The turning of titanium alloy spare parts is machined

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The special property that titanium alloy has makes its application field more and more extensive. Very high intensity / weight comparing, wonderful tenacity and outstanding corrosion resistance can make titanium alloy can be used at making medical service body of choose and employ persons is embedded, golf lever head and armor of for military use. But, the turning of titanium alloy spare parts machines special however difficulty, division of your machine technology people be terrified by the sight of sth or sb, they think, the super function of titanium alloy weakened his to be able to be machined greatly " ability " , make its cutting treatment has challenge sex extremely. Although this kind of view is reasonable, but not comprehensive. The article discussed the turning of titanium alloy to machine strategy, to mechanical technology division people treatment this kind of use is extensive (wait like ventilator of cycle racing spare parts, underwater) the cutting technology with difficult treatment material and new application will be helped somewhat. Titanium alloy produces business -- the Bill Headland of advanced project expert of company of RTI international metal points out, although a lot of job shops regard titanium alloy treatment as a dangerous road, but the breed range that actually titanium alloy includes is very wide, you must understand what what you machine is which kind of. The brand of titanium alloy is very much, difficulty of some brands treatment is great, and another some of brand is not however such. Business uses pure titanium (CP brand) it is material of alloy of a kind of blame, use at making normally medical spare parts, heat exchanger and glasses frame. CP brand has outstanding corrosion resistance, and relative to character is machined more easily. But compare with photograph of other titanium alloy, its intensity is very low, and stick again soft. After alloy is joined in pure titanium, changed its brilliant posture (crystal structure) , also changed the character of material and machining sex. Be like,included in α titanium alloy and alloy of accurate α titanium nickel, aluminous, vanadium add component. Of alloy of these intermediate brand titanium but cutting sex perfectly. α - brand of β titanium alloy may be included have more aluminium and vanadium. Industrial Ti6Al4V of mainstream titanium alloy is a kind of α - brand of β titanium alloy, included the aluminium of about 6% and the vanadium of 4% among them. Ti6Al4V and its mutation are occupied about what use titanium alloy at present 50% - 70% . The alloy of β brand titanium that added the part such as iron, chromium is most one of brands that process hard. Because have,rupture high tenacity and fight function of tall periodic exhaustion exceedingly goodly, alloy of nickel radical of the machining sex of β brand and Hastelloy reachs similar material close, its typical application example is to make light-duty spring, those who be used at touching hair underwater to fire tactical missile but fold empennage. All sorts of titanium alloy present each not same cutting function. Somebody thinks, machining the time that place of work of a Ti6Al4V needs is to process a steel normally 3 times; And someone says, machining the time that place of work of brand of β of difficult treatment of a Ti5553 needs is treatment double of workpiece of a Ti6Al4V. In turning treatment, the character with titanium the mainest alloy heats up conductibility to differ namely. Be absorbed very hard by workpiece as a result of the high temperature of the generation when cutting and gather on blade of cutting tool cutting, overmuch quantity of heat makes cutting blade and cut chemical reaction produces between bits and produce crescent moon to wear away depression. Titanium alloy still has treatment sclerosis tendency, accordingly, cut and passing is not extruding purify metal crucial. In addition, although titanium alloy has very high strength, but also have inferior stretch model amount at the same time, this is meant compare with other data phase, titanium alloy photograph is stretch to be being provided more and leave cutting sword more easily (be in especially when carrying cutting gently) . Consider these character of titanium alloy integratedly, realize the turning treatment of titanium alloy to succeed, the key is the balance that must achieve rate of cutting speed, feed and cutting deepness. Cutting speed is the chief factor that affects generation of heat in metal cutting. Turning expert Stefan Gyllengahm of Shanteweikekeleman once spent 3 years of half time to develop cutting tool shop sign for tool manufacturer. During this, he undertook in the lab the cutting of Ti6Al4V experiments, the result makes clear, the choice of cutting speed must very careful: Below certain circumstance, rise when cutting speed 10% - 15% , criterion cutting tool life can drop from 40 it is 6, the adjustment that this indicates cutting rate range is too big. He returns discovery, when with won't shrinking the cutting speed of life of short cutting tool undertakes turning, if raise feed rate, can reach the critical temperature of life of a cutting tool having damage, because be put in the ultimate range with an overmuch quantity of heat. Appearance of cutting tool geometry cuts bits configuration to heat up a respect in order to come loose to having crucial effect in control. Wider with the thinner cutting that cut bits to expand to be being formed the interface between bits and cutting blade is accumulated, can reduce quantity of heat to be in thereby of cutting blade gather. If cut bits thinner, the quantity of heat of generation is less, cutting speed is OK a few faster. For example, make appliance has - the C of horn of lead of 5 ° standard (80 ° ) when diamond razor blade undertakes rough machining, the ply that cut bits and feed rate are roughly equal; And the metal that the square bit that uses installation lead horn to be 45 ° can make be excised (and heat in metal cutting) diffuse along longer cutting blade. Round razor blade is reasonable by admiral this one concept developed acme (but be confined to cut deep lesser when) . Gyllengahm expresses, cutting normally deep lesser when, use round razor blade to be able to be obtained very thin cut bits. But, considering have 12.

The round razor blade of 7mm inscribed circle is being cut deep its are effective when be more than 2mm lead horn can be reduced, because this had better use square bit, because be being cut identically,fall greatly, square razor blade still has part of 45 ° lead. Bill Skoretz is the manager of branch of treatment of Patriot Forge company, this company is offerred wait for of all kinds raw material to alloy of special brand aluminium alloy, titanium from low-alloy steel, stainless steel, the client that also can be a company sometimes machines titanium alloy spare parts. When the challenge that faces when place of alloy of discussion turning titanium, he reviewed turning rolling mill to use the experience of cooling fluid shower nozzle mainly. This kind anticorrosive titanium alloy brand has abrasion. Because titanium alloy possesses resilience, because this must be used angle of cutting tool geometry, and the appearance that should value cutting tool head. If the bottom horn of cutting tool or before part is too small, cutting tool can begin to produce pulling force, bring a lot of issues thereby. Accordingly, must be in cutting tool head geometrical angle and to cutting blade prop up between find optimal balance. Skoretz described the development current situation of cutting cutting tool from historical angle. Before development gives hard alloy cutting tool, basically use high-speed steel cutting tool to come cutting steel products. The occurrence of hard alloy cutting tool makes use geometrical angle becomes a possibility, but the machine tool must have enough power. Razor blade of the horn before losing can make titanium alloy material produces fold or extruding only, and excise its hard. But he is warned again say, if of bit before part is too large, also can form pulling force to titanium alloy material. Accordingly, must be in pressure stress and pull the balance is found between stress. He mentions the past to ever had been used on cutting blade preparation has 0.

1mm or 0.

The razor blade of the T of 13mm first flank, "Main the safety for edge, cannot use too sharp cutting blade, because it cannot be maintained how long. " he still used liquid of oil radical cutting in treatment, but basically be to use its lubricant and characteristic and not be cooling power. Other job shops also has method of different titanium alloy turning, because the purify treatment of any material is put in the solution that all sorts of differring. The business that Rayco Machine company has 30% is spare parts of treatment racing bicycle, have among them a lot of it is the titanium alloy spare parts with high price, because group of top class racing bicycle is willing to attach most importance to a quantity the premium of spare parts defray with light, high intensity, the least weight that allows in order to make their racing bicycle maintains in regulation but still can be opposite at the same time its are whole of automobile body weight distributing retain control. For example, reduce rotate part and blame suspension part (like wheel and brake component) quality is OK and effective rise acceleration and hold control function. The titanium alloy that Rayco company turning machines includes to move at the spare parts between clamp of apply the brake and rotor in the spare parts. Like Skoretz, greg Cox of Rayco company president also expresses, for successfully turning titanium alloy, need uses the method of balanced give attention to two or morethings. He thinks, when choosing cutting parameter, very important when was being machined namely cannot elbow workpiece material, produce treatment sclerosis easily otherwise, cause very big trouble to treatment. The treatment parameter that Rayco company uses normally is: Cutting speed 120 Sfm, feed 0.

13 - 0.

20mm. Cutting deepness is very important also. Same, cut moderately deep it is optimal choice. What Rayco company uses is the biggest cut deeply 0.

8 - 1mm. The titanium alloy spare parts of Rayco company machines batch to be able to be as high as 200, but it is to be in mostly 5 - 20 between. Cox expresses, rayco company also is improving technology continuously, but when involving cutting parameter must scrupulous, because titanium alloy is quite costly, cannot lest act recklessly brings about a spare parts to discard as useless. Of titanium alloy rise in price very fast, last year from 47 dollars / the pound rises to 68 dollars / pound. The price of titanium alloy tall look forward to also makes the inventory of workpiece material constrictive. Dive the research and development of company of equipment manufacturer Atomic Aquatics and Scott Holland of production branch general manager express, when the alloy that use titanium machines underwater respirator, "We always try to improve treatment efficiency ceaselessly, with shortening workpiece of more of handling time, treatment is mixed prolong cutting tool life. " but when they try to machine more spare parts, subsequently and those who come is cutting tool breaks off suddenly. Accordingly, holland hope can achieve optimal and balanced dot, but this kind balanced be not is number and program only. Holland has titanium alloy of nearly 10 years to machine experience, the configuration that he also depends on observation work and cutting tool, listen attentively to cutting noise to master this kind is balanced. Holland expresses, treatment titanium alloy also can be compared simple, "If use the time that sharp cutting tool estimates by oneself to change a knife, can machine titanium alloy inside narrow range only. You can undertake trying by your means, but not certain get the desired result. The treatment of titanium alloy has certain law, if you grasped these patterns, OK handy. " the cutting technology that increasingly wide application promoted titanium alloy to attach most importance to a dot with alloy of efficient turning titanium develops. Company treatment manages Shanteweikekeleman to support senior manager Chris Mills to emphasize with the technology, when turning titanium alloy, chemistry wears away is main cutting tool failure mechanism, and cutting high temperature quickened chemistry to wear away. When boiling hot cut bits to had delimited when face of the knife before cutting tool, meet actually from inside bit " pull out " cobaltic. Mills introduced to reduce the method of cutting temperature through two measure: The first pace is to use cutting tool geometry to design (if use the square bit that takes part of 45 ° lead or round bit) will reduce the thin thickness that cut bits, in order to drop cutting temperature, reduce the crescent moon that causes from this to wear away depression, can use finally taller feed is led and prolong cutting tool life; The 2nd pace is the high-pressured cooling fluid that makes appliance has special pattern. This kind of cooling fluid has high-pressured power not only, and present a form of very exact laminar flow eject, can form between face of the knife before cutting bits and razor blade " water wedge " , cut bits with be being held in the palm, make its and before the contact of knife face is the smallest change, avoid to produce crescent moon to wear away depression thereby. The pressure of cooling system is this kind of Jetbreak of Shanteweike 1000 - 3000psi, use a diameter 1.

The nozzle of 27mm and standard emulsification cooling fluid, it has cooling effect not only, and can arise hold the lift that cuts bits in the palm, can reduce cut bits and before the attrition between knife face and temperature. Use this system to be able to make cutting rate rises 50% . Mills described use integratedly afore-mentioned two kinds drop in temperature politic effect: Use - the CNMG razor blade of horn of 5 ° lead with optimized cutting parameter (cutting speed: 40m/min, feed rate: 0.

3mm/rev) when machining titanium alloy, cutting tool life is 20 minutes about; And when the square bit that uses round razor blade or part of 45 ° lead undertakes machining, can raise cutting rate 50 - 60m/min, feed rate rises 0.

4mm/rev, can maintain similar cutting tool life. Because more workpiece material can be excised in same time, use square razor blade to be able to make productivity breaks up merely time, if use high-pressured refrigeration system again, still can raise cutting rate again 50% . The channel that high-pressured cooling fluid must carry interior of machine tool main shaft (is not exterior conduit) carry. Cooling fluid sheds a when via Shanteweike Capto changes tool collet quickly to go up special connector, control its pressure by Capto. When installing a machine tool, can install system of refrigeration of this kind of high pressure easily. To often machining titanium alloy spare parts (especially high large aviation component) workshop, raise the productivity of 50% to be worth their investment to buy collet of special cutting tool and the machine tool that installed high-pressured refrigeration system. System of refrigeration of this kind of high pressure has distinct advantage when turning titanium alloy, because won't resemble treatment,other workpiece material produces crescent moon to wear away depression in that way. CNC Milling CNC Machining