Coating hard alloy establishs TC4 of milling cutter cutting to emulate research

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The α that TC4 is a model - β titanium alloy, have mechanical property function of low temperature of good, taller than intensity, high temperature admirable, corrosion resistance can be exceedingly good wait for outstanding characteristic, already made in aerospace, car, shipping, the domain such as biology medicine gets applied extensively. But can look from cutting processability, the cutting temperature with low hot conductivity, high TC4 makes cutting tool wears away accelerate, loss of efficiency of cutting tool loss of life, treatment. Cutting fluid is joined to be able to improve cutting tool service life when research makes clear treatment [1] , but use cutting fluid can raise finished cost, aggravating environment is polluted [2] , because this often uses dry cutting,machine means. The knife in choosing material of reasonable cutting tool coating and coating ply to be able to overcome dry cutting effectively - the defect that bits interface attrition and cutting temperature increase, it is the efficient way that raises titanium alloy to machine efficiency. Craft of cutting tool coating basically uses PVD or CVD2 is planted technology. Commonly used coating material includes TiN, TiCN, TiAlN and Al2O3. A lot of scholars experiment through cutting or finite yuan of emulation research the coating influence to function of cutting tool cutting. Zhang Shijun [3] used analytic method to announce the influence of coating material and coating ply to temperature of cutting tool cutting the rule, ply of smaller, coating jumps over the hot conductivity that computation makes clear coating material as a result big, the cutting temperature of coating cutting tool is lower. T.

Ozel [4] uses cutting experiment and three-dimensional and finite yuan emulation method studied not temperature of the cutting force when coating, TiAlN coating and cutting tool of TiAlN/CBN coating hard alloy are machined to TC4, cutting and influence of cutting tool tatty, research discovers the cutting function of TiAlN coating cutting tool is optimal. M.

Nouari [2] uses cutting to tried proved recipe law to consider not coating and multilayer coating (alternant coating of TiC, TiN and TiCN, 9 in all 10 μ M is thick) the cutting tool life when hard alloy cutting tool does cutting titanium alloy and treatment surface quality, got the cutting speed limits when cutting tool service life is the longest, use at the same time finite yuan of analytic law imitate the cutting temperature when 2 kinds of cutting tool machine titanium alloy distributings cloud atlas. Irfan [5] is used not coating and different coating material (TiCN+Al2O3+TiN and Al2O3) temperature of the cutting force when cutting tool cutting is machined, cutting, the result shows the cutting temperature lowest of Al2O3 coating cutting tool. The article is used above all finite AdvantEdge builds yuan of analysis software establish milling cutter three-dimensional milling model, the cutting strength that gains milling TC4 experiment next and finite yuan of imitate result is comparative with test and verify the validity of three-dimensional milling model, pass finally finite yuan of coating ply that analyses hard alloy to establish milling cutter (1 μ M, 2 μ M, 2.

5 μ M, 3 μ M, 4 μ M) reach coating material to reach unit cutting to temperature of cutting tool cutting, cutting can influence rule. Coating material cent is 5 kinds: Not coating, TiAlN (4 μ M) , Al2O3 (4 μ M) , Al2O3/TiN (M of μ of 2 μ M/2) , TiAlN/Al2O3/TiN (M of μ of M/1 of μ of 2 μ M/1) , number is ordinal for Ⅰ , Ⅱ , Ⅲ , Ⅳ , Ⅴ . Establish milling cutter three-dimensional milling is finite yuan of model and material of 1 TC4 of experiment test and verify this compose model is finite yuan of analysis is medium, model of mathematical data flow stress is being inputted below requirement of ratio of tall meet an emergency is descriptive workpiece material the effective method of this compose behavior [6] . The stress of going from place to place of workpiece material defines the function that is rate of meet an emergency, meet an emergency and temperature normally. The model of power index data of this compose equation in AdvantEdge software is like type (1) be shown: σ ε P, · ε , Θ of · of ε of · of Γ of · of P) of ε of T= G ((T) , (1) in σ type, ε P, · ε , ε of · of Γ of · of P) of T=g (ε is σ plasticity should · Θ changes (T, ) ε P, · ε , ε of · of Γ of · of P) of T=g (ε is hard Θ of · of meet an emergency (T σ changes function; ε P, · ε , σ of ε of · of Γ of · of P) of T=g (ε is · Θ should (change T) rate, ε P, · ε , ε of · of Γ of · of P) of T=g (ε is · Θ should (T changes) the coefficient of sensitivity that lead σ ; T is temperature, ε P, · ε , Θ of · of ε of · of Γ of · of P) of T=g (ε (T) is hot bate coefficient, this compose equation coefficient of TC4 is concerned in warehouse of AdvantEdge software material is being used when the article is emulated. If the chemical composition of alloy of titanium of workpiece material TC4 expresses 1 to show. The physical property of alloy of titanium of workpiece material TC4 includes: Stretch model measures E=114GPa, heat up conductivity λ =7.

05~16.

24W/m · ℃ , cp =2 of specific heat capacity.

27~3.

81N/mm2 · ℃ , poisson compares υ =0.

34, density ρ =4428kg/m3, =9 of α of thermal diffusion coefficient.

℃ of 6 × 10-6/ [4, 6] . The experiment uses coating of TiAlN of Fu of cutting tool besmear, and ply is 5 μ M, if the hot conductivity of TiAlN expresses 2 to show, stretch model measures E=380GPa, small hardness is 3300HV. 2 establish milling cutter three-dimensional milling is finite yuan the model is used finite the analysis establishs imitate of yuan of analytic software AdvantEdge milling cutter is three-dimensional the treatment process of TC4 of milling titanium alloy. Attrib border condition defines the whirligig that circles Z axis for cutting tool and linear feed motion, use Lagrange method has consideration. Use reseau redraw cent, get used to reseau technology and reseau astringent technology oneself in order to obtain best reseau (graph 1) . The reseau type of cutting tool and workpiece all is the tetrahedral unit that 12 freedom spend 4 node. Of workpiece the biggest reach the smallest unit size to be 2mm respectively, 0.

15mm, of cutting tool the biggest reach the smallest unit size to be 1mm respectively, 0.

1mm. Test and verify of 3 milling experiment is finite the accuracy of this compose model mixes the analyses precision to rely on place to build greatly three-dimensional model of yuan of software and use data accuracy. The article is passed contrast force of experiment earning cutting and force of cutting of emulation analysis earning the accuracy of this compose model mixes the three-dimensional model that builds with place of test and verify and material accuracy, namely finite the effectiveness of yuan of emulation analysis. Milling experiment uses DAEWOOACE-V500 vertical machining center, top rotate speed is 10000r/min, power is 15kW; Use Kistler-9275A measures power instrument to measure power of milling process cutting; Use cutting tool establishs milling cutter for integral horniness, cutting tool parameter and cutting parameter see a table 3, watch 4. If parameter of geometry of the cutting tool in emulating expresses 3 to show, setting cutting tool circles Z axis to rotate 720 ° , imitate cutting time 0.

06s, if contrast of force of cutting of direction of the X that experiment and imitate get, Y, Z pursues 2 are shown. The cutting condition of each project in the graph is as follows: Ⅰ : V=60m/min, fz=0.

1mm/Z, ae=2mm, ap=3mm; Ⅱ : V=60m/min, fz=0.

15mm/Z, ae=3mm, ap=5mm; Ⅲ : V=90m/mi N, fz=0.

05mm/Z, ae=3mm, ap=5mm; Ⅳ : V=90m/min, fz=0.

15mm/Z, ae=2mm, ap=1mm. Nextpage by the graph 2 knowable, the cutting power that the experiment measures gets with emulation analysis cutting force has same metabolic tendency: When cutting speed 90m/min when each are less than cutting speed to be 60m/min apparently to cutting force each to cutting force; When cutting rate is same, the addition that follows deepness of every tine feed, cutting to cutting force each and elevatory. When milling condition is same, experiment and emulate force of cutting of direction of gotten X, Y, Z the biggest error is respectively 7% , 14% , 14% , test result and emulation result be identical are good, test and verify establish milling cutter three-dimensional milling is finite yuan of validity of the model. Coating ply and coating material are three-dimensional milling is finite we adopt yuan of emulation model build three-dimensional milling is finite material of yuan of model research coating and its coating ply (not coating, TiAlN (4 μ M) , Al2O3 (4 μ M) , Al2O3/TiN (M of μ of 2 μ M/2) , . If the hot conductivity of coating material expresses 2 to show. In the model, cutting tool diameter is 10mm, tine number is 4, the horn before radial is 10 ° , helix angle is 30 ° , the horn after radial is 12 ° , the horn after axial is 1.

5 ° , if cutting parameter setting expresses 5 to show. Result and discussion unit cutting can be the total energy that material of workpiece of purify unit volume wastes. When the index that should use unit cutting to be able to machine function as judgement cutting, unit cutting can mean cutting property higher lower [8] . In establishing procedure of milling cutter milling, change as a result of what milling ply spends as cutting tool corner coming back and change (graph 3) , the trade that can use cutting force and cutting area directly because of this unit cutting is direct token. W.

Polini [9] thinks unit cutting can be tangential the function of cutting force, unit cutting can but by type (2) get: Ae of · of Ap of · of Ec=Fc · Vt/va, (2) in type, ec is unit cutting can, fc is tangential cutting force, vt is cutting speed, va is speed of every tine feed, ap is axial cutting deepness, ae is radial cutting deepness. According to the graph 3 shown geometry concern, tangential cutting force and law to cutting force but by type (3) computation reachs: Fc =Frsin δ , ft=Frcos δ , (3) among them, δ =tan1(FyFx)12cos1(12ap (1-2ap/DD) ) , f X, F Y is force of cutting of direction of X, Y respectively, d is;Fc of cutting tool diameter it is personal cutting slightly; Ft is a law to cutting force; Fr is cutting join forces. The influence that 1 coating ply can reach temperature of cutting tool cutting to cutting of cutting force, unit is mixed in parameter of identical cutting tool geometry the condition issues cutting dosage, force of temperature of cutting of the cutting tool when using different coating ply to establish TC4 of milling cutter cutting, cutting and unit cutting can if graph 4~ pursues,imitate analysis parts as a result show 6 times. Nextpage by the graph 4 knowable, the cutting temperature of coating cutting tool is less than not coating cutting tool, and as the addition of coating ply temperature of cutting tool cutting is reduced gradually. This shows coating has heat barrier effect, its inferior hot conductivity can prevent quantity of heat to flow to cutting tool. Zhang Shijun [the ply that 3] studies to make clear coating material is bigger, knife face temperature is jumped over before tall, then by the more of quantity of heat that cuts bits to take away. Coating is accordingly thicker, the quantity of heat that passes into cutting tool is less, temperature of cutting tool cutting is lower. By the graph 5 knowable, not of coating cutting tool each all are more than coating cutting tool to cutting component of force, and after appreciably increases, the addition that cutting force follows coating ply keeps stable first, demonstrative coating ply is lesser to cutting power influence. By the graph 6 knowable not the unit cutting of coating cutting tool can be the smallest, unit cutting can increase along with coating ply and increase. Because increase along with coating ply,this is, thermal drop of cutting tool cutting is small, and the grow in quantity of quantity of heat that passes into workpiece, advanced knife face forms TC4 bate felt the tumour that accumulate bits, make cutting blade no longer sharp, cutting becomes difficult, unit cutting can increase. Analyse by above knowable, the cutting temperature of cutting tool of coating of different coating ply, each all are less than to cutting component of force not coating cutting tool, accordingly, cutting tool of coating of the application below identical cutting condition can raise cutting tool durability. As the addition of coating ply, each to cutting component of force cutting of low, unit can add thermal drop of basic and changeless, cutting, because this uses the coating of appropriate coating ply,cutting tool can obtain good cutting machine function. The influence that 2 coating material can reach temperature of cutting tool cutting to cutting of cutting force, unit is mixed in parameter of identical cutting tool geometry the condition issues cutting dosage, force of the cutting temperature when using different coating material to establish TC4 of milling cutter cutting, cutting and unit cutting can if graph 7~ pursues,imitate analysis parts as a result show 9 times, among them, Ⅰ is not coating; Ⅱ is TiAlN; Ⅲ is Al2O3; Ⅳ is Al2O3+TiN; Ⅴ is TiAlN+Al2O3+TiN. Graph 7 medium cutting temperature distributing for temperature of cutting tool cutting medium highest temperature. By the graph 7 knowable, the cutting temperature of cutting tool of all sorts of coating material coating all under not coating cutting tool, the lowest of temperature of cutting tool cutting of Al2O3 coating. Because,this is: The quantity of heat of the generation in cutting treatment sends work partly, one part is cut bits is taken away, one part is passed into, the hot conductivity of WC/Co of cutting tool base material is the biggest, because be passed into below this identical cutting condition not the quantity of heat of coating cutting tool is the biggest, bring about not the cutting temperature of coating cutting tool is highest. The hot conductivity of Al2O3 lifts along with temperature and reduce, the hot conductivity of WC/Co, TiN, TiAlN all lifts along with temperature and increase (watch 3) , the temperature below same condition is higher, the show of low hot conductivity of Al2O3 is more apparent. As a result of,identical cutting condition falls, the hot conductibility of Al2O3 coating is brought about character pass into the grow in quantity of quantity of heat that cuts bits and work, the quantity of heat that conducts cutting tool decreases, because of the temperature lowest of cutting tool of this Al2O3 coating. Finite temperature of yuan of cutting tool cutting that analytic model forecasts if the graph is shown 10 times,distributing, temperature of place of point of a knife is highest, gradient of pointed direction temperature reduces perpendicular Yu Dao, because this besmears on base material WC/Co Fu heats up the coating stuff with low conductivity to be able to drop temperature of cutting tool cutting, improve cutting tool service life. By the graph 8 knowable, not the cutting power of coating cutting tool is the greatest, the cutting force of Al2O3 coating cutting tool is the smallest. Because the hot conductivity of WC/Co of the base material below coequal condition is highest,this is, and the hot conductivity of Al2O3 coating is inferior and lift along with temperature reduce, use below identical cutting condition not the quantity of heat that coating cutting tool passes into workpiece is least, and the quantity of heat that cutting tool of use Al2O3 coating passes into workpiece is the biggest, as cutting produce bate above all into workpiece of cutting of cutting tool of coating of travel use Al2O3 and bate rate is top, consequently easier cutting, cutting force is the smallest. By the graph 9 can see, monolayer coating (TiAlN, Al2O3) reach 3 coating (TiAlN+Al2O3+TiN) the unit cutting of cutting tool can is worth approximate, not cutting of unit of coating cutting tool can be the smallest, because the coating on cutting tool makes the circular arc radius of blade of cutting tool cutting increases,this is, cutting tool no longer sharp, bring about cutting to become difficult thereby, unit cutting can increase. 2 monolayer coating, coating and not the unit cutting of coating cutting tool can differ respectively 26% , 28% . Analyse by above knowable, force of the temperature of cutting tool cutting of cutting tool of coating of different coating material, cutting all is less than not coating cutting tool, and the unit cutting of cutting tool of coating of the smallest; can compare force of the cutting temperature of Al2O3 coating cutting tool, cutting not coating cutting tool is big. Force of the cutting temperature that considers cutting tool integratedly, cutting and unit cutting can be knowable, below condition of identical coating ply, the cutting function of Al2O3 coating cutting tool is best. The article built conclusion hard alloy establishs alloy of titanium of TC4 of milling cutter milling three-dimensional milling is finite yuan of model, studied coating material and coating ply change to reach unit cutting to force of temperature of cutting tool cutting, cutting can influence, get the following verdict: (1) the cutting temperature of coating cutting tool all under not coating cutting tool; Identical coating material, coating ply is bigger, temperature of cutting tool cutting is lower; Different coating material, hot conductivity is smaller, temperature of cutting tool cutting is lower. (2) of coating cutting tool each to cutting force all under not coating cutting tool. The change that force of cutting of direction of X, Y, Z follows coating ply and coating stuff changes inside lesser limits, coating is lesser to cutting power influence. (3) not the unit cutting of coating cutting tool can be the smallest, the unit cutting of coating cutting tool can increase along with the addition of coating ply, below condition of identical coating ply, the cutting function of Al2O3 coating cutting tool is best. CNC Milling CNC Machining