WO2016119556A1 - 一种用于3d打印的铝粉及其制备方法 - Google Patents

一种用于3d打印的铝粉及其制备方法 Download PDF

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WO2016119556A1
WO2016119556A1 PCT/CN2015/099659 CN2015099659W WO2016119556A1 WO 2016119556 A1 WO2016119556 A1 WO 2016119556A1 CN 2015099659 W CN2015099659 W CN 2015099659W WO 2016119556 A1 WO2016119556 A1 WO 2016119556A1
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aluminum powder
aluminum
carbon black
printing
white carbon
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PCT/CN2015/099659
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English (en)
French (fr)
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陈庆
曾军堂
叶任海
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成都新柯力化工科技有限公司
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Publication of WO2016119556A1 publication Critical patent/WO2016119556A1/zh

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • B22F1/102Metallic powder coated with organic material
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00Making metallic powder or suspensions thereof
    • B22F9/02Making metallic powder or suspensions thereof using physical processes
    • B22F9/04Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling

Definitions

  • the present invention belongs to the field of 3D printing manufacturing, and in particular relates to an aluminum powder for 3D printing manufacturing, and further relates to a method for preparing the aluminum powder.
  • 3D printing technology is a rapid additive manufacturing technology that generates three-dimensional solids by adding stacked materials layer by layer, which not only overcomes the loss caused by traditional material reduction, but also makes the product manufacturing more intelligent, more precise and more efficient. .
  • 3D printing technology shows great advantages.
  • 3D printing technology is a high-tech manufacturing technology with industrial revolution significance. It represents a new trend in the world's manufacturing industry and plays an important role in accelerating the development of advanced manufacturing industry and promoting industrial transformation and upgrading. With the development of high-end manufacturing, 3D printing manufacturing technology is currently highly concerned, and together with robot technology and artificial intelligence technology, it is called the key technology to promote the third industrial revolution.
  • the material bottleneck becomes a problem that restricts the development of 3D printing, and is also the key point and difficulty of the breakthrough innovation of 3D printing.
  • the material commonly used in 3D printing technology is a plastic material, which is extruded from the nozzle in a molten state by the thermoplastic meltability of the plastic material, and finally forms a product by superposition of the solidified layer. Due to the good thermal flow of plastic materials, rapid cooling adhesion, and high mechanical strength, it has been rapidly applied and developed in the field of 3D printing manufacturing. The final development of 3D printing is in high-end industrial applications. Resin plastics cannot meet the needs of high-end industrial 3D printing. Therefore, 3D printing materials are gradually developing from resin plastics to metal materials.
  • metal powder mainly uses a high-power energy beam such as a laser or an electron beam as a heat source to melt the selected material, and after cooling and crystallization, a stacked layer is continuously formed to form a final product. Due to the high melting temperature of the metal powder, it is easy to oxidize, affecting the strength of the product, and the solidification of the material after laser melting causes the volume of the metal to shrink, causing huge thermal stress of the material and seriously affecting the strength of the material. In addition, due to the influence of the particle size and distribution of the metal powder, the cooling crystallization process is complicated, and the crystallization process is difficult to quantitatively control. Once the crystal coarse, dendrites, etc. appear, the mechanical properties of the material after molding will be reduced. The end result is that the key components are not available for practical use.
  • a high-power energy beam such as a laser or an electron beam
  • Cimbo patent CN103862040A discloses a magnesium-based metal powder material for 3D printing, which is composed of magnesium powder wrapped with rosin coating as a basic material, nickel powder wrapped with rosin film as a supporting material, and aluminum powder as an intermediate material. , by mixing and mixing. In order to obtain a high strength alloy device, a plurality of methods of metal blending are employed.
  • Chinese invention patent CN103801704A discloses a copper powder for 3D printing, which uses an argon gas protection furnace to melt TU0 oxygen-free copper to 1250 ⁇ 1400 ° C, and removes inclusions in the molten copper liquid by blowing argon at the bottom of the furnace.
  • the copper solution is completely melted and the temperature is uniform.
  • the leakage of the enthalpy and the flow nozzle through the gas atomizing nozzle to form small droplets, the obtained copper powder is spherical, but the particle size is large, so the melting temperature is high and difficult to control when used for 3D printing.
  • metal powders currently used in 3D printing manufacturing have problems such as high melting temperature, large particle size, high oxygen content, poor sphericity, poor composition uniformity, and poor particle size distribution. Therefore, the metal powder is uneven in thickness and uneven in melting, which causes volume shrinkage during solidification, resulting in structural defects and strength damage.
  • 3D printed metal powders have defects of coarse particle size, uneven distribution, high oxygen content, and high melting temperature.
  • the present invention proposes an aluminum powder for 3D printing.
  • the aluminum powder is made of silica as a carrier. Under vacuum conditions, aluminum is melted in 68CTC, and stays in the gap of white carbon black.
  • the spherical aluminum powder is formed by argon gas protection to reduce the oxygen content of the spherical aluminum powder.
  • the aluminum powder is coated and polymerized on the surface of the aluminum powder, so that the aluminum powder is used for 3D printing. Further, a preparation method for 3D printed aluminum powder is provided.
  • An aluminum powder for 3D printing characterized in that: with white carbon black as a carrier, the mass ratio of white carbon black to aluminum is 1:300-500, and the aluminum aluminum melts in the white carbon black In the void, a spherical aluminum powder having an average particle diameter of 50-100 nm and a sphericity of 0.75 or more is obtained by grinding and refining, and the spherical aluminum powder is coated with a monomer and polymerized. Can be used in 3D printing manufacturing.
  • the silica has a pore diameter of 100 to 150 nm.
  • the monomer is at least one of acrylate, methacrylate, and styrene.
  • a method for preparing aluminum powder for 3D printing according to the present invention is characterized in that:
  • [0015] 2 After cooling the molten aluminum-silica composite obtained in the step 1), it is ground under the protection of argon, and the pore diameter of 100-150 nm of silica is used as the separator for granulating the aluminum powder, which is not only easy. Grinding and pulverizing dispersion, and the obtained aluminum powder has a uniform particle size distribution and a low oxygen content;
  • step 2) 100 parts by weight of the aluminum powder obtained in step 2), 0. 5-1. 0 parts by weight of the monomer was added to the reaction mixer, the temperature was raised to 80-120 ° C, high-speed stirring at 400-900 rpm Disperse for 15-20 minutes, then add 0. 008- 0. 01 parts by weight of the initiator, the monomer is at least one of acrylate, methacrylate, styrene, and the initiator is selected as 2 , 3-diphenylbutyronitrile, under the action of an initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain an aluminum powder for 3D printing.
  • the invention relates to an aluminum powder for 3D printing, which is used as a separator for granulating aluminum powder through a pore size of 100-150 nm of white carbon black, so that the aluminum powder is easy to be ground and pulverized, and the obtained aluminum powder is nanometer-sized, and the particle size is The distribution is uniform, and the sphericity is 0.75 or more.
  • a liquid monomer is dispersed, and the surface of the aluminum powder is coated and polymerized.
  • the obtained aluminum powder has low melting temperature and uniform melting, is used for uniform internal structure of metal in 3D printing manufacturing, and has improved product forming precision, and can be used for preparing precision metal products of complicated components; the surface of aluminum powder is coated with a thin layer of adhesive by polymerization. Effectively prevent oxidation, so that aluminum powder is used in 3D printing to produce a polymer with high fluidity and good thermal bond formability, oxygen content less than 323 ppm, and surface coating of aluminum powder at 135 ° C or lower. Melt and wet the aluminum powder particles for low temperature printing.
  • the present invention relates to an aluminum powder for 3D printing and a preparation method thereof, and the outstanding features and excellent effects thereof are compared with the prior art:
  • the aluminum powder for 3D printing of the present invention using white carbon black as a carrier, having an average particle diameter of 50-100 nm, The sphericity is 0.75 or more, and the spherical aluminum powder is coated with a monomer and polymerized, and can be used for 3D printing.
  • the aluminum powder for 3D printing of the invention has a particle size of nanometer size and uniform particle size distribution, so the melting temperature is low and the melting is uniform, and the metal internal organization is uniform during 3D printing manufacturing, and the product forming precision is Improved, can be used to prepare precision metal parts for complex components.
  • the aluminum powder for 3D printing of the present invention the surface of the aluminum powder is coated with a thin layer of adhesive to effectively prevent oxidation, so that the aluminum powder is used for 3D printing and has high fluidity and good Thermal bond formability
  • a method for preparing aluminum powder for 3D printing according to the present invention wherein a pore size of 100-150 nm of silica is used as a separator for granulating aluminum powder, so that the aluminum powder is easily ground and pulverized, and the obtained aluminum powder is obtained.
  • the diameter distribution is uniform and the sphericity is high.
  • the surface of the aluminum powder is coated and polymerized by the monomer, the coating is complete, and the coating layer is thin, which greatly reduces the influence of the adhesive on the strength of the metal product.
  • [0025] 2 After cooling the molten aluminum-silica composite obtained in the step 1), grinding is performed under the protection of argon, and the pore size of 100-150 nm of silica is used as the separator for granulating the aluminum powder, which is not only easy. Grinding and pulverizing dispersion, and the obtained aluminum powder has a uniform particle size distribution and a low oxygen content;
  • step 2) The aluminum powder obtained in step 2) 100 parts by weight, 0.5 parts by weight of acrylate was added to the reaction mixer, the temperature was raised to 80 ° C, dispersed at high speed stirring of 400 rpm for 15 minutes, and then added 0. 008 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the acrylate polymerizes on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a 3D printing.
  • Aluminum powder 100 parts by weight, 0.5 parts by weight of acrylate was added to the reaction mixer, the temperature was raised to 80 ° C, dispersed at high speed stirring of 400 rpm for 15 minutes, and then added 0. 008 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the acrylate polymerizes on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a 3D printing.
  • the polymer coated on the surface of the aluminum powder is melted and infiltrated with aluminum powder particles at 125 ° C, and after cooling and solidification, the aluminum powder particles are bonded to form a metal crucible, and after sintering, The polymer is decomposed and the aluminum powder is gradually melted and solidified to form an aluminum metal member. Since the aluminum powder has a small particle size and a uniform distribution, the melting temperature is low and the melting is uniform, and the internal structure of the metal aluminum member is uniform during the 3D printing manufacturing, and the molding precision of the product is improved.
  • [0031] 2 After cooling the molten aluminum-silica composite obtained in the step 1), grinding is performed under the protection of argon gas, and the pore diameter of 100-150 nm of silica is used as a separator for granulating the aluminum powder, which is not only easy. Grinding and pulverizing dispersion, and the obtained aluminum powder has a uniform particle size distribution and a low oxygen content;
  • step 2 100 parts by weight of the aluminum powder obtained in step 2), 0.5 parts by weight of methacrylate was added to the reaction mixer, the temperature was raised to 80 ° C, dispersed at 900 rpm for 20 minutes, then added 0. 01 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a kind for 3D.
  • Printed aluminum powder [0033] The aluminum powder obtained in Example 2 was tested by pass: The performance data is as follows:
  • Printing is performed through the nozzle of the 3D printer, and the polymer coated on the surface of the aluminum powder is melted and infiltrated with aluminum powder particles at 135 ° C. After cooling and solidification, the aluminum powder particles are bonded to form a metal crucible, and after sintering, The polymer is decomposed and the aluminum powder is gradually melted and solidified to form an aluminum metal member. Since the aluminum powder has a small particle size and a uniform distribution, the melting temperature is low and the melting is uniform, and the internal structure of the metal aluminum member is uniform during the 3D printing manufacturing, and the molding precision of the product is improved.
  • [0037] 2 After cooling the molten aluminum-silica composite obtained in the step 1), grinding is performed under the protection of argon, and the pore diameter of 100-150 nm of silica is used as the separator for granulating the aluminum powder, which is not only easy. Grinding and pulverizing dispersion, and the obtained aluminum powder has a uniform particle size distribution and a low oxygen content;
  • step 2) The aluminum powder obtained in step 2) 100 parts by weight, 0.5 parts by weight of styrene was added to the reaction mixer, the temperature was raised to 100 ° C, dispersed at high speed stirring of 400 rpm for 15 minutes, and then added 0. 01 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a 3D printing.
  • Aluminum powder 100 parts by weight, 0.5 parts by weight of styrene was added to the reaction mixer, the temperature was raised to 100 ° C, dispersed at high speed stirring of 400 rpm for 15 minutes, and then added 0. 01 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a 3D printing.
  • the polymer coated on the surface of the aluminum powder is melted and impregnated with aluminum powder particles at 115 ° C, and after cooling and solidification, the aluminum powder particles are bonded to form a metal crucible, and after sintering, The polymer is decomposed and the aluminum powder is gradually melted and solidified to form an aluminum metal member. Since the aluminum powder has a small particle size and a uniform distribution, the melting temperature is low and the melting is uniform, and the internal structure of the metal aluminum member is uniform during the 3D printing manufacturing, and the molding precision of the product is improved.
  • [0043] 2 After cooling the molten aluminum-silica composite obtained in the step 1), grinding is performed under the protection of argon gas, and the pore diameter of 100-150 nm of silica is used as the separator for granulating the aluminum powder, which is not only easy. Grinding and pulverizing dispersion, and the obtained aluminum powder has a uniform particle size distribution and a low oxygen content;
  • step 2) 100 parts by weight of the aluminum powder obtained in step 2), 0.8 parts by weight of methacrylate was added to the reaction mixer, the temperature was raised to 120 ° C, dispersed at 800 rpm for 18 minutes, then added 0. 008 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a kind for 3D.
  • Printed aluminum powder 100 parts by weight of the aluminum powder obtained in step 2), 0.8 parts by weight of methacrylate was added to the reaction mixer, the temperature was raised to 120 ° C, dispersed at 800 rpm for 18 minutes, then added 0. 008 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a kind for 3D.
  • Printing is performed through the nozzle of the 3D printer, and the polymer coated on the surface of the aluminum powder is melted and infiltrated with aluminum powder particles under the condition of 13 CTC, and the aluminum powder particles are bonded to form a metal crucible after cooling and solidification, and the polymerization is performed by post-sintering.
  • the material is decomposed, and the aluminum powder is gradually melted and solidified to form an aluminum metal piece. Since the aluminum powder has a small particle size and a uniform distribution, the melting temperature is low and the melting is uniform, and the internal structure of the metal aluminum member is uniform during the 3D printing manufacturing, and the molding precision of the product is improved.
  • [0049] 2) After cooling the molten aluminum-silica composite obtained in the step 1), grinding is performed under the protection of argon gas, and the pore diameter of 100-150 nm of silica is used as the separator for granulating the aluminum powder, which is not only easy. Grinding and pulverizing dispersion, and the obtained aluminum powder has a uniform particle size distribution and a low oxygen content;
  • step 3 100 parts by weight of the aluminum powder obtained in step 2), 1.0 part by weight of acrylate was added to the reaction mixer, the temperature was raised to 850 ° C, dispersed at 900 rpm for 20 minutes, then added 0. 01 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a 3D printing.
  • Aluminum powder 100 parts by weight of the aluminum powder obtained in step 2), 1.0 part by weight of acrylate was added to the reaction mixer, the temperature was raised to 850 ° C, dispersed at 900 rpm for 20 minutes, then added 0. 01 parts by weight of the initiator 2, 3-diphenylbutyronitrile. Under the action of the initiator, the monomer is polymerized on the surface of the aluminum powder to form a coating film, and the aluminum powder is polymerized to obtain a 3D printing.
  • Aluminum powder 100 parts
  • Printing is performed through the nozzle of the 3D printer, and the polymer coated on the surface of the aluminum powder is melted and infiltrated with aluminum powder particles at 125 ° C. After cooling and solidification, the aluminum powder particles are bonded to form a metal crucible, and after sintering, The polymer is decomposed and the aluminum powder is gradually melted and solidified to form an aluminum metal member. Since the aluminum powder has a small particle size and a uniform distribution, the melting temperature is low and the melting is uniform, and the internal structure of the metal aluminum member is uniform during the 3D printing manufacturing, and the molding precision of the product is improved.
  • the aluminum powder for 3D printing of the present invention is used as a separator for granulating aluminum powder through a pore size of 100-150 nm of white carbon black, so that the aluminum powder is easily ground and pulverized, and the obtained aluminum powder is nanometer-sized, and the particle size is The distribution is uniform, and the sphericity is 0.75 or more.
  • a liquid monomer is dispersed, and the surface of the aluminum powder is coated and polymerized.
  • the obtained aluminum powder has low melting temperature and uniform melting, is used for uniform internal structure of metal in 3D printing manufacturing, and has improved product forming precision, and can be used for preparing precision metal products of complicated components; the surface of aluminum powder is coated with a thin layer of adhesive by polymerization. Effectively prevent oxidation, so that aluminum powder is used in 3D printing to produce a polymer with high fluidity and good thermal bond formability, oxygen content less than 323 ppm, and surface coating of aluminum powder at 135 ° C or lower. Melt and wet the aluminum powder particles for low temperature printing.

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Abstract

一种用于3D打印的铝粉,该铝粉是以白炭黑为载体,在真空条件下,将铝在680℃熔融后,停留在白炭黑的空隙中,通过氩气保护研磨形成平均粒径在50-100nm、球形度为0.75以上球形铝粉,通过单体在铝粉表面包覆聚合,使球形铝粉含氧率降低,防止氧化铝对铝的融化造成影响,得到的铝粉熔化温度低,熔化均匀,用于3D打印制造时金属内部组织均匀,产品成型精度提高,可以用于制备复杂构件的精密金属制品。

Description

发明名称: 一种用于 3D打印的铝粉及其制备方法 技术领域
[0001] 本发明属于 3D打印制造领域, 具体涉及一种用于 3D打印制造的铝粉, 并进一步 涉及该铝粉的制备方法。
背景技术
[0002] 3D打印技术是一种通过逐层增加堆积材料来生成三维实体的快速增材制造技术 , 不但克服了传统减材制造造成的损耗, 而且使产品制造更智能化, 更精准, 更高效。 尤其是涉及到复杂形状的高端制造, 3D打印技术显示出巨大的优越性 。 3D打印技术是一项具有工业革命意义的高新制造技术, 代表了世界制造业发 展的新趋势, 对于加快先进制造业发展、 促进工业转型升级具有重要的引领作 用。 随着高端制造业的发展, 目前 3D打印制造技术受到高度关注, 与机器人技 术、 人工智能技术一起被称为推动第三次工业革命的关键技术。
[0003] 由于 3D打印制造技术完全改变了产品的成型方式和原理, 是对传统制造模式的 颠覆, 因此材料瓶颈成为限制 3D打印发展的问题, 也是 3D 打印突破创新的关键 点和难点所在。 目前, 3D打印技术中常用的材料是塑料材料, 利用塑料材料热 塑性可熔融的特性, 在熔融状态下, 从喷头处挤压出来, 通过凝固层层叠加最 终形成产品。 由于塑料材料良好的热流动性、 快速冷却粘接性、 较高的机械强 度, 在 3D打印制造领域得到快速的应用和发展。 而 3D打印的最终发展是在高端 工业领域应用, 树脂塑料还无法满足高端工业 3D打印的需要, 因此 3D打印材料 逐步从树脂塑料向金属材料发展。
[0004] 金属粉末作为 3D打印原料, 主要采用高功率的能量束如激光、 电子束作为热源 , 使粉末材料进行选区熔化, 冷却结晶后形成堆积层连续成型, 形成最终产品 。 由于金属粉末熔化温度高, 容易氧化, 影响制品的强度, 且激光熔化后的材 料凝固会造成金属体积收缩, 造成巨大的材料热应力, 严重影响材料强度。 另 夕卜, 由于金属粉末粒径和分布的影响, 冷却结晶过程复杂, 结晶过程很难定量 控制, 一旦出现晶体粗大、 枝晶等必将造成材料成型后的力学性能降低的问题 , 最终结果就是关键构件没办法获得实际应用。
中国发明专利 CN103862040A公开了一种用于 3D打印的镁基金属粉末材料, 以包 裹有松香包膜的镁粉为基本材料, 以包裹有松香薄膜的镍粉为支撑材料, 以铝 粉为中间材料, 通过混合搅拌而成。 为了得到高强度的合金器件, 采用了多种 金属共混的方法。
[0005] 中国发明专利 CN103801704A公开了一种用于 3D打印的铜粉, 采用氩气保护炉熔 炼 TU0无氧铜至 1250〜1400°C, 通过炉底吹氩来去除熔融铜液内的夹杂, 使铜液 完全熔化并温度均匀。 通过漏包坩埚和导流嘴流经气雾化喷嘴, 形成小液滴, 得到的铜粉球形较好, 但粒径较大, 因此在用于 3D打印制造时熔融温度高, 难 以控制。
[0006] 根据上述, 目前在 3D打印制造应用的金属粉末, 存在着熔融温度高、 粒径大、 氧含量高、 球形度差、 成分均匀性差以及粒度分布不佳等问题。 因此金属粉由 于粗细不均匀, 熔化不均, 在凝固时会造成体积收缩, 造成材料结构缺陷, 强 度受损
发明概述
技术问题
[0007] 目前 3D打印金属粉末有粒径粗、 分布不均匀、 含氧量高、 熔化温度高的缺陷。
问题的解决方案
技术解决方案
[0008] 本发明提出一种用于 3D打印的铝粉。 该铝粉是以白炭黑为载体, 在真空条件下 , 将铝在 68CTC熔融后, 停留在白炭黑的空隙中, 通过氩气保护研磨形成球形铝 粉, 使球形铝粉含氧率降低, 防止氧化铝对铝的融化造成影响, 通过单体在铝 粉表面包覆聚合, 从而使铝粉用于 3D打印制造。 进一步提供用于 3D打印铝粉的 制备方法。
[0009] 一种用于 3D打印的铝粉, 是通过如下技术方案实现的:
[0010] 一种用于 3D打印的铝粉, 其特征是: 以白炭黑为载体, 白炭黑与铝的质量配比 为 1 : 300-500, 金属铝熔融停留在白炭黑的的空隙中, 通过研磨细化得到平均粒 径在 50-100nm、 球形度为 0. 75以上球形铝粉, 球形铝粉表面包覆单体并聚合, 可用于 3D打印制造。
[0011] 所述白炭黑的孔径为 100_150nm。
[0012] 所述的单体为丙烯酸酯、 甲基丙烯酸酯、 苯乙烯中的至少一种。
[0013] 本发明一种用于 3D打印的铝粉的制备方法, 其特征是按照如下方式进行:
[0014] 1 ) 将纯度为 99. 5%以上的金属铝置于真空炉中, 在 680°C熔融后, 按照白炭黑 与铝的质量配比为 1 : 300-500将白炭黑加入真空炉, 维持真空, 以 50-lOOrpm的 转速将白炭黑与熔融铝分散 3-5min, 使熔融铝停留在白炭黑的多孔的空隙中;
[0015] 2 ) 将步骤 1)得到的熔融铝-白炭黑复合物冷却后, 在氩气保护下进行研磨, 以 白炭黑 100-150nm的孔径作为铝粉成粒的隔离膜, 不但易于研磨粉碎分散, 而且 得到的铝粉粒径分布均匀, 氧含量低;
[0016] 3 ) 将步骤 2 ) 得到的铝粉 100重量份、 0. 5-1. 0重量份的单体加入反应混合器, 温度升至 80-120°C, 以 400-900rpm的高速搅拌分散 15-20分钟, 然后加入 0. 008- 0. 01重量份的引发剂, 所述的单体为丙烯酸酯、 甲基丙烯酸酯、 苯乙烯中的至 少一种, 所述的引发剂选用 2, 3-二苯基丁腈, 在引发剂的作用下, 单体在铝粉 表面聚合形成一层包膜, 聚合包覆铝粉, 得到一种用于 3D打印的铝粉。
[0017] 本发明一种用于 3D打印的铝粉, 通过白炭黑 100-150nm的孔径作为铝粉成粒的 隔离膜, 使得铝粉易于研磨粉碎, 得到的铝粉为纳米级, 粒径分布均匀, 球形 度为 0. 75以上, 为了使纳米级铝粉充分分散和具有粘接性, 采用了液状单体分 散、 包覆铝粉表面并聚合。 得到的铝粉熔化温度低, 熔化均匀, 用于 3D打印制 造时金属内部组织均匀, 产品成型精度提高, 可以用于制备复杂构件的精密金 属制品; 铝粉表面通过聚合包覆薄层粘接剂, 有效防止被氧化, 从而使铝粉用 于 3D打印制造具有高流动性和良好的热粘接成型性, 含氧量低于 323ppm, 在 135 °C以下条件下铝粉表面包覆的聚合物熔化并浸润铝粉颗粒, 实现低温打印。 发明的有益效果
有益效果
[0018] 本发明一种用于 3D打印的铝粉及其制备方法, 与现有技术相比, 其突出的特点 和优异的效果在于:
[0019] 1、 本发明一种用于 3D打印的铝粉, 以白炭黑为载体, 平均粒径在 50-100nm、 球形度为 0. 75以上, 球形铝粉表面包覆单体并聚合, 可用于 3D打印制造。
[0020] 2、 本发明一种用于 3D打印的铝粉, 粒径达到纳米级, 粒径分布均匀, 因此熔 化温度低, 熔化均匀, 用于 3D打印制造时金属内部组织均匀, 产品成型精度提 高, 可以用于制备复杂构件的精密金属制品。
[0021] 3、 本发明一种用于 3D打印的铝粉, 铝粉表面通过聚合包覆薄层粘接剂, 有效 防止被氧化, 从而使铝粉用于 3D打印制造具有高流动性和良好的热粘接成型性
, 力学性能优异。
[0022] 4、 本发明一种用于 3D打印的铝粉的制备方法, 通过白炭黑 100-150nm的孔径作 为铝粉成粒的隔离膜, 使得铝粉易于研磨粉碎, 得到的铝粉粒径分布均匀, 球 度高, 通过单体在铝粉表面包覆聚合, 包覆完全, 包覆层薄, 大幅减少了粘接 剂对金属制品强度的影响。
实施该发明的最佳实施例
本发明的最佳实施方式
[0023] 实施例 1
[0024] 1 ) 将纯度为 99. 5%以上的金属铝置于真空炉中, 在 680°C熔融后, 按照白炭黑 与铝的质量配比为 1 : 300将白炭黑加入真空炉, 维持真空, 以 50rpm的转速将白 炭黑与熔融铝分散 5min, 使熔融铝停留在白炭黑的多孔的空隙中;
[0025] 2 ) 将步骤 1)得到的熔融铝-白炭黑复合物冷却后, 在氩气保护下进行研磨, 以 白炭黑 100-150nm的孔径作为铝粉成粒的隔离膜, 不但易于研磨粉碎分散, 而且 得到的铝粉粒径分布均匀, 氧含量低;
[0026] 3 ) 将步骤 2 ) 得到的铝粉 100重量份、 0. 5重量份的丙烯酸酯加入反应混合器, 温度升至 80°C, 以 400rpm的高速搅拌分散 15分钟, 然后加入 0. 008重量份的引发 剂 2, 3-二苯基丁腈, 在引发剂的作用下, 丙烯酸酯在铝粉表面聚合形成一层包 膜, 聚合包覆铝粉, 得到一种用于 3D打印的铝粉。
[0027] 将实施例 1得到的铝粉通过检测: 性能数据如下表:
[] [表 1]
Figure imgf000006_0001
[0028] 通过 3D打印机的喷嘴进行打印, 在 125°C条件下铝粉表面包覆的聚合物熔化并 浸润铝粉颗粒, 冷却凝固后将铝粉颗粒粘接形成金属枉件, 通过后期烧结, 将 聚合物分解, 铝粉逐步熔化固化形成铝质金属件。 由于铝粉粒径细小、 分布均 匀, 因此熔化温度低, 熔化均匀, 用于 3D打印制造时金属铝件内部组织均匀, 产品成型精度提高。
发明实施例
本发明的实施方式
[0029] 实施例 2
[0030] 1 ) 将纯度为 99. 5%以上的金属铝置于真空炉中, 在 680°C熔融后, 按照白炭黑 与铝的质量配比为 1 : 400将白炭黑加入真空炉, 维持真空, 以 lOOrpm的转速将白 炭黑与熔融铝分散 5min, 使熔融铝停留在白炭黑的多孔的空隙中;
[0031] 2 ) 将步骤 1)得到的熔融铝-白炭黑复合物冷却后, 在氩气保护下进行研磨, 以 白炭黑 100-150nm的孔径作为铝粉成粒的隔离膜, 不但易于研磨粉碎分散, 而且 得到的铝粉粒径分布均匀, 氧含量低;
[0032] 3 ) 将步骤 2 ) 得到的铝粉 100重量份、 0. 5重量份的甲基丙烯酸酯加入反应混合 器, 温度升至 80°C, 以 900rpm的高速搅拌分散 20分钟, 然后加入 0. 01重量份的 引发剂 2, 3-二苯基丁腈, 在引发剂的作用下, 单体在铝粉表面聚合形成一层包 膜, 聚合包覆铝粉, 得到一种用于 3D打印的铝粉。 [0033] 将实施例 2得到的铝粉通过检测: 性能数据如下表:
[] [表 2]
Figure imgf000007_0001
[0034] 通过 3D打印机的喷嘴进行打印, 在 135°C条件下铝粉表面包覆的聚合物熔化并 浸润铝粉颗粒, 冷却凝固后将铝粉颗粒粘接形成金属枉件, 通过后期烧结, 将 聚合物分解, 铝粉逐步熔化固化形成铝质金属件。 由于铝粉粒径细小、 分布均 匀, 因此熔化温度低, 熔化均匀, 用于 3D打印制造时金属铝件内部组织均匀, 产品成型精度提高。
[0035] 实施例 3
[0036] 1 ) 将纯度为 99. 5%以上的金属铝置于真空炉中, 在 680°C熔融后, 按照白炭黑 与铝的质量配比为 1 : 500将白炭黑加入真空炉, 维持真空, 以 80rpm的转速将白 炭黑与熔融铝分散 3-5min, 使熔融铝停留在白炭黑的多孔的空隙中;
[0037] 2 ) 将步骤 1)得到的熔融铝-白炭黑复合物冷却后, 在氩气保护下进行研磨, 以 白炭黑 100-150nm的孔径作为铝粉成粒的隔离膜, 不但易于研磨粉碎分散, 而且 得到的铝粉粒径分布均匀, 氧含量低;
[0038] 3 ) 将步骤 2 ) 得到的铝粉 100重量份、 0. 5重量份的苯乙烯加入反应混合器, 温 度升至 100°C, 以 400rpm的高速搅拌分散 15分钟, 然后加入 0. 01重量份的引发剂 2, 3-二苯基丁腈, 在引发剂的作用下, 单体在铝粉表面聚合形成一层包膜, 聚 合包覆铝粉, 得到一种用于 3D打印的铝粉。
[0039] 将实施例 1得到的铝粉通过检测: 性能数据如下表: [] [表 3]
Figure imgf000008_0001
[0040] 通过 3D打印机的喷嘴进行打印, 在 115°C条件下铝粉表面包覆的聚合物熔化并 浸润铝粉颗粒, 冷却凝固后将铝粉颗粒粘接形成金属枉件, 通过后期烧结, 将 聚合物分解, 铝粉逐步熔化固化形成铝质金属件。 由于铝粉粒径细小、 分布均 匀, 因此熔化温度低, 熔化均匀, 用于 3D打印制造时金属铝件内部组织均匀, 产品成型精度提高。
[0041] 实施例 4
[0042] 1 ) 将纯度为 99. 5%以上的金属铝置于真空炉中, 在 680°C熔融后, 按照白炭黑 与铝的质量配比为 1 : 450将白炭黑加入真空炉, 维持真空, 以 50rpm的转速将白 炭黑与熔融铝分散 3min, 使熔融铝停留在白炭黑的多孔的空隙中;
[0043] 2 ) 将步骤 1)得到的熔融铝-白炭黑复合物冷却后, 在氩气保护下进行研磨, 以 白炭黑 100-150nm的孔径作为铝粉成粒的隔离膜, 不但易于研磨粉碎分散, 而且 得到的铝粉粒径分布均匀, 氧含量低;
[0044] 3 ) 将步骤 2 ) 得到的铝粉 100重量份、 0. 8重量份的甲基丙烯酸酯加入反应混合 器, 温度升至 120°C, 以 800rpm的高速搅拌分散 18分钟, 然后加入 0. 008重量份 的引发剂 2, 3-二苯基丁腈, 在引发剂的作用下, 单体在铝粉表面聚合形成一层 包膜, 聚合包覆铝粉, 得到一种用于 3D打印的铝粉。
[0045] 将实施例 1得到的铝粉通过检测: 性能数据如下表:
[] [表 4]
Figure imgf000009_0001
[0046] 通过 3D打印机的喷嘴进行打印, 在 13CTC条件下铝粉表面包覆的聚合物熔化并 浸润铝粉颗粒, 冷却凝固后将铝粉颗粒粘接形成金属枉件, 通过后期烧结, 将 聚合物分解, 铝粉逐步熔化固化形成铝质金属件。 由于铝粉粒径细小、 分布均 匀, 因此熔化温度低, 熔化均匀, 用于 3D打印制造时金属铝件内部组织均匀, 产品成型精度提高。
[0047] 实施例 5
[0048] 1 ) 将纯度为 99. 5%以上的金属铝置于真空炉中, 在 680°C熔融后, 按照白炭黑 与铝的质量配比为 1 : 500将白炭黑加入真空炉, 维持真空, 以 90rpm的转速将白 炭黑与熔融铝分散 3min, 使熔融铝停留在白炭黑的多孔的空隙中;
[0049] 2 ) 将步骤 1)得到的熔融铝-白炭黑复合物冷却后, 在氩气保护下进行研磨, 以 白炭黑 100-150nm的孔径作为铝粉成粒的隔离膜, 不但易于研磨粉碎分散, 而且 得到的铝粉粒径分布均匀, 氧含量低;
[0050] 3 ) 将步骤 2 ) 得到的铝粉 100重量份、 1. 0重量份的丙烯酸酯加入反应混合器, 温度升至 850°C, 以 900rpm的高速搅拌分散 20分钟, 然后加入 0. 01重量份的引发 剂 2, 3-二苯基丁腈, 在引发剂的作用下, 单体在铝粉表面聚合形成一层包膜, 聚合包覆铝粉, 得到一种用于 3D打印的铝粉。
[0051] 将实施例 1得到的铝粉通过检测: 性能数据如下表:
[] [表 5]
Figure imgf000010_0001
[0052] 通过 3D打印机的喷嘴进行打印, 在 125°C条件下铝粉表面包覆的聚合物熔化并 浸润铝粉颗粒, 冷却凝固后将铝粉颗粒粘接形成金属枉件, 通过后期烧结, 将 聚合物分解, 铝粉逐步熔化固化形成铝质金属件。 由于铝粉粒径细小、 分布均 匀, 因此熔化温度低, 熔化均匀, 用于 3D打印制造时金属铝件内部组织均匀, 产品成型精度提高。
工业实用性
[0053] 本发明一种用于 3D打印的铝粉, 通过白炭黑 100-150nm的孔径作为铝粉成粒的 隔离膜, 使得铝粉易于研磨粉碎, 得到的铝粉为纳米级, 粒径分布均匀, 球形 度为 0. 75以上, 为了使纳米级铝粉充分分散和具有粘接性, 采用了液状单体分 散、 包覆铝粉表面并聚合。 得到的铝粉熔化温度低, 熔化均匀, 用于 3D打印制 造时金属内部组织均匀, 产品成型精度提高, 可以用于制备复杂构件的精密金 属制品; 铝粉表面通过聚合包覆薄层粘接剂, 有效防止被氧化, 从而使铝粉用 于 3D打印制造具有高流动性和良好的热粘接成型性, 含氧量低于 323ppm, 在 135 °C以下条件下铝粉表面包覆的聚合物熔化并浸润铝粉颗粒, 实现低温打印。

Claims

权利要求书
[权利要求 1] 一种用于 3D打印的铝粉, 其特征是: 以白炭黑为载体, 白炭黑与铝的 质量配比为 1 : 300-500, 金属铝熔融停留在白炭黑的空隙中, 通过研 磨细化得到平均粒径在 50-100nm、 球形度为 0. 75以上球形铝粉, 球形 铝粉表面包覆单体并聚合, 可用于 3D打印制造; 所述白炭黑的孔径为 100-150nm; 所述的单体为丙烯酸酯、 甲基丙烯酸酯、 苯乙烯中的至 少一种。
[权利要求 2] 权利要求 1所述一种用于 3D打印的铝粉的制备方法, 其特征是按照如 下方式进行:
1 ) 将纯度为 99. 5%以上的金属铝置于真空炉中, 在 680°C熔融后, 按 照白炭黑与铝的质量配比为 1 : 300-500将白炭黑加入真空炉, 维持真 空, 以 50-lOOrpm的转速将白炭黑与熔融铝分散 3-5min, 使熔融铝停 留在白炭黑的多孔空隙中;
2 ) 将步骤 1)得到的熔融铝-白炭黑复合物冷却后, 在氩气保护下进行 研磨, 以白炭黑 100-150nm的孔径作为铝粉成粒的隔离膜, 不但易于 研磨粉碎分散, 而且得到的铝粉粒径分布均匀, 氧含量低;
3 ) 将步骤 2 ) 得到的铝粉 100重量份、 0. 5-1. 0重量份的单体加入反应 混合器, 温度升至 80-120°C, 以 400-900rpm的高速搅拌分散 15-20分 钟, 然后加入 0. 008-0. 01重量份的引发剂, 所述的单体为丙烯酸酯、 甲基丙烯酸酯、 苯乙烯中的至少一种, 所述的引发剂选用 2, 3-二苯 基丁腈, 在引发剂的作用下, 单体在铝粉表面聚合形成一层包膜, 聚 合包覆铝粉, 得到一种用于 3D打印的铝粉。
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