A kind of spherical titanium or the preparation method of Titanium PowderTechnical field
The present invention relates to metal and alloy powder preparation field, be specifically related to a kind of spherical titanium or the preparation side of Titanium PowderMethod.
Background technology
Titanium or titanium alloy is light-high-strength metal material, and possesses the characteristic such as highly corrosion resistant, high-fire resistance, by extensivelyBe applied to the fields such as Aeronautics and Astronautics, military project, medical apparatus and instruments.Titanium or titanium alloy is made the micron order with good fluiditySpherical powder, the available means such as injection moulding, isostatic pressing make structure complexity, the irregular component of profile.In recent years,Answer along with a kind of brand-new PM technique increases the rise of material manufacture (3D printing) technology, spherical titanium and titanium alloy powderConstantly expanding with field, market capacity increases increasingly.Increase material manufacturing technology and can utilize high energy according to the data model designedMetal powder is successively sintered by heater, makes the component of anticipated shape.Increase material manufacturing technology can make in a short period of timeStandby go out almost arbitrary shape workpiece, particularly suitable processing precious materials and complex parts, can be applicable to military project part of meeting an urgent need and addThe aspects such as work and car model making.Increase the high energy heater used by material manufacturing technology and typically use laser sintered and electron beamMelted two ways, the most laser sintered heating depth is less, generally uses the particle size range fine powder in 10～45 μm；And it is electricThe sintering depth that son bundle melts is relatively big, the coarse powder that particle size range can be used to be 45～106 μm.Owing to increasing the work of material manufacturing technologySkill characteristic, has had higher requirement to character such as the particle diameter of metal powder material, mobility, purity, oxygen contents.
The method of current domestic preparation spherical titanium or titanium alloy powder mainly has following three kinds:
(1) inert gas atomizer method.The method is to be melted in crucible by bar-shaped raw material, then utilizes high velocity air to incite somebody to actionMelted molten metal sprays from the nozzle of crucible bottom and condenses to noble gas, obtains spherical metal dust.ByDuring atomization, droplet size is uneven, and the spherical metal Powder Particle Size causing the method to be prepared is wide in range, and sphericity is poor, and hasThe existence of hollow bead so that the serviceability of metal dust is affected.
(2) ultrasonic atomizatio method.The method is to be produced at liquid level under the effect of supersonic concentrator by melted metal liquidFrequency Surface tensile wave, when amplitude reaches peak value, liquid can overcome surface tension to deviate from, and forms droplet, prepares after coolingGlobular metallic powder.Globular metallic powder epigranular prepared by the method, good sphericity, but the requirement to equipment is higher,The most overripened.
(3) plasma rotating electrode process.Utilize high-temperature plasma that direct-current arc produces as thermal source by feed metalOr the comsumable melt that alloy is made, cast molten metal liquid aside formation droplet by the rotation of consutrode, thenCondensation obtains globular metallic powder.Spherical metal meal component prepared by the method is easily controllable, sphericity preferable, but to equipmentRequire higher, and there is certain electrode fouling.
Summary of the invention
The technical problem to be solved in the present invention is to provide the preparation method of a kind of spherical titanium or Titanium Powder, by the party's legal systemThe spherical titanium or the titanium alloy powder that obtain have the features such as sphericity height, good fluidity, oxygen content is low, purity is high, narrow particle size distribution.
The preparation method of spherical titanium of the present invention or Titanium Powder is: with titanium silk or titanium alloy wire as raw material, with senseAnswering plasma is that thermal source prepares spherical titanium or Titanium Powder.
More specifically preparation method is: with titanium silk or titanium alloy wire as raw material, uses argon as carrier gas, is sent by raw materialEntering vaporization melting in plasma generator, the melt formed generates metal droplet in the reaction chamber, forms minute sphericalTitanium or Titanium Powder, collect the superfine spherical titanium or Titanium Powder formed, after preparation process terminates, mistake under protective atmosphereSieve the spherical titanium to collect desired particle size or Titanium Powder；Wherein:
Carrier gas flux is 1～6slpm, and raw material rate of feed is 10～600g/min；
The parameter of plasma generator is: power is 1～200KW, and pressure is 13.8～130.9Kpa, central gas flowBeing 5～100slpm, secondary air amount is 15～150slpm, and sheath gas is the mixed gas of argon and hydrogen, wherein argon flow amountBeing 20～300slpm, hydrogen flowing quantity is 1～80slpm.
Further, preparation method of the present invention specifically includes following steps:
1) with titanium silk or titanium alloy wire as raw material, put in feed appliance, whole preparation system is rinsed and hunts leak；
2) in plasma generator, it is passed through central gas and sheath gas, starts high frequency electric source and excite plasma, thenIt is passed through secondary air, progressively regulates system pressure, power and various gas flow to predetermined value；
3) start feed appliance and be passed through carrier gas, making raw material send into plasma with certain speed under the protection of air-flow and send outVaporizing melting in raw device, the melt formed is dispersed as small metal droplet through gas shock in the reaction chamber, underGradually it is cooled into superfine spherical titanium or Titanium Powder during falling, and falls in the powder collector bottom reative cell, in preparationAfter process terminates, sieve to collect the spherical titanium of desired particle size or Titanium Powder under protective atmosphere.
In above-mentioned preparation method, most of micron-sized superfine spherical titanium or Titanium Powder the most directly fallEnter in the powder collector bottom reative cell, a small amount of superfine spherical titanium or Titanium Powder can be taken away when being detached by gas.In order to rightSuperfine spherical titanium or the Titanium Powder of this part are collected, and the method for the invention also includes that utilizing gas to detach part existsThe superfine spherical titanium or the Titanium Powder that are formed in reative cell are further conducted to cyclone classified room, by this part superfine spherical titanium orTitanium Powder is collected in the powder collector bottom cyclone classified room；And attritive powder remaining in air-flow is pulled out at working gasDuring preparation system, being directed to gas solid separation room with working gas and be blocked on the filter of gas solid separation room, gas is thenThrough emptying after filter or recycle after treatment.After preparation process terminates, by the powder in 2 powder collectors is existedSieve to collect spherical titanium or the Titanium Powder of desired particle size under protective atmosphere.
In above-mentioned preparation method, described central gas is preferably argon, and described secondary air is preferably argon.
In preparation method of the present invention, described titanium silk or a diameter of the 0.1 of titanium alloy wire～6mm.
Compared with prior art, present invention is characterized in that
1, use thread titanium silk or titanium alloy wire as raw material, from source, avoid the purity that powder raw material brings notProblem high, that oxygen content is higher；It is prepared titanium or Titanium Powder, institute in conjunction with using the induction plasma method as thermal sourceIt is excellent that the spherical titanium prepared and titanium alloy powder have purity height, sphericity height, good fluidity, low, the narrow particle size distribution of oxygen content etc.Point, the particle mean size of obtained spherical titanium or titanium alloy powder is adjustable in 10～100 μm, pollution that whole preparation process is electrodeless.
2, powder collector is arranged at bottom reative cell and (farther includes to be arranged at the bottom of cyclone classified room), due to reative cell(or cyclone classified room) and operation of sieving afterwards are in protective atmosphere, therefore, receive powder and operation of sieving all at isolation skyCarrying out in the environment of gas, whole process avoids surface oxidation and the moisture absorption of metal-powder.
3, preparation method of the present invention is raw materials used and gas is nontoxic, and preparation process is more than an atmospheric pressureIn the environment of carry out, there is not the danger causing blast owing to leaking into air.
Accompanying drawing explanation
Fig. 1 is the high-frequency plasma equipment schematic diagram used in preparation method of the present invention；
Fig. 2 is the scanning electron microscope (SEM) photograph of the sized spherical titanium powder that the embodiment of the present invention 1 prepares；
Fig. 3 is the scanning electron microscope (SEM) photograph of the spherical titanium alloyed powder that the embodiment of the present invention 2 prepares；
Fig. 4 is the scanning electron microscope (SEM) photograph of the sized spherical titanium powder that the embodiment of the present invention 3 prepares.
Figure is numbered:
1 feed appliance；2 raw materials；3 central gas；4 sheath gas；5 plasma generators；6 secondary airs；7 reative cells；8 receive powderDevice；9 cyclone classified rooms；10 filters；11 gas outlets；12 gas solid separation rooms.
Detailed description of the invention
Below in conjunction with specific embodiment, the present invention is described in further detail, to be more fully understood that present disclosure, butThe present invention is not limited to following example.
The preparation system used in the method for the invention is as it is shown in figure 1, mainly include that feed appliance 1, plasma occurDevice 5, reative cell 7, cyclone classified room 9 and gas-solid separation chamber 12, be respectively arranged with band bottom reative cell 7 and cyclone classified room 9The powder collector 8 of ultrasound wave high-frequency vibration device, realizes sized spherical titanium powder or Titanium Powder and collection by the two powder collector 8.ToolRaw material 2, when using this preparation system, is first loaded in feed appliance 1 by body, and completing the flushing of preparation system, (operation is all in leak detectionSame as the prior art), and be passed through central gas 3, sheath gas 4 and secondary air 6 etc. make system debug stable (operation all with existing skillArt is identical) after, use the mode of centre charging to be sent in plasma generator 5 under the protection of carrier gas by raw material 2 tinselVaporization melting, the plasma high-temperature area in reative cell 7 melts rapidly, and the melt formed rushes through air-flow in reative cell 7Hit and be dispersed as small metal droplet, these droplets fall during be gradually cooled into micro-sized spherical titanium powder orTitanium Powder, the sized spherical titanium powder of formation or Titanium Powder fall in the powder collector 8 bottom reative cell 7, a small amount of sized spherical titanium powder or titaniumAlloyed powder can export to cyclone classified room 9 along with the gas being passed through preparation system from reative cell 7, falls into whirlwind after cyclone classifiedIn powder collector 8 bottom grading room 9, and attritive powder remaining in air-flow is when working gas is pulled out preparation system, with workBeing directed to gas solid separation room 12 as gas and be blocked on the filter 10 of gas solid separation room 12, gas is then through filterEmpty through gas outlet 11 or recycle after treatment after 10.After preparation process terminates, by by the powder in 2 powder collectors 8End sieves to collect the spherical titanium of desired particle size or Titanium Powder under protective atmosphere (usually argon).
Embodiment 1
1) the titanium silk taking a diameter of 0.2mm loads in feed appliance, is then rinsed preparation system with argon and hunts leak；
2) in plasma generator, it is passed through sheath gas (argon flow amount is 30slpm, and hydrogen flowing quantity is 2slpm) and centerGas (argon 8slpm), adjusting system air pressure is 27.6Kpa, opens high frequency electric source and excites plasma, then passes to assist gasFlowing and adjusting uninterrupted is 25slpm, progressively by system air pressure adjustment to 103.4Kpa, system power is adjusted to 15KW；
3) after system stability, open feed appliance start feed with the speed of 12g/min and in feed appliance, be passed through carrier gas(argon, flow is 2slpm), vaporization melting in plasma generator sent under the protection of carrier gas by titanium silk, high at plasmaTemperature area melts rapidly, and the melt formed is dispersed as small metal droplet through gas shock in the reaction chamber, underMicro-sized spherical titanium powder gradually it is cooled into during falling；The micron-sized globular metallic powder of major part falls under gravityEntering in the powder collector bottom reative cell, a small amount of micron particles exports to whirlwind along with the gas being passed through preparation system from reative cellGrading room, falls in the powder collector bottom cyclone classified room after cyclone classified, and attritive powder remaining in air-flow is in workWhen gas is pulled out preparation system, it is directed to gas solid separation room with working gas and is blocked in the filter of gas solid separation roomIn, gas then or recycles through gas outlet emptying after treatment through after filter；
4), after preparation process terminates, the high frequency ultrasound vibration utilizing the vibrating device carried in powder collector to produce makes powder slidingFall, the powder collected bottom bottom reative cell and cyclone classified room in powder collector in the environment of isolation air, obtain spherical titaniumPowder.Gained powder mistake-325 mesh and+1340 eye mesh screens successively under the protection of argon, it is thus achieved that main particle size scope is 10～45The sized spherical titanium powder of μm, the mean diameter of sized spherical titanium powder is 24.1 μm.
Being analyzed the microstructure of the sized spherical titanium powder that the present embodiment prepares, its scanning electron microscope (SEM) photograph is as shown in Figure 2；And it is rightIts sphericity, tap density, mobility and oxygen content are tested, result as described in Table 1:
Table 1:
Embodiment 2
1) titanium alloy wire (component is Ti+6wt.%Al+4wt.%V) taking a diameter of 2mm loads in feed appliance, then usesPreparation system is rinsed and hunts leak by argon；
2) in plasma generator, it is passed through sheath gas (argon flow amount is 75slpm, and hydrogen flowing quantity is 6slpm) and centerGas (argon 25slpm), adjusting system air pressure is 34.5Kpa, opens high frequency electric source and excites plasma, then passes to auxiliaryAir-flow to adjust uninterrupted be 45slpm, progressively by system air pressure adjustment to 110.2Kpa, is adjusted to 60KW by system power；
3) after system stability, open feed appliance start feed with the speed of 50g/min and in feed appliance, be passed through carrier gas(argon, flow is 4slpm), titanium alloy wire sends in plasma generator vaporization melting under the protection of carrier gas, wait fromSub-high-temperature area melts rapidly, and the melt formed is dispersed as small metal droplet through gas shock in the reaction chamber,Minute spherical Titanium Powder gradually it is cooled into during falling；The micron-sized globular metallic powder of major part is at gravityEffect falls in the powder collector bottom reative cell, and a small amount of micron particles is led from reative cell along with the gas being passed through preparation systemGo out to cyclone classified room, fall into after cyclone classified in powder collector bottom cyclone classified room, and fine powder remaining in air-flowEnd, when working gas is pulled out preparation system, is directed to gas solid separation room with working gas and is blocked in gas solid separation roomFilter in, gas then through emptying after filter or recycles after treatment；
4), after preparation process terminates, the high frequency ultrasound vibration utilizing the vibrating device carried in powder collector to produce makes powder slidingFall, the powder collected bottom bottom reative cell and cyclone classified room in powder collector in the environment of isolation air, obtain spherical titaniumAlloy powder.Gained powder mistake-150 mesh and+325 eye mesh screens successively under the protection of argon, it is thus achieved that main particle size scope is 45～106 spherical titanium alloyed powders of μm, the mean diameter of sized spherical titanium powder is 71.3 μm.
Being analyzed the microstructure of the spherical titanium alloyed powder that the present embodiment prepares, its scanning electron microscope (SEM) photograph is as shown in Figure 3；And its sphericity, tap density, mobility and oxygen content are tested, result is as shown in Table 1 above.
Embodiment 3
Repeat embodiment 1, except for the difference that:
Step 1) in, a diameter of 6mm of titanium silk；
Step 2) in, the sheath gas being passed through is: argon flow amount is 300slpm, and hydrogen flowing quantity is 80slpm；Central gas argon streamAmount for 100slpm, is passed through secondary air and to adjust uninterrupted is 100slpm, progressively by system air pressure adjustment to 130.9Kpa,System power is adjusted to 200KW；
Step 3) in, feed appliance is with the speed feed of 200g/min and be passed through carrier gas in feed appliance (argon, flow is6slpm。
Step 4) in, powder mistake-150 mesh and+325 eye mesh screens successively under the protection of argon, it is thus achieved that main particle size scopeBeing the sized spherical titanium powder of 45～106 μm, the mean diameter of sized spherical titanium powder is 72.5 μm.
Being analyzed the microstructure of the spherical titanium alloyed powder that the present embodiment prepares, its scanning electron microscope (SEM) photograph is as shown in Figure 4；And to its sphericity, tap density, mobility and oxygen content characterization result as shown in Table 1 above.