CN105648303B - It is a kind of to improve the method that atomization prepares powder of stainless steel sphericity - Google Patents
It is a kind of to improve the method that atomization prepares powder of stainless steel sphericity Download PDFInfo
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- CN105648303B CN105648303B CN201610118170.9A CN201610118170A CN105648303B CN 105648303 B CN105648303 B CN 105648303B CN 201610118170 A CN201610118170 A CN 201610118170A CN 105648303 B CN105648303 B CN 105648303B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
- C22C33/06—Making ferrous alloys by melting using master alloys
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y70/00—Materials specially adapted for additive manufacturing
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Abstract
The method that atomization prepares powder of stainless steel sphericity is improved the invention discloses a kind of, by reducing the oxygen that in stainless steel surface tension can reduce, the content of the element such as nitrogen and sulphur, control can make the content of the elemental silicon of surface tension increase in the target stainless steel standard composition upper limit, and add the micronutrient boron that can increase surface tension, so that significantly improving the surface tension of stainless steel melt drop on the basis of stainless Steel Properties are not influenceed, stainless steel melt drop is set to be shrunk to the more preferable powder of sphericity under bigger surface tension effects in atomization, realize and improve the purpose that atomization prepares powder of stainless steel sphericity.
Description
Technical field
The 3D printing method of powder of stainless steel sphericity is prepared the present invention relates to a kind of raising atomization, belongs to 3D printing
Material and field of powder metallurgy.
Background technology
Atomization is the common method for preparing metal dust, mainly including aerosolization, water atomization, centrifugal atomizing, ultrasonic mist
Change, plasma atomization etc..In general, the pattern of the metal dust prepared by different atomizations is distinguishing.Water smoke
Being in irregular shape, the poor fluidity of powder the pattern for the metal dust for changing preparation more；And aerosolization, centrifugal atomizing, ultrasonic mist
The atomizations such as change, plasma atomization can prepare spherical or subsphaeroidal powder, and the mobility of powder is preferable.
3D printing（Increasing material manufacturing）Refer to, according to mathematical model, be superimposed by continuous physical layer, successively increase material
Mode manufactures the technology of 3D solid object, represents the new trend of world's development of manufacturing.At present, the gold industrially applied
Raw material used in category 3D printing are mainly all kinds of metal dusts, automatic powder feeding system master used in these metal 3D printing techniques
There are powder bed powdering and the major class of coaxial powder-feeding two.In order to ensure the continuity and high accuracy of print procedure, it is required to be used
The sphericity of metal dust is high, with splendid mobility.
Powder of stainless steel is the important raw material of a class used in 3D printing.At present, powder of stainless steel can by water atomization,
Prepared by aerosolization or plasma atomization, such as, and patent CN201010574595.3 discloses a kind of hydraulic atomized method production ball
The method of shape stainless steel powder powder material；Patent CN200710121435.1 discloses one kind and prepares nitrogenous/height using gas atomization
The method of nitrogen stainless steel powder；Patent CN201310304846.X discloses a kind of plasma spheroidization and prepares minute spherical stainless steel
The method of powder.But the difference of the above method is that used atomization method is different, and prepared powder of stainless steel is directed to
Traditional powder metallurgy or the application of metal injection molded field, the sphericity and mobility of powder can't fully meet 3D printing
Particular/special requirement.
The content of the invention
The invention aims to provide it is a kind of can further improve the method that atomization prepares powder of stainless steel sphericity,
So that the sphericity and mobile performance of prepared powder of stainless steel meet the use requirement of 3D printing.
Realize that the technical scheme method of the object of the invention is as follows：A kind of raising atomization prepares powder of stainless steel sphericity
Method, comprises the following steps：
The first step：First, raw material is matched according to the standard analysis of target stainless steel, heats fused raw material and carry out
Deoxidation, denitrogenation, desulfurization process, wherein, deoxidation is used adds the progress of silicomanganese calcium aluminium barium double deoxidizer, its addition in molten steel
No more than the 0.1% of molten steel gross mass；Denitrogenation is carried out using the one or more in a certain amount of Ti, Al, V are added in molten steel,
Maxima solubility 0.045% and molten steel total amount of the specific addition foundation nitrogen in molten steel are calculated and determined；Desulfurization is used in molten steel
Add the composite desulfurizing agent containing Ca, Al to carry out, consumption is the 0.3% of molten steel gross mass, that is, obtain oxygen, nitrogen, sulfur content and be below
100ppm hypoxemia, low nitrogen, low-sulfur stainless steel foundry alloy；
Second step：Hypoxemia that the first step is obtained, low nitrogen, low-sulfur stainless steel foundry alloy remelting, determine and control female conjunction
The content of silicon in gold, determines that silicone content reaches the interval upper limit of target stainless steel standard composition, meanwhile, micro boron is added, its
Addition not form the precipitate of boracic on target stainless steel base as the upper limit so that obtain the hypoxemia of siliceous and boron, it is low
Nitrogen, low-sulfur stainless steel foundry alloy；
3rd step：Stainless steel foundry alloy prepared by second step carries out powder by atomization.
Further, in the first step, silicomanganese calcium aluminium barium double deoxidizer is 40wt%Si, 10wt%Mn, 25wt%Ca, 10wt%
Al, 15wt%Ba composition.
Further, in the first step, composite desulfurizing agent is 60wt%CaC2、20wt%CaO 、10wt%CaF2, 10wt%Al
Composition.
Further, in the 3rd step, powder by atomization includes water atomization, aerosolization, centrifugal atomizing, ultrasonic atomizatio, plasma
Body atomization, it is rotating electrode atomized.
Compared with prior art, it is an advantage of the invention that：
1st, surface tension of the present invention to increase stainless steel melt drop has carried out special design to its composition as target
And adjustment, improved stainless steel melt drop surface tension it is bigger than corresponding standard brand stainless steel surfaces tension force, because
And sphericity and mobility more preferably powder of stainless steel can be obtained under identical atomization process and atomization plant, it disclosure satisfy that 3D
The particular/special requirement of printing.
2nd, the method for the invention is simple, and be significantly improved effect to existing powder by atomization technology.
Brief description of the drawings
Fig. 1 is the SEM figures of the powder of stainless steel of aerosolization 430 prepared using the inventive method.
Fig. 2 is the SEM figures of the aerosolization 316L powder of stainless steel prepared using the inventive method.
Embodiment
The principle of institute's foundation of the present invention is by adjusting impurity element larger to effect of surface tension in stainless steel and micro-
The content of nonmetalloid is measured, further the surface tension of increase stainless steel melt drop, so that stainless steel melt drop exists
Sphericity more preferable powder can be shrunk to during atomization under bigger surface tension effects.For that can be made by reducing in stainless steel
The content of the elements such as oxygen, nitrogen and the sulphur that surface tension reduces, meanwhile, control can make the content of the elemental silicon of surface tension increase exist
Capping in allowed band, and add the micro element boron that can increase surface tension；Adjusted by mentioned component, in not shadow
The surface tension of stainless steel melt drop is significantly improved on the basis of the stainless Steel Properties of sound, makes stainless steel melt drop in atomization
The more preferable powder of sphericity can be shrunk under bigger surface tension effects, realizes that improving atomization prepares powder of stainless steel
The purpose of sphericity.
The method that a kind of raising atomization of the present invention prepares powder of stainless steel sphericity, comprises the following steps：
The first step：The purpose of the step is to reduce the oxygen that in stainless steel foundry alloy surface tension can reduce, nitrogen as far as possible
With the content of the element such as sulphur, but for nitrogenous stainless steel then to reduce the content of oxygen and sulphur as target.First, according to required system
The standard chemical composition of the standby target stainless steel trade mark is matched, and heating melts and carries out deoxidation, denitrogenation, desulfurization process（Adopt
Carried out with the deoxidation in traditional process for making, denitrogenation, sulfur removal technology）, wherein, deoxidation is used adds silicomanganese calcium aluminium in molten steel
Barium double deoxidizer（Addition is no more than the 0.1% of molten steel total amount）Precipitation desoxydation method carry out；Denitrogenation uses in molten steel and adds one
One or more in quantitative Ti, Al, V are carried out（Maxima solubility of the specific addition according to nitrogen in molten steel
（0.045%）Calculate and determine with molten steel total amount, such as 100 kilograms molten steel addition Ti 150g）；Desulfurization, which uses to add in molten steel, to be contained
The composite desulfurizing agent of Ca, Al oxide（CaC2 60%+CaO 20%+CaF210%+Al 10%, consumption is the 0.3% of molten steel total amount）
Carry out；So as to obtain hypoxemia, low nitrogen, low-sulfur stainless steel foundry alloy.In order to reach the content of reduction oxygen, nitrogen, element sulphur as far as possible
（The content of each element is less than 100ppm）, the deoxidation that is used, denitrogenation, desulfurization process means include but is not limited to listed above
Method.
Second step：Hypoxemia that the first step is obtained, low nitrogen, low-sulfur stainless steel foundry alloy remelting, determine and control female conjunction
The content of silicon in gold（It is general to use ICP or Photometric Determination）For the upper limit that the composition of standard analysis defined is interval, such as
Less than higher limit, then appropriate silicon is added again to the interval upper limit of composition.Meanwhile, add micro boron, addition with it is prepared not
The difference of the rust steel trade mark slightly has difference（Because solubility of the boron element in the stainless steel of heterogeneity is variant）, but with not
The precipitate for not forming boracic in rust steel matrix is the upper limit（Maxima solubility of the higher limit by boron element in the composition stainless steel
Determine, solubility of the boron in stainless steel is usually no more than 0.03%）, so as to obtain the hypoxemia of siliceous and boron, low nitrogen, low-sulfur not
Become rusty steel foundry alloy.
3rd step：The prepared hypoxemia containing appropriate silicon and boron, low nitrogen, low-sulfur stainless steel foundry alloy are subjected to atomization system
Powder, can prepare metal using water atomization, aerosolization, centrifugal atomizing, ultrasonic atomizatio, plasma atomization, rotating electrode atomized etc.
The atomization of powder is carried out.Because invention increases the surface tension of stainless steel melt itself, therefore, it improves prepared
The effect of the sphericity of powder is not rely on specific atomization.
Embodiment 1
Prepare spherical 430 powder of stainless steel.
（1）According to the standard analysis of 430 stainless steels（C:≤ 0.12%, Si:≤ 0.75%, Mn:≤ 1.00%, P:≤
0.040%, S:≤ 0.030%, Ni:≤ 0.60%, Cr:16.00~18.00%；Surplus is iron；Mass percent, raw metal purity
For more than 99.9%）Matched, the consumption of each raw material is determined in mentioned component ratio and the total amount of prepared stainless steel,
In the present embodiment, the stainless steels of 100kg 430 are prepared, each element consumption is as follows：Cr 18kg, Ni 0.6kg, Mn 1kg, Si
0.75kg, surplus is Fe, and C, P and S content are no more than standard analysis requirement；Heating melting, adds 0.1kg silicomanganese calcium in molten steel
Aluminium barium double deoxidizer carries out precipitation desoxydation, and 150 g Ti are added in molten steel and carry out denitrogenation, and 0.3 kg is added in molten steel and is answered
Close desulfurizing agent (CaC2 60%+CaO 20%+CaF210%+Al 10%) desulfurization is carried out, so that it is stainless to obtain hypoxemia, low nitrogen, low-sulfur
Steel foundry alloy.
（2）By prepared stainless steel foundry alloy remelting, determined using ICP and control the content of silicon 430 stainless steels into
The upper limit in the permission interval divided, i.e., 0.75% (being 0.75 kg in mass fraction, this example)；Addition 0.03% boron (mass fraction,
It is 0.03 kg in this example), so as to obtain the hypoxemia containing appropriate silicon and boron, low nitrogen, low-sulfur stainless steel foundry alloy.
（3）The prepared hypoxemia containing appropriate silicon and boron, low nitrogen, the stainless steel foundry alloy of low-sulfur 430 are subjected to aerosolization system
Powder, atomization gas is argon gas, and gas pressure intensity is 6MPa, so as to obtain 430 powder of stainless steel, as shown in Figure 1, it is seen then that used
The sphericity of 430 powder of stainless steel prepared by the inventive method is splendid, substantially without hollow powder and satellite ball phenomenon, good fluidity,
It disclosure satisfy that the use demand of 3D printing.
Embodiment 2
Prepare spherical 316L powder of stainless steel.
（1）According to the standard analysis of 316L stainless steels（C：≤ 0.030%, Si：≤ 1.00%, Mn：≤ 2.00%, S：≤
0.030%, P：≤ 0.045%, Cr：16.00~18.00%, Ni：10.00~14.00%, Mo：2.00~3.0%, quality percentage
Than raw metal purity is more than 99.9%）Matched, the consumptions of each raw material in mentioned component ratio and it is prepared not
The total amount of rust steel is determined, in the present embodiment, prepares 100kg 316L stainless steels, and each element consumption is as follows：Cr 18kg, Ni
14kg, Mn 2kg, Mo 3kg, Si 1kg, surplus are Fe, and C, P and S content are no more than standard analysis requirement；Heating melting, in steel
0.1kg silicomanganese calcium aluminium composite deoxidant is added in liquid and carries out precipitation desoxydation, 150 g Ti are added in molten steel and carry out denitrogenation, in steel
0.3 kg composite desulfurizing agents (CaC is added in liquid2 60%+CaO 20%+CaF210%+Al 10%) desulfurization is carried out, so as to obtain
Hypoxemia, low nitrogen, low-sulfur stainless steel foundry alloy.
（2）By prepared stainless steel foundry alloy remelting, determined using ICP and control the content of silicon 316L stainless steels into
Divide the upper limit of allowed band, i.e., 1%（It is 1 kg in mass fraction, this example)）；Addition 0.026%（It is in mass fraction, this example
0.026kg）Boron, so as to obtain the hypoxemia containing appropriate silicon and boron, low nitrogen, low-sulfur stainless steel foundry alloy.
（3）The prepared hypoxemia containing appropriate silicon and boron, low nitrogen, low-sulfur 316L stainless steels foundry alloy are subjected to aerosolization system
Powder, atomization gas is argon gas, and gas pressure intensity is 6MPa, so as to obtain 316L powder of stainless steel, as shown in Figure 2, it can be seen that
The sphericity of the 316L powder of stainless steel prepared using the inventive method is splendid, no hollow powder and satellite ball phenomenon, mobility pole
It is good, it disclosure satisfy that the use demand of 3D printing.
Claims (4)
1. a kind of improve the method that atomization prepares powder of stainless steel sphericity, it is characterised in that comprises the following steps：
The first step：Raw material is matched according to the standard analysis of target stainless steel, fused raw material is heated and carries out deoxidation, takes off
Nitrogen, desulfurization process, wherein, deoxidation is used adds the progress of silicomanganese calcium aluminium barium double deoxidizer in molten steel, and its addition is no more than
The 0.1% of molten steel gross mass；Denitrogenation is carried out using the one or more in a certain amount of Ti, Al, V are added in molten steel, and it is added
Maxima solubility 0.045% and molten steel total amount of the amount foundation nitrogen in molten steel are calculated and determined；Desulfurization, which uses to add in molten steel, to be contained
Ca, Al composite desulfurizing agent are carried out, and consumption is the 0.3% of molten steel gross mass, that is, are obtained oxygen, nitrogen, sulfur content and be below 100ppm's
Hypoxemia, low nitrogen, low-sulfur stainless steel foundry alloy；
Second step：Hypoxemia that the first step is obtained, low nitrogen, low-sulfur stainless steel foundry alloy remelting, determine and control in foundry alloy
The content of silicon, determines that silicone content reaches the interval upper limit of target stainless steel standard composition, meanwhile, micro boron is added, it is added
Measure not form the precipitate of boracic on target stainless steel base as the upper limit, thus obtain the hypoxemia of siliceous and boron, it is low nitrogen, low
Sulphur stainless steel foundry alloy；
3rd step：Stainless steel foundry alloy prepared by second step carries out powder by atomization.
2. the method that atomization prepares powder of stainless steel sphericity is improved as claimed in claim 1, it is characterised in that the first step
In, silicomanganese calcium aluminium barium double deoxidizer is 40wt%Si, 10wt%Mn, 25wt%Ca, 10wt%Al, 15wt%Ba composition.
3. the method that atomization prepares powder of stainless steel sphericity is improved as claimed in claim 1, it is characterised in that the first step
In, composite desulfurizing agent is 60wt%CaC2、20wt%CaO 、10wt%CaF2, 10wt%Al composition.
4. the method that atomization prepares powder of stainless steel sphericity is improved as claimed in claim 1, it is characterised in that the 3rd step
In, powder by atomization include water atomization, aerosolization, centrifugal atomizing, ultrasonic atomizatio, plasma atomization, it is rotating electrode atomized.
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| US20180104745A1 (en) * | 2016-10-17 | 2018-04-19 | Ecole Polytechnique | Treatment of melt for atomization technology |
| CN107999774B (en) * | 2017-12-05 | 2021-01-26 | 南通金源智能技术有限公司 | Method for improving sphericity of 3D printed stainless steel powder |
| CN112620642A (en) * | 2020-12-29 | 2021-04-09 | 深圳市福英达工业技术有限公司 | Centrifugal atomization device and method for preparing high-temperature high-surface-tension metal powder |
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| JPS5852521B2 (en) * | 1979-05-10 | 1983-11-24 | 大同特殊鋼株式会社 | spherical stainless steel powder |
| CN100513019C (en) * | 2007-09-06 | 2009-07-15 | 安泰科技股份有限公司 | Method for producing stainless steel powder containing nitrogen high nitrogen by adopting gas atomization method |
| CN101671762A (en) * | 2008-09-11 | 2010-03-17 | 北大方正集团有限公司 | Production method for medium and low alloy special steel |
| CN101381868A (en) * | 2008-10-27 | 2009-03-11 | 徐洪 | High-hardness stainless steel alloy powder for laser remelted and technique of preparing the same |
| CN102350497B (en) * | 2011-09-16 | 2013-02-06 | 中南大学 | High-compressibility water atomization iron powder and preparation method thereof |
| CN103111625A (en) * | 2013-03-19 | 2013-05-22 | 南京理工大学 | Method of improving sphericity degree of metal powder prepared through water atomization |
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