The treatment characteristic of titanium alloy and craft are analysed

4kg/dm3) , weight is light, but its are more than steel of extra high strength however than intensity. (2) hot strong sex is tall. The thermal stability of titanium alloy is good, in 300 ～ 500 ℃ condition falls, its intensity compares aluminium alloy about 10 times taller. (3) chemical active is big. Titanium can produce strong chemical reaction with the material such as the oxygen in air, nitrogen, carbon monoxide, vapor, tiC and TiN sclerotic layer are formed in the surface. (4) thermal conductivity is poor. Titanium alloy thermal conductivity is poor, titanium alloy TC4 is in the thermal conductance L=16 when 200 ℃ .

8W/m · ℃ , coefficient of thermal conductivity is 0.

036 calories / centimeter ℃ of · second · . Fabricating characteristics of titanium alloy cutting is analysed above all, titanium alloy coefficient of thermal conductivity is low, it is the 1/25 of the 1/4 of steel, aluminous 1/13, copper only. Come loose because of cutting area heat is slow, go against hot balance, in cutting treatment process, medicinal powder heat and cooling effect are very poor, form high temperature in cutting area easily, the spare parts after treatment is out of shape spring back is big, cause torque of cutting cutting tool to increase, point wears away fast, durability is reduced. Next, the coefficient of thermal conductivity of titanium alloy is low, make heat in metal cutting is accumulated send out not easily within the small area area near cutting knife, force of knife face attrition is increased before, discharge bits not easily, heat in metal cutting sends out not easily, quicken cutting tool to wear away. Finally, active of titanium alloy chemistry is tall, reaction has easily with cutting tool material in the treatment below high temperature, form dissolve apply, diffuse, cause stick a knife, burn a knife, break the phenomenon such as the knife. The characteristic of alloy of titanium of machining center treatment (1) machining center can machine many spare partses at the same time, improve manufacturing efficiency. (2) can raise a spare parts to machine precision, product consistency is good. Machining center has cutting tool to compensate a function, can obtain the treatment precision of machine tool itself. (3) have extensive adaptability and bigger treatment flexibility. (4) can realize one machine much can. Machining center can undertake milling, bore, bore hole, a series of treatment such as tap. (5) can undertake accurate costing, control produces plan. (6) do not need special fixture, but managing cost funds, shorten production is periodic. (7) the labor intensity that can reduce a worker greatly. (8) can use the CAD/CAM software such as UG to undertake much axis is machined. The choice of cutting tool material chooses cutting tool material to should satisfy following requirement: (1) enough hardness. The hardness of cutting tool must want ambitious at titanium alloy hardness. (2) enough strength and tenacity. Because very big torque and cutting force should bear when alloy of titanium of cutting tool cutting, because this must have enough strength and tenacity. (3) enough wearability. Because titanium alloy tenacity is good, blade of the cutting when treatment wants sharp, accordingly cutting tool material must have enough fighting to wear away ability, such ability reduce treatment sclerosis. This is the parameter with the mainest cutting tool of alloy of choice treatment titanium. (4) cutting tool material and titanium alloy add up to ability to want difference in person. Because titanium alloy is chemical active is tall, because this wants to avoid cutting tool material and titanium alloy to form dissolve apply, diffuse and become alloy, cause stick the knife, phenomenon that burn a knife. The cutting test that has through material of commonly used to home cutting tool and material of foreign cutting tool makes clear, use ideal of effect of tall cobaltic cutting tool, cobaltic main effect is to enhance sclerotic result 2 times, raise the hardness after red rigid and heat treatment, have at the same time taller tenacity, wearability, good medicinal powder hot sex. The geometrical parameter of the cutting tool of fabricating characteristics decision of the alloy of geometrical parameter titanium of milling cutter and presence of common cutting tool are larger distinction. (1) helix angle β : Choose lesser helix to promote role, increase the chamfer that discharge bits, platoon bits is easy, medicinal powder heat is fast, the cutting in also reducing cutting to machine a process at the same time fights force. (2) before horny γ : The point when cutting is sharp, cutting is light, avoid titanium alloy to produce overmuch heat in metal cutting, avoid to produce sclerosis 2 times thereby. (3) hind horny α : Reduce where a thing can be put to best use wear away speed, be helpful for coming loose hot, durability also gets very old rate rise. Cutting parameter chooses treatment of titanium alloy machine to should choose inferior cutting career, proper feed, cut reasonably measure greatly with finish machining, refrigeration wants sufficient. (1) cutting speed Vc: Vc=30 ～ 50m/min. (2) feed F: Bigger feed is taken when rough machining, finish machining and semifinishing machining take the feed of moderate. (3) cutting deepness Ap: Ap=1/3d is advisable, titanium alloy affinity is fine, discharge bits difficulty, cutting deepness is too big, can cause cutting tool to stick a knife, burn a knife, rupture phenomenon. (4) C of α of finish machining surplus: Moderate, layer of titanium alloy case hardening is made an appointment with 0.

1 ～ 0.

15mm, surplus is too small, edge cutting is on sclerotic layer, cutting tool wears away easily, should avoid sclerotic layer treatment, but cutting surplus shoulds not be too big. Treatment of alloy of cooling fluid titanium had better not use chloric cooling fluid, avoid generation to toxicant pledges and cause hydrogen fragile, also can prevent stress of titanium alloy high temperature to corrode craze. Can choose synthetic water-solubility emulsion, also can match cooling fluid oneself. The cooling fluid when cutting is machined should assure enough, speed of cooling fluid loop wants fast, cutting fluid discharge and pressure want big, machining center deserves to have special and cool spray head, should notice to adjust only can achieve expect the result. Pass the characteristic analysis of pair of titanium alloy, the treatment craft with correct, scientific staff, can reduce cost, improve manufacturing efficiency. CNC Milling CNC Machining