating functions, all be assured by the geometrical structure that passes special design. This milling cutter is 91 ~ in the speed when cutting titanium alloy 104 meters / cent, cutting exceeds heat-resisting alloy (hardness ≤ 300) the speed when is 24 ~ 30 meters / cent. The graph 2 Z-CARB-AP treatment that establishs series of milling cutter NextpageZ-CRAB-HTA to establish milling cutter to be aimed at high temperature alloy technically undertook distinctive geometrical appearance is designed, also have a variety of patent helix angle, alterable pitch, and can restrain resonance. In addition, its helix angle is bigger, improved pair of heat-resisting alloy thereby cut and cut from the function, also make the balance of treatment and stability got rising. The core ministry structure of elaborate design raised his the intensity in harsh treatment environment and tigidity. In workpiece hardness ≤ 300 when, cutting speed amounts to 27 ~ 40 meters / cent. And hardness ≥ 300 when, cutting speed can amount to 24 ~ 37 meters / cent. Because have the pitch of odd blade, change and tooth form,V-CRAB5 blade establishs milling cutter, can reduce resonance, improve treatment bright and clean degree, reduce cutting force, enhance tigidity, improve manufacturing efficiency. Odd much blade ages if increase tine number again,establish milling cutter, increase 7 blade, 9 blade, 11 blade to wait for example, besides holding afore-mentioned advantages, as a result of minutely feed F=N (Rpm) feed of tine of × Fz(every blade) × Z (blade tine is counted) , accordingly, blade ages the addition of several can make minutely feed and manufacturing efficiency increase in proportion directly. Much blade tine establishs milling cutter general and alveolar much, but alveolar shallow, core ministry is thicker, cutting tool tigidity is tall, life of treatment precision, stability, cutting tool all is able to improve. A lot of established milling cutter to use patent cooling fluidics of SGS (see a picture 3) , pass but the machine tool main shaft that the center offers cooling fluid, refrigerative fluid edge establishs milling cutter outside 4 become 90 ° oil groove and helix chamfer each other position of cutting of one straight understand. It can achieve cooling result better, maintain constant and proper cutting temperature, prevent overheat, decrease adhere and the tumour that accumulate bits, improve cutting speed and cutting tool life, discharge bits quickly, prevent to cut bits to injure workpiece, improve treatment precision and exterior quality. Graph the characteristic that the company of cooling characteristic SGS that 3 Z-Crab establishs milling cutter has high-powered Shuang Ren of a kind of Hi-PerCarb to take bit is; Because be outside former helix chamfer, blade carried reopen on the back to give slot of a helix, constituted double first flank thereby (see a picture 4) . Structure of double first flank makes oriented, centering orders increase, and treatment stability is tall, cooling fluid is expedite, cool performance is good, the function that discharge bits rises greatly, heat in metal cutting is generated little, treatment surface is bright and clean degree tall, the special processing of point protected edge. Coping helix chamfer forms before the two groove that go out are ground to repair on knife face ground horizontal blade, can disjunction cuts bits, increased feed capacity, and reduced axial force. Broach surface has high temperature resistant special Ti-NAMITE-A(AlTiN) coating, can raise cutting rate, have efficient treatment. It besides suiting boat aviation accident to machine material getting to cut, also suit general steel, cast-iron, stainless steel auger cut. Its treatment precision is tall, below a lot of circumstances, but working procedure of opening of leave out bore with a reamer. After can undertake wearing away conveniently on common device grind again. High-powered Shuang Ren of graph 4 Hi-PERCarb takes broach Nextpage composite material and its treatment to use cutting tool composite material is will two plant or the material combination with two kinds of different and characteristic above rises, the made material that makes some kind of specific property. Its base material has colophony, pottery and porcelain and metal commonly usedly to wait, enhancing material basically is fiber material. In the past, fibre glass application is very wide, they and colophony are compound the GFRP that form is called glass reinforced plastics. Composite material AFRP uses fragrant fishing line very more also. Make the carbon fiber that imperceptible carbon crystallizes and makes now with craft of special heat treatment, have good performance because its are qualitative gently again, application is increasingly wide. CFRP of commonly used carbon fiber composite material is it is with carbon fiber enhance material, wait for what form for base material with epoxy resin. The character with carbolic inherent atom is low density, low heat expand rate, hear resistance is good, chemical stability is good, and self-lubricating the gender is good. CFRP hardness is tall (HRC53 ~ 65) , thermal conductivity is poor (the 1/5 ~ 1/10 that thermal conductivity is austenite stainless steel only) , but its than intensity, taller than stiffness, fatigue resistance is good, hear resistance is good. When cutting is machined, as a result of its thermal conductivity is differred, local quantity of heat is centered, easy happening burn; As a result of anisotropy, the intensity between the layer is low, easy generation is statified in treatment, tear off, mao Bian, the blemish such as exterior quality difference; Plus cut bits to be dust shape, pollute an environment, endanger human body health. Reason belongs to difficult treatment material. The cutting principle of composite material and the metal such as carbon fiber and process are different. Metallic cutting is cutting blade is cut make generation of the metal that be cut cuts slippage to form of all kinds the course that cuts bits, and carbon fiber composite material is to pass sharp the crucial point to go to what fine peace keeping cuts off epoxy resin layer breaking off compulsively. Fiber chafes conversely like abrasive wear away cutting tool. Carbon fiber composite material basically is used on plane airframe, its machine reason multi-purpose auger cut and milling. Auger because coping exists,cut the twist drill that uses normally horizontal blade, horizontal blade does not produce cutting effect, it is extruding rolls a fiber only, it is to get the main reason that cuts axial component of force and heat in metal cutting. Plus extreme difference of thermal conductivity of carbon fiber composite material, cause burn very easily. Shuang Ren of 8 4 blade takes the 120 series of SGS company special broach, load allocation is flowing and even, treatment precision is tall, treatment surface quality is good, layer of punish of bore imports and exports, burr is very few, wear away abrasion is small, broach life is long. Especially plus diamond coating Di-NAMITE, its treatment quality is higher, life is longer. The 20-CCR series of SGS company is them it is what design of data of aviation carbon fiber develops to establish milling cutter only, below most circumstance, can reduce eliminate fibrous burst even. Decrease statified come off. Its diameter has metric, imperial two kinds, metric diameter is 6 ~ 12 millimeter. Tooth has belt coating Di-NAMITE mixes diamond not to take coat two kinds. Graph the 5 of all kinds composite material that are SGS establish milling cutter. The of all kinds composite material of graph 5 SGS establishs milling cutter to machine a respect in mill of composite material essence, the 25 series that SGS company still has a kind of unique structure establish milling cutter (see a picture 6) . This series establishs milling cutter to have or so helix at the same time groove and the two circumferential blade that form by them. Because or so helix is right work active force is contrary, original drag force is compressed force is quits, utmost ground reduced composite material what appear in treatment is statified, the injury such as Mao Bian. This series establishs milling cutter to still contain diamond coating Di-NAMITE, rose to establish the hardness of milling cutter and wearability further, what can hold cutting blade for a long time is sharp, reduced cutting negative charge, prolonged cutting tool life, rose to machine quality. Graph chamfer of 6 or so helix milling cutter of composite material essence CNC Milling