CN114210987A - High-volume-fraction particle reinforced titanium-based composite material powder and preparation method thereof - Google Patents
High-volume-fraction particle reinforced titanium-based composite material powder and preparation method thereof Download PDFInfo
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- C22C32/0047—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with carbides, nitrides, borides or silicides as the main non-metallic constituents
- C22C32/0078—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with carbides, nitrides, borides or silicides as the main non-metallic constituents only silicides
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- B22F9/00—Making metallic powder or suspensions thereof
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- B22F2009/0848—Melting process before atomisation
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Abstract
The invention provides high-volume-fraction particle reinforced titanium-based composite material powder and a preparation method thereof, wherein the preparation method of the high-volume-fraction particle reinforced titanium-based composite material comprises the following steps: designing reinforced titanium-based composite material components, wherein the reinforced titanium-based composite material components comprise a matrix titanium alloy A, an intermediate alloy B and in-situ self-generated reaction additive particles C; uniformly mixing the intermediate alloy B and the in-situ self-generated reaction additive particles C, and pressing into an electrode rod; carrying out vacuum consumable melting on the electrode bar to carry out in-situ reaction on the matrix titanium alloy A, the intermediate alloy B and the in-situ self-generated reaction additive particles C to obtain a high-volume-fraction particle reinforced titanium-based composite ingot; heating and remelting the cast ingot serving as an electrode in a vacuum skull furnace, pouring the cast ingot into a mold, and preparing a bar for powder making; and carrying out electrode induction melting and gas atomization on the bar to prepare powder, thus obtaining the high-volume-fraction particle reinforced titanium-based composite material powder.
Description
Technical Field
The invention belongs to the field of metal matrix composite and powder metallurgy, and particularly relates to a preparation method of high-volume-fraction particle reinforced titanium matrix composite powder.
Background
The particle reinforced titanium-based composite material has excellent comprehensive properties such as low density, high strength, high hardness, high specific stiffness, specific modulus and the like, and can meet the requirements of high performance and light weight of key devices in the field of aerospace. The high volume fraction particle reinforced titanium-based composite material can obviously improve the elastic modulus, yield strength, tensile strength and rigidity of the composite material by introducing the reinforcing body with the volume fraction of more than 10%. However, due to the increase of the volume fraction of the hard ceramic particles, the deformation processing interval of the titanium-based composite material is narrowed, the material can hardly be subjected to subsequent deformation processing, cracks are easily generated, and the material is scrapped, so that the further engineering application of the material is greatly influenced.
The forming process represented by additive manufacturing or powder metallurgy shows great advantages in the aspect of near-net forming, and the high-volume particle reinforced titanium-based composite material is combined with the high-volume particle reinforced titanium-based composite material, so that the requirements of high strength, high modulus and high rigidity of aerospace equipment parts can be met. The existing particle reinforced titanium-based composite material powder used in additive manufacturing or powder metallurgy is mainly characterized in that matrix metal powder and reinforcement particles are mechanically mixed, so that the reinforcement particles are attached to the surface of matrix spherical powder, and the powder mixed by the method has the problems of powder uniformity and defect control in the preparation process.
Patent CN110340371B discloses a method, which comprises pressing titanium alloy and reinforcement into electrode, preparing ingot, forging, drawing, machining into powder rod, atomizing to obtain powder with uniform mixture of reinforcement and matrix alloy. However, for the titanium-based composite material with high volume fraction particle reinforced, although the titanium-based composite material has excellent high-temperature strength and mechanical properties, the plastic deformation capability is poor, cracking and brittle failure phenomena are easy to occur in the deformation processes such as forging, and the bar material required for powder preparation is difficult to prepare in a forging deformation mode; in addition, the powder preparation process is complex in flow, and is not beneficial to mass production of the titanium-based composite material powder.
The complex integrated component is directly formed by using the high-volume particle reinforced titanium-based composite material powder, the problem of cracking in subsequent hot working forming is avoided, and the method becomes an important way for determining one-time direct forming of the high-rigidity and high-modulus titanium-based composite material complex component.
Disclosure of Invention
The invention aims to provide a preparation method and application of high-volume-fraction particle reinforced titanium-based composite material powder, and solves the problems of forging deformation cracking and complex powder preparation process caused by a high-volume-fraction reinforcement in the existing process.
The purpose of the invention is realized by the following technical scheme:
a preparation method of high-volume-fraction particle reinforced titanium-based composite material powder comprises the following steps:
s1, designing reinforced titanium-based composite material components, wherein the reinforced titanium-based composite material components comprise a matrix titanium alloy A, an intermediate alloy B and in-situ self-generated reaction additive particles C; wherein:
the intermediate alloy B is selected from one or more of Al-V alloy, Al-Mo alloy, Al-Nb alloy, Ti-Sn alloy, Al-Si alloy and Al-Sn alloy;
the in-situ self-generated reaction additive particles C are selected from TiB2、B4C. Carbon powder and LaB6One or more of Si powder;
s2, uniformly mixing the intermediate alloy B and the in-situ self-generated reaction adding particles C, wrapping the mixture into small blocks, uniformly placing the small blocks and the matrix alloy A in a mold together, and pressing the small blocks and the matrix alloy A into an electrode rod;
s3, carrying out vacuum consumable melting on the electrode bar to enable the matrix titanium alloy A, the intermediate alloy B and the in-situ self-generated reaction adding particles C to carry out in-situ reaction to obtain a high-volume-fraction particle reinforced titanium-based composite material ingot;
s4, heating and remelting the cast ingot serving as an electrode in a vacuum furnace to obtain high-volume particle reinforced titanium-based composite material melt, and preparing the melt into a rod for powder preparation through centrifugal casting;
s5, carrying out electrode induction melting and gas atomization on the bar to prepare powder, and obtaining the high-volume particle reinforced titanium-based composite material powder.
As another embodiment of the invention, a method for preparing high-volume-fraction particle reinforced titanium-based composite material powder comprises the following steps:
s1, designing reinforced titanium-based composite material components, wherein the reinforced titanium-based composite material components comprise a matrix titanium alloy A, an intermediate alloy B and in-situ self-generated reaction additive particles C; wherein:
the matrix titanium alloy A is sponge titanium;
the intermediate alloy B is selected from one or more of Al-V alloy, Al-Mo alloy, Al-Nb alloy, Ti-Sn alloy, Al-Si alloy and Al-Sn alloy;
the in-situ self-generated reaction additive particles C are selected from TiB2、B4C. Carbon powder and LaB6One or more of Si powder;
the components of the matrix titanium alloy A and one or more intermediate alloys B after being mixed meet the standard components of various titanium alloys such as Ti-6Al-4V, Ti600, TC21 and IMI 834;
the in-situ self-generated reaction additive particles C are selected from TiB2、B4C. Carbon powder and LaB6One or more of Si powder, added particles C and matrix alloy A undergo in-situ self-generated reaction to form a micron or nano particle reinforcement body, wherein the type of the micron or nano particle reinforcement body is TiB, TiC or La2O3And Ti5Si3And finally obtaining titanium-based composite material powder with uniformly distributed reinforcements, wherein the content of the reinforcements in the titanium-based composite material powder is 0.1-60%, and the volume fraction of the reinforcements comprises low content (0.1-10%) of reinforcements and high content (0: (a)>10%) reinforcement.
For the traditional titanium-based composite material, when the volume fraction of the reinforcement is more than 10%, a large number of reinforcements play an important bearing role, and simultaneously, crystal grains are refined, so that fine-grain reinforcement is realized, the strength of the material is greatly improved, but simultaneously, the introduction of a large number of reinforcements can limit the plastic deformation of a matrix, more interface defects, microcracks and the like can be induced, the plasticity of the material is greatly reduced, and the plastic deformation of a precise component is difficult to realize; the process flow can avoid the problem of deformation and cracking of the high volume fraction particle reinforced titanium-based composite material, and is particularly suitable for powder near-net forming of a particle reinforced titanium-based composite material precision component with a reinforcement volume fraction of more than 10%.
S2, uniformly mixing the intermediate alloy B and the in-situ self-generated reaction additive particles C, wrapping the mixture into small blocks by using aluminum foil, uniformly placing the small blocks and the matrix alloy A in a mold together, and pressing the small blocks and the matrix alloy A into an electrode rod;
s3, carrying out vacuum consumable melting on the electrode bar to enable the matrix titanium alloy A, the intermediate alloy B and the in-situ self-generated reaction adding particles C to carry out in-situ reaction to obtain a high-volume-fraction particle reinforced titanium-based composite material ingot;
s4, heating and remelting the cast ingot serving as an electrode in a vacuum furnace to obtain high-volume particle reinforced titanium-based composite material melt, pouring the high-volume particle reinforced titanium-based composite material melt into a mold, and preparing into a bar for milling through centrifugal casting;
s5, carrying out electrode induction melting and gas atomization on the bar to prepare powder, and obtaining the high-volume particle reinforced titanium-based composite material powder.
Step S4 specifically includes: and S3, mounting the cast ingot serving as an electrode in a vacuum skull furnace for heating and remelting, collecting the high-volume titanium-based composite material melt in a crucible, forming a layer of titanium-based composite material liquid skull with the thickness of 2.6-5 mm on the surface of a copper crucible serving as a protective layer, pouring the melt in the crucible into an electrode graphite mold, rotating the mold for centrifugation, and preparing a plurality of high-volume composite material rods for powder making through a centrifugal casting process.
In step S5, the specific steps of gas atomization milling are: and (4) welding the bar material obtained in the step (S4) serving as an electrode into an induction melting powder making device, heating and melting the bar material by using an induction coil, enabling the bar material to rotate and fall down gradually, breaking melt liquid drops under the impact of high-speed inert gas, and condensing the melt liquid drops into spherical powder.
In step S2, during the vacuum consumable melting, the vacuum degree is maintained at 1 × 10-2～1×10-3Pa。
In step S2, the size of the pressed electrode rod is a cylinder with an outer diameter of 100-250 mm and a length of 800-1200 mm.
In step S3, the number of vacuum consumable melting is at least two, and the melting current is 1-3 KA.
Preferably, in step S4, the melting current is 1.5KA to 3KA during the heating and remelting process in the vacuum skull melting furnace.
In the step S5, the electrode smelting temperature is 1700-2000 ℃, the atomizing pressure is 2.5-4 MPa, and the inert gas is argon gas in the induction smelting process.
The rotating speed of the centrifugal disc in the centrifugal casting process is 200-600 r/min.
The high-volume-fraction particle reinforced titanium-based composite material powder prepared by the preparation method also belongs to the protection scope of the invention.
As another embodiment of the invention, a preparation method of the high-volume-fraction particle reinforced titanium-based composite material powder comprises the following steps:
(1) designing titanium-based composite material components, uniformly mixing a matrix titanium alloy A, an intermediate alloy B and in-situ self-generated reaction adding particles C, wherein the intermediate alloy B and the in-situ self-generated reaction adding particles C are uniformly mixed according to a ratio, and are wrapped into small blocks, long blocks or lines by using aluminum foil, the small blocks, the long blocks or the lines and the matrix alloy A are uniformly placed in a mold together, mechanically pressing the small blocks and the long blocks or the lines into an electrode with a specified specification, carrying out vacuum self-consumption smelting for more than two times until the matrix, the intermediate alloy B and the in-situ self-generated reaction adding particles C are completely reacted in situ, obtaining a high-volume-fraction particle reinforced titanium-based composite material ingot, machining the titanium-based composite material ingot to remove surface defects, and machining to manufacture the titanium-based composite material ingot with the specified specification;
(2) installing the titanium-based composite material ingot in the step (1) as an electrode in a vacuum skull furnace for heating and remelting, collecting high-volume titanium-based composite material melt in a crucible, forming a titanium-based composite material liquid skull with the thickness of less than 5mm on the surface of a copper crucible as a protective layer, pouring the melt in the crucible into an electrode graphite mold, and rotating the mold to centrifugally prepare a plurality of high-volume composite material powder-making bars;
(3) taking the round bar material for powder making in the step (2) as an electrode, welding the round bar material in an induction melting powder making device, heating and melting the bar material by using an induction coil, enabling the bar material to rotate and fall down gradually, enabling melt liquid drops to be broken under the impact of high-speed inert gas, condensing the melt liquid drops into spherical powder, screening the powder with different particle sizes, and collecting the powder in a vacuum packaging bag according to the particle size range.
Preferably, the high-volume particle reinforced titanium-based composite material matrix can be selected from various titanium alloys such as pure titanium, Ti-6Al-4V, Ti60, Ti600, TC21, IMI834 and the like, and the type of the in-situ self-generated reaction added particles can be TiB2，B4C, carbon powder, LaB6Si powder and the like, the volume fraction of the reinforcement is 0.1-60%, and the types of the reinforcement generated in situ after smelting are TiB, TiC and La2O3And Ti5Si3And the like.
Preferably, the high volume fraction consumable electrode is a cylinder with an outer diameter of 200mm and a length of 1000 mm.
As a preferable scheme, in the vacuum consumable melting process, the current is adjusted according to the diameter of the cast ingot and the electrode feeding speed, the current range is 1 KA-3 KA, and the high-volume titanium-based composite material cast ingot is melted at least three times.
Preferably, in the remelting process of the vacuum skull furnace, the vacuum degree needs to be maintained at 1 × 10-2Pa～1×10-3Pa is between Pa.
Preferably, the pressure of the cooling water in the copper crucible is 0.4-1.0 MPa.
Preferably, the centrifugal casting process can be used for preparing 6-30 powder making bars with the specification of phi 50mm multiplied by 500mm at one time.
As the preferred scheme, the particle size standards of the screened powder in the atomization powder preparation process are respectively 0-50 um, 50-100 um, 100-150 um and powder above 150 um.
Preferably, the vacuum degree of the packaging tape for collecting the powder with different particle diameters is 5 multiplied by 10-1～1×10-1pa。
Compared with the prior art, the invention has the advantages that:
1. according to the invention, the vacuum skull furnace remelting and centrifugal casting are combined, so that the bar for milling the high-volume titanium-based composite material can be efficiently prepared in batches, the high-volume titanium-based composite material powder can be efficiently prepared, and the problems of cracking and complex process in the process of forging the high-volume particle reinforced titanium-based composite material ingot to prepare the bar for milling are solved.
2. The high volume fraction particle reinforced titanium-based composite material powder prepared by the invention can synthesize a high volume fraction reinforcement in situ in matrix alloy powder, and can remarkably improve the mechanical property of a member formed by the powder through additive manufacturing or powder metallurgy process.
3. The invention is suitable for preparing particle reinforced titanium-based composite material powder, and comprises TiB, TiC and La under pure titanium matrix, Ti-6Al-4V matrix, Ti60 matrix, Ti600 matrix and TC21 matrix IMI834 matrix2O3The Ti5Si3 reinforced composite material is suitable for the particle reinforced titanium-based composite material with the reinforcement content of 0-60 percent, in particular for the reinforced material with high body content (a)>10%) of titanium matrix composite. The high-volume titanium-based composite material powder prepared by the method can be suitable for additive manufacturing and powder metallurgy processes.
Drawings
In order to illustrate the features and advantages of the present invention more clearly, non-limiting embodiments will be described in detail below with reference to the accompanying drawings, in which:
FIG. 1 is a flow chart of the present invention, which includes powder preparation processes of preparing a high-volume particle reinforced Ti-based composite ingot, remelting in a vacuum skull furnace, centrifugal casting, and milling by induction melting;
FIG. 2 shows the powder distribution of a TiB reinforcement-containing titanium-based composite material of 30 vol.% with uniform powder distribution and similar particle size;
FIG. 3 is a titanium matrix composite powder structure containing 30 vol.% TiB reinforcement embedded in a matrix alloy powder;
fig. 4 shows the shape of the reinforcement inside the titanium-based composite powder containing 30 vol.% of TiB reinforcement, and it can be seen that the reinforcement is in the shape of needles and has a net distribution.
Detailed Description
The present invention will be described in detail with reference to examples. The following examples will help one skilled in the art to further understand the present invention, but not limit the present invention in any way, and it should be noted that one skilled in the art can make several variations and modifications without departing from the concept of the present invention, which fall within the protection scope of the present invention.
The invention provides high-volume-fraction particle reinforced titanium-based composite material powder and a preparation method thereof, wherein the preparation method of the high-volume-fraction particle reinforced titanium-based composite material comprises the following steps: designing reinforced titanium-based composite material components, wherein the reinforced titanium-based composite material components comprise a matrix titanium alloy A, an intermediate alloy B and in-situ self-generated reaction additive particles C; uniformly mixing the intermediate alloy B and the in-situ self-generated reaction additive particles C, and pressing into an electrode rod; carrying out vacuum consumable melting on the electrode bar to carry out in-situ reaction on the matrix titanium alloy A, the intermediate alloy B and the in-situ self-generated reaction additive particles C to obtain a high-volume-fraction particle reinforced titanium-based composite ingot; heating and remelting the cast ingot serving as an electrode in a vacuum furnace, pouring the cast ingot into a mold, and preparing a bar for powder making; and carrying out electrode induction melting and gas atomization on the bar to prepare powder, thus obtaining the high-volume-fraction particle reinforced titanium-based composite material powder.
FIG. 1 shows a flow chart of the present invention, which includes powder preparation processes of preparing high-volume particle reinforced Ti-based composite material ingot, remelting in a vacuum skull furnace, centrifugal casting and powder preparation by induction melting.
Example 1
Step one, adding granular boron carbide powder (B4C) serving as raw materials into matrix titanium alloy sponge titanium powder, intermediate alloy pure aluminum wires (Al) and aluminum vanadium alloy powder (Al-V) through in-situ self-generated reaction, weighing 2.5Kg of each part, wherein the sponge titanium powder, the pure aluminum wires and the aluminum vanadium alloy powder are proportioned according to Ti-6Al-4V alloy components, the mass fraction of the raw materials is 96.1%, the mass fraction of the boron carbide is 3.9%, the raw materials account for 150Kg, uniformly mixing the pure aluminum wires, the aluminum vanadium alloy powder and the boron carbide powder, wrapping the mixture into long strips by using aluminum foil, uniformly placing the long strips and the sponge titanium powder into a mold, and mechanically pressing the long strips into electrodes with the diameter of 200mm multiplied by 1000 mm.
Step two, the consumable electrode is arranged in a vacuum consumable arc furnace for smelting, the smelting current is controlled to be 2.5KA, and the vacuum degree is controlled to be 1 multiplied by 10-2Pa, taking the ingot obtained after smelting as an electrode to carry out next smelting, repeating the smelting process for three times to ensure that the components of the ingot are uniform, completely reacting the reinforcement with the matrix to obtain a third ingot, wherein the volume fraction of the (TiB + TiC) reinforcement in the ingot is 20%, machining the ingot to remove surface defects, and processing the ingot into an ingot with the outer diameter of 210mm and the length of 800 mm.
Step three, mounting the ingot obtained in the step two as an electrode in a vacuum arc skull-melting furnace for remelting, and controlling the melting current to be 2.5KA and the vacuum degree to be 1 multiplied by 10-2Pa, collecting the titanium-based composite material melt in a copper crucible, wherein the cooling water pressure of the copper crucible is 0.5MPa, the thickness of a skull on the surface of the crucible is 4mm, and collecting 125Kg of pure high-volume-fraction particle reinforced titanium-based composite material melt.
Step four, pouring the melt of the high-volume component obtained in the step three onto a casting device with a centrifugal disc, maintaining the vacuum degree in the step three at the rotating speed of 300 revolutions per minute, ensuring the complete mold filling, and obtaining 24 induction smelting powder making bars, wherein the outer diameter of each bar is 50mm, and the length of each bar is 500 mm.
And fifthly, welding the bar obtained in the fourth step on induction melting atomization equipment as an electrode, heating the bar to 1800 ℃ by using an induction coil, enabling the melt to freely flow downwards into a gas atomization furnace through a leakage hole, enabling the atomization pressure to be 4MPa, enabling the gas to be argon, crushing the high-volume-content titanium-based composite material melt into fine liquid drops, and rapidly cooling to obtain high-volume-content titanium-based composite material powder.
And step six, sieving the powder according to the particle size of the powder, wherein the particle size ranges of the powder are respectively 0-50 um, 50-100 um, 100-150 um and more than 150 um.
Seventhly, collecting, packaging and storing the powder with different particle sizes, wherein the vacuum degree of a packaging belt is 1 multiplied by 10-1pa。
Example 2
Firstly, carrying out in-situ self-generated reaction on matrix alloy titanium sponge powder, intermediate alloy aluminum niobium alloy powder (Al-Nb), titanium zinc alloy powder (Ti-Sn) and aluminum molybdenum alloy powder (Al-Mo) to add granular titanium diboride powder (TiB)2) Weighing 2.5kg of raw materials in parts, wherein the titanium sponge powder, the aluminum-niobium alloy powder, the titanium-zinc alloy powder and the aluminum-molybdenum alloy powder are proportioned according to IMI834 alloy components, the total mass fraction is 83.3%, the mass fraction of the titanium diboride powder is 17.7%, uniformly mixing the aluminum-niobium alloy powder, the titanium-zinc alloy powder, the aluminum-molybdenum alloy powder and the titanium diboride powder, wrapping the mixture into long strips by using aluminum foil, uniformly placing the strips and the titanium sponge in a mold together, and mechanically pressing to form the electrodes with the diameter of phi 200mm multiplied by 1000 mm.
Step two, the consumable electrode is arranged in a vacuum consumable arc furnace for smelting, the smelting current is controlled to be 2.5KA, and the vacuum degree is controlled to be 1 multiplied by 10-2Pa, taking the ingot obtained after smelting as an electrode to carry out next smelting, repeating the smelting process for three times to ensure that the components of the ingot are uniform, completely reacting the reinforcement with the matrix to obtain a third ingot, wherein the volume fraction of the TiB reinforcement in the ingot is 30%, machining the titanium-based composite ingot to remove surface defects, and machining the titanium-based composite ingot with the outer diameter of 210mm and the length of 800 mm.
Step three, mounting the tertiary ingot obtained in the step two as an electrode in a vacuum arc skull-melting furnace for remelting, and controlling the melting current to be 2.5KA and the vacuum degree to be 1 multiplied by 10-2Pa, collecting the titanium-based composite material melt in a copper crucible, wherein the cooling water pressure of the copper crucible is 0.5MPa, the thickness of a skull on the surface of the crucible is 4mm, and collecting 125Kg of pure high-volume particle reinforced titanium-based composite material melt.
Step four, pouring the melt of the high-volume component obtained in the step three into a pouring device with a centrifugal disc, maintaining the vacuum degree in the step three at the rotating speed of 250 revolutions per minute, ensuring the complete mold filling, and obtaining 24 induction smelting powder-making bars, wherein the outer diameter of each bar is 50mm, and the length of each bar is 500 mm.
And fifthly, welding the bar obtained in the fourth step on induction melting atomization equipment as an electrode, heating the bar to 1800 ℃ by using an induction coil, enabling the melt to freely flow downwards into a gas atomization furnace through a leakage hole, enabling the atomization pressure to be 4MPa, enabling the gas to be argon, crushing the high-volume-content titanium-based composite material melt into fine liquid drops, and rapidly cooling to obtain high-volume-content titanium-based composite material powder.
And step six, sieving the powder according to the particle size of the powder, wherein the particle size ranges of the powder are respectively 0-50 um, 50-100 um, 100-150 um and more than 150 um.
Seventhly, collecting, packaging and storing the powder with different particle sizes, wherein the vacuum degree of a packaging belt is 1 multiplied by 10-1pa。
FIG. 2 shows the powder distribution of 30 vol.% TiB reinforced Ti-based composite material prepared in this example, with a particle size of 50-100 um.
Fig. 3 and 4 show the internal micro-morphology and the distribution of the reinforcing members of the 30 vol.% TiB-reinforced ti-based composite powder prepared in this example, wherein the TiB reinforcing members are embedded in the IMI834 alloy powder and are distributed in a mesh shape.
Example 3
Taking the matrix alloy sponge titanium powder, the intermediate alloy of which is aluminum-molybdenum alloy powder (Al-Mo), aluminum-tin alloy powder (Al-Sn), zirconium powder (Zr), aluminum-iridium alloy powder (Al-Yi) and the in-situ self-generated reaction added granular silicon powder (Si) as raw materials, weighing 2.5kg of the raw materials, wherein the sponge titanium powder, the aluminum-molybdenum alloy powder, the aluminum-tin alloy powder, the zirconium powder and the aluminum-iridium alloy powder are proportioned according to Ti600 alloy components, the total mass fraction of the sponge titanium powder, the aluminum-molybdenum alloy powder, the aluminum-tin alloy powder, the zirconium powder and the aluminum-iridium alloy powder is 96.1 percent, the mass fraction of the silicon powder is 3.9 percent, uniformly mixing the aluminum-molybdenum alloy powder, the aluminum-tin alloy powder, the zirconium powder, the aluminum-iridium alloy powder and the silicon powder, uniformly wrapping the aluminum foil into long strips by using an aluminum foil, uniformly placing the long strips together with the sponge titanium, and mechanically pressing the electrodes with phi of 200mm multiplied by 1000 mm.
Step two, the consumable electrode is arranged in a vacuum consumable arc furnace for smelting, the smelting current is controlled to be 2.0KA, and the vacuum degree is controlled to be 1 multiplied by 10-2Pa, taking the ingot obtained after smelting as an electrode to carry out next smelting, repeating the smelting process for three times, ensuring that the components of the ingot are uniform, and completely reacting the reinforcement with the matrixObtaining three times of cast ingots and Ti in the cast ingots5Si3The volume fraction of the reinforcement is 15%, the titanium-based composite material ingot is machined to remove surface defects, and the titanium-based composite material ingot with the outer diameter of 210mm and the length of 800mm is processed.
Step three, mounting the tertiary ingot obtained in the step two as an electrode in a vacuum arc skull-melting furnace for remelting, and controlling the melting current to be 2.0KA and the vacuum degree to be 1 multiplied by 10-2Pa, collecting 105Kg of pure high-volume particle reinforced titanium-based composite material melt in a copper crucible, wherein the cooling water pressure of the copper crucible is 0.8MPa, the thickness of a skull on the surface of the crucible is 5 mm.
Step four, pouring the melt of the high part in the step three into a pouring device with a centrifugal disc, wherein the rotating speed of a mold is 300 revolutions per minute, the vacuum degree in the step three is maintained, the mold is ensured to be completely filled, 18 induction melting powder manufacturing rods are obtained, the outer diameter of each rod is 50mm, and the length of each rod is 500 mm.
And step five, welding the bar obtained in the step four on induction melting atomization equipment as an electrode, heating the bar to 1750 ℃ by using an induction coil, enabling the melt to freely flow downwards into a gas atomization furnace through a leakage hole, enabling the atomization pressure to be 3.5MPa, enabling the gas to adopt argon, crushing the high-volume-content titanium-based composite material melt into fine liquid drops, and rapidly cooling to obtain high-volume-content titanium-based composite material powder.
And step six, sieving the powder according to the particle size of the powder, wherein the particle size ranges of the powder are respectively 0-50 um, 50-100 um, 100-150 um and more than 150 um.
Seventhly, collecting, packaging and storing the powder with different particle sizes, wherein the vacuum degree of a packaging belt is 1 multiplied by 10-1pa。
Comparative example 1
This comparative example is essentially identical to the preparation of example 1, except that: after the tertiary titanium-based composite material ingot is prepared, the high-volume titanium-based composite material powder making bar is prepared by adopting a deformation forging post-machining mode, the ingot cracking phenomenon occurs in the deformation process, and the powder making failure caused by continuous deformation processing cannot be caused. The reason for this is that the introduction of high volume fraction reinforcement makes the plastic deformation capability of the cast ingot extremely poor, and it is difficult to continue to prepare the rod material for powder making.
Comparative example 2
This comparative example is essentially identical to the preparation of example 1, except that: in the vacuum shell-solidifying remelting and pouring processes, the cooling water pressure is 0.3MPa, so that the thickness of the solidified shell is less than 2.6mm, and the pouring failure or the low yield of the bar is caused. The reason is that the cooling speed is too low, so that the skull thickness is too low to cause the skull breaking and pollute the high-volume titanium-based composite material.
Comparative example 3
This comparative example is essentially identical to the preparation of example 1, except that: in the vacuum shell-condensing remelting and pouring process, the pressure of cooling water is 1.5MPa, and the thickness of the condensed shell is more than 5mm, so that the pouring is failed or the yield of the bar is low. Because the cooling speed is too high, the thickness of the solidified shell is too high, the melt material is wasted, the obtained melt is too little, and the sufficient powder-making bar is difficult to prepare at one time.
Comparative example 4
This comparative example is essentially identical to the preparation of example 1, except that: a graphite mould with a centrifugal disc is not adopted during pouring, so that when a pouring melt is solidified, the melt has too low fluidity and cannot be completely filled, and the prepared bar does not conform to the specified size or the surface defect is serious and cannot be used for powder preparation.
In conclusion, the invention provides a preparation method for efficiently preparing high-volume-fraction particle reinforced titanium-based composite material powder. The method comprises the following steps: firstly, smelting for more than two times by using a vacuum consumable electrode arc furnace to prepare a high-volume particle reinforced titanium-based composite ingot, and mechanically processing the high-volume particle reinforced titanium-based composite ingot with the surface of the ingot being a specified specification. Remelting a high-volume titanium-based composite material cast ingot in a vacuum skull furnace, pouring the titanium-based composite material melt in the remelted copper crucible into a casting mold with a centrifugal device, and obtaining more than 6 powder making bars at least at one time. Thirdly, using the high volume bar material as an electrode, melting the bar material by induction melting, using high-speed inert gas to impact and break melt liquid drops, forming fine spherical powder after condensation, collecting the high volume particle reinforced titanium-based composite material powder, and carrying out vacuum sealing. The method can efficiently prepare the high-volume particle reinforced titanium-based composite material powder, solves the problems of forging cracking and complicated powder preparation process caused by difficult deformation of the high-volume reinforcement, can efficiently prepare the high-volume particle reinforced titanium-based composite material powder, and has important engineering application value for laser additive manufacturing and powder metallurgy preparation of high-volume particle reinforced titanium-based composite material components.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention.
Claims (10)
1. A preparation method of high-volume-fraction particle reinforced titanium-based composite material powder is characterized by comprising the following steps:
s1, designing reinforced titanium-based composite material components, wherein the reinforced titanium-based composite material components comprise a matrix titanium alloy A, an intermediate alloy B and in-situ self-generated reaction additive particles C; wherein:
the intermediate alloy B is selected from one or more of Al-V alloy, Al-Mo alloy, Al-Nb alloy, Ti-Sn alloy, Al-Si alloy and Al-Sn alloy;
the in-situ self-generated reaction additive particles C are selected from TiB2、B4C. Carbon powder and LaB6One or more of Si powder;
s2, uniformly mixing the intermediate alloy B and the in-situ self-generated reaction adding particles C, wrapping the mixture into small blocks, uniformly placing the small blocks and the matrix titanium alloy A in a mold together, and pressing the small blocks and the matrix titanium alloy A into an electrode rod;
s3, carrying out vacuum consumable melting on the electrode bar to enable the matrix titanium alloy A, the intermediate alloy B and the in-situ self-generated reaction adding particles C to carry out in-situ reaction to obtain a high-volume-fraction particle reinforced titanium-based composite material ingot;
s4, heating and remelting the cast ingot serving as an electrode in a vacuum furnace to obtain high-volume particle reinforced titanium-based composite material melt, and preparing the melt into a rod for powder preparation through centrifugal casting;
s5, carrying out electrode induction melting and gas atomization on the bar to prepare powder, and obtaining the high-volume particle reinforced titanium-based composite material powder.
2. The method according to claim 1, wherein step S4 specifically comprises:
and S3, mounting the cast ingot serving as an electrode in a vacuum skull furnace for heating and remelting, collecting the high-volume titanium-based composite material melt in a crucible, forming a layer of titanium-based composite material liquid skull with the thickness of 2.6-5 mm on the surface of the crucible as a protective layer, pouring the melt in the crucible into an electrode graphite mold, rotating the mold for centrifugation, and preparing a plurality of high-volume composite material rods for powder making through a centrifugal casting process.
3. The method according to claim 2, wherein in step S4, the melting current is 1.5 KA-3 KA during the heating remelting process in the vacuum skull melting furnace.
4. The method of claim 1, wherein in step S5, the step of pulverizing by gas atomization comprises: and (4) welding the bar material obtained in the step (S4) serving as an electrode into an induction melting powder making device, heating and melting the bar material by using an induction coil, enabling the bar material to rotate and fall down gradually, breaking melt liquid drops under the impact of high-speed inert gas, and condensing the melt liquid drops into spherical powder.
5. The method of claim 1, wherein in step S3, during the vacuum consumable melting process, the vacuum degree is maintained at 1 x 10-2～1×10-3Pa。
6. The method according to claim 1, wherein in step S2, the pressed electrode rod has a cylindrical shape with an outer diameter of 100 to 250mm and a length of 800 to 1200 mm.
7. The preparation method of claim 1, wherein in step S3, the number of vacuum consumable melting times is at least two, and the melting current is 1-3 KA.
8. The preparation method of claim 1, wherein in step S5, the electrode melting temperature is 1700-2000 ℃, the atomization pressure is 2.5-4 MPa, and the inert gas is argon gas.
9. The method according to claim 1, wherein the rotation speed of the centrifugal disk during the centrifugal casting is 200-600 rpm.
10. A high-volume-fraction particle-reinforced titanium-based composite powder prepared by the preparation method according to any one of claims 1 to 9.
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