KR20040077294A - Process for preparing ultrafine α- alumina powder - Google Patents

Process for preparing ultrafine α- alumina powder Download PDF

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KR20040077294A
KR20040077294A KR1020030012800A KR20030012800A KR20040077294A KR 20040077294 A KR20040077294 A KR 20040077294A KR 1020030012800 A KR1020030012800 A KR 1020030012800A KR 20030012800 A KR20030012800 A KR 20030012800A KR 20040077294 A KR20040077294 A KR 20040077294A
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alumina
powder
aluminum
nano
solution
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KR100491711B1 (en
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황규홍
이종국
조명제
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대한민국 (경상대학교 총장)
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C01F7/02—Aluminium oxide; Aluminium hydroxide; Aluminates
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer

Abstract

PURPOSE: Provided is a preparation method of nano-sized α-alumina powder by adding polymeric materials to aluminum solution, aluminum hydroxide or gamma-alumina suspension for preventing alumina particles from growing in calcination for α-alumina. CONSTITUTION: The nano-sized α-alumina(α-Al2O3) powder is prepared by the following steps of: (i) adding polymer materials or polymerized organics to solution of Al(NO3)3, AlCl3 or Al2(SO4)3, primary particles of Al(OH)3 obtained from precipitation of the solution or suspension of gamma(γ)-Al2O3 obtained from calcination of primary particles, wherein coupling agents such as triethanolamin and citric acid are added to Al(NO3)3 solution in a molar ratio of 1:2-1:5 and then low molecular organics such as ethylene glycol and glycine are added to the mixed solution of Al(NO3)3 and coupling agent to polymerize organic materials; (ii) milling solidified resin carbides containing aluminum ions; (iii) calcining carbide powder between 1000-1200deg.C in reductive atmosphere for transition of α-alumina from amorphous alumina; and thermal treating calcined powder at 600deg.C in the air for removal of remaining carbides in alumina powder.

Description

초미립 α-알루미나 분말의 제조방법{Process for preparing ultrafine α- alumina powder }Process for preparing ultrafine α-alumina powder

본 발명은 α-알루미나(Al2O3) 분말을 나노 크기의 초미립자로 제조하는 방법에 관한 것이다. 더욱 상세하게는 종래 사용되는 서브 마이크론 크기의 알루미나(Al2O3) 분말보다 더욱 미세한 나노 크기의 초미립 분말을 경제성 있게 제조하기 위한 방법에 관한 것이다.The present invention relates to a method for preparing α-alumina (Al 2 O 3 ) powder into nano-sized ultra-fine particles. More particularly, the present invention relates to a method for economically preparing nano-sized ultrafine powders more finely than conventionally used submicron-sized alumina (Al 2 O 3 ) powders.

이러한 서브 마이크론 크기의 알루미나(Al2O3) 분말은 베이어법과 같은 침전법(Precipitation)에 의해 제조되어졌는데 비정질 상에서 α-Al2O3로의 높은 상전이 온도 때문에 입자 성장을 제어하기가 힘들었다. 따라서 지금까지의 초미립 분말은 졸-겔(Sol-Gel) 법이나 기상 열분해법 같은 고비용의 제조공정에 의해 제조되어져 왔다.These submicron-sized alumina (Al 2 O 3 ) powders were prepared by precipitation such as Bayer's method, and it was difficult to control grain growth due to the high phase transition temperature to α-Al 2 O 3 in the amorphous phase. Thus, ultrafine powders have been produced by expensive manufacturing processes such as sol-gel or gas phase pyrolysis.

여기서는 경제적인 침전법을 사용하되, α-Al2O3로의 상전이 시, 입자 성장을 제어함으로써 초미립의 나노 분말을 합성하고, 소결온도를 낮춤으로써 입성장을억제하여 소결체의 강도와 인성을 획기적으로 증진시킬 수 있는 방안을 제시하고자 하였다.Here, an economical precipitation method is used, but in the phase transition to α-Al 2 O 3 , ultrafine nanopowders are synthesized by controlling particle growth, and the grain growth is suppressed by lowering the sintering temperature, thereby dramatically reducing the strength and toughness of the sintered body. The purpose of this study was to suggest a way to promote this.

침전법으로 제조된 수산화알루미늄[Al(OH)3]의 초기 입자 크기는 10 내지 50nm 정도의 크기를 가지지만 가열에 의한 탈수 후 γ, δ, θ-상을 거쳐 최종적으로 안정한 α-Al2O3상으로 전이되는 온도가 높고 이 과정에서 입자간 합체가 일어나 서브 마이크론 대의 큰 입자로 성장하게 된다.The initial particle size of aluminum hydroxide [Al (OH) 3 ] prepared by the precipitation method has a size of about 10 to 50 nm, but finally stable α-Al 2 O through γ, δ, θ-phase after dehydration by heating. The transition temperature to the three phases is high and in this process intergranular coalescence occurs to grow into large particles in the submicron range.

따라서, 본 발명은 침전법 등 비교적 경제적으로 제조된 수산화알루미늄[Al(OH)3]으로부터 열처리에 의해 α상의 알루미나(Al2O3) 분말을 제조할 때 높은 상전이 온도(1025℃ 이상)에서의 1차 입자의 합체에 의한 2차 입자로의 입성장을 억제하기 위해 1차 입자 사이에 유기물 등을 개재시켜 입자간 합체 없이 상전이를 유도함으로써 침전시의 입자크기를 유지시키는 방법으로 α-Al2O3분말을 나노 크기의 초미립자로 제조하는 방법을 제공하는데 그 목적이 있는 것이다.Accordingly, the present invention provides a phase alumina (Al 2 O 3 ) powder at high phase transition temperature (1025 ° C. or higher) by heat treatment from aluminum hydroxide [Al (OH) 3 ], which is relatively economically produced, such as precipitation. Α-Al 2 is a method of maintaining the particle size at the time of precipitation by inducing a phase transition without coalescence between particles by interposing organic materials or the like between primary particles in order to suppress particle growth into secondary particles by coalescence of primary particles. It is an object of the present invention to provide a method for preparing O 3 powder into nano-sized ultrafine particles.

본 발명에 의하면, 먼저 질화알루미늄[Al(NO3)3], 염화알루미늄[AlCl3] 또는 황산알루미늄[Al2(SO4)3] 등의 수용액, 또는 이 수용액의 침전에 의해 얻어진 수산화알루미늄[Al(OH)3]의 1차 입자나 이를 저온에서 하소하여 아직 입성장이 일어나지 않은 γ-Al2O3등의 현탁액에 고분자 물질을 직접 첨가하거나 단분자 유기물을 고분자화시켜 이들을 Al 이온이나 1차 입자 사이에 개재되도록 하는 것이다.According to the present invention, an aqueous solution of aluminum nitride [Al (NO 3 ) 3 ], aluminum chloride [AlCl 3 ] or aluminum sulfate [Al 2 (SO 4 ) 3 ], or aluminum hydroxide obtained by precipitation of this aqueous solution [ Al (OH) 3 ] primary particles or calcination at low temperature, γ-Al 2 O 3 and other suspensions that do not yet have grain growth, the polymer material is added directly or the monomolecular organics are polymerized to give them Al ions or primary To intervene between particles.

염화알루미늄[AlCl3]이나 황산알루미늄[Al2(SO4)3] 의 경우 잔류 음이온에 의한 최종 입자간 응집이 심하게 일어나므로 질화알루미늄[Al(NO3)3] 수용액에 Al 이온을 포획할 커플링제(coupling agent) 로써 트리에탄올아민(Triethanolamin) 이나 구연산(Citric acid)을 첨가한 다음 에틸렌글리콜(Ethylene glycol) 이나 글리신(Glycine), 자당(Sucrose) 등의 저분자 유기물을 고분자화시켜서 상기 커플링제와 함께 개재시킬 수 있다.Aluminum chloride [AlCl 3] and aluminum sulfate [Al 2 (SO 4) 3 ] , agglomeration between the final particles by residual anions severely up, because the aluminum nitride [Al (NO 3) 3] coupling to trap the Al ions in aqueous solution for Triethanolamine or citric acid is added as a coupling agent, and low molecular weight organic materials such as ethylene glycol, glycine, and sucrose are polymerized together with the coupling agent. Can be intervened.

본 발명에 따르면, 상기 알루미나 공급원과 커플링제는 몰비로 1 : 2 내지 1 : 5의 범위로 첨가하여 사용하는 것이 바람직하고, 이들을 80 내지 110℃의 온도 범위로 가열한 후에 상기 저분자 유기물에 첨가하는 것이 좋다. 여기서, 고분자화를 위한 저분자 유기물의 사용량은 커플링제와외 몰비로 1 : 2 내지 1 : 5의 범위로 설정하여 사용하는 것이 바람직하다.According to the present invention, the alumina source and the coupling agent are preferably used in a molar ratio in the range of 1: 2 to 1: 5, and these are added to the low molecular organic substance after heating to a temperature range of 80 to 110 ° C. It is good. Here, it is preferable to use the low molecular weight organic substance for polymerization in the range of 1: 2 to 1: 5 by molar ratio other than a coupling agent.

다음에 이를 1025℃ 이상의 고온으로 공기 중에서 열처리하게 되면 유기물이 열분해 된 다음 α-Al2O3로 상전이되면서 합체가 일어나게 된다.Next, when this is heat-treated in air at a high temperature of 1025 ℃ or more, the organic material is thermally decomposed and then coalesced as the phase transition to α-Al 2 O 3 .

따라서, 본 발명에 따른 1차 하소에 의하면, 개재된 유기물의 산화가 일어나지 않도록, 즉 탄화물이 산화되지 않도록 환원분위기 하에서 1000℃와 1200℃ 사이의 온도 범위에서 1 내지 3시간 동안 열처리를 하여 α-Al2O3로의 상전이시 1차 입자간에 합체가 일어나지 않게 됨으로 나노 크기를 유지시키면서 α-Al2O3로의 상전이를 일으킬 수 있다.Therefore, according to the primary calcination according to the present invention, the heat treatment is performed for 1 to 3 hours in a temperature range between 1000 ° C. and 1200 ° C. under a reducing atmosphere so that oxidation of the intervening organic matter does not occur, that is, carbides are not oxidized. When the phase transition to Al 2 O 3 is not coalesced between the primary particles it can cause a phase transition to α-Al 2 O 3 while maintaining the nano-size.

또한, 이 분말은 다량의 유기물을 포함하게 되므로 탄화물 제거를 위해 2차로 600℃와 900℃ 사이의 온도 범위에서 1 내지 3 시간 동안 공기 중에서 2차 하소를 행함으로써 더 이상의 입성장이나 합체 없이 탄화물을 산화에 의해 완전히 제거된 30nm 내지 50nm 정도의 크기를 갖는 나노 크기의 초미립 α-Al2O3분말을 제조할 수 있다.In addition, since the powder contains a large amount of organic matter, secondary calcination in air for 1 to 3 hours in the temperature range between 600 ° C. and 900 ° C. for the removal of carbides is performed to remove carbides without further grain growth or coalescence. Nano-size ultrafine α-Al 2 O 3 powder having a size of about 30 nm to 50 nm completely removed by oxidation may be prepared.

다른 한편으로, 상기한 바와 같이 질화알루미늄[Al(NO3)3] 수용액을 사용할 경우 유기물의 휘발 외에도 NO3의 분해가 필요하여 2단 하소까지의 감량이 90％를 넘게 된다. 따라서, 하소시 감량의 범위를 40％와 80％의 사이로 줄이기 위하여 질화알루미늄[Al(NO3)3] 수용액을 암모니아로 침전시킨 수산화알루미늄[Al(OH)3]의 1차 입자나 이를 저온, 예를 들면 600℃ 이하의 저온에서 하소한 γ-Al2O3등의 현탁액을 사용할 수 있다.On the other hand, in the case of using the aluminum nitride [Al (NO 3 ) 3 ] aqueous solution as described above, in addition to volatilization of organic matter, decomposition of NO 3 is required, and the loss up to two-stage calcination exceeds 90%. Therefore, primary particles of aluminum hydroxide [Al (OH) 3 ] in which an aqueous solution of aluminum nitride [Al (NO 3 ) 3 ] was precipitated with ammonia in order to reduce the range of weight loss during calcination between 40% and 80%, or a low temperature, For example, suspension such as γ-Al 2 O 3 calcined at a low temperature of 600 ° C. or lower can be used.

이 경우에는 상기와 같이 단분자를 커플링제와 고분자화시켜 입자 표면에 유기물을 개재하여 Al 이온을 함유하는 수지 탄화물을 제조할 수도 있지만, 올레산(Oleic acid), 폴리에틸렌글리콜(PEG) 또는 폴리비닐알콜(PVA)과 같은 고분자량의 분산제에 의해 표면 코팅이 가능하므로 이들을 직접 상기 1차 입자에 부착시켜 유기물을 개재시킴으로써 1차 입자를 둘러싸는 수지 탄화물을 제조할 수 있다.In this case, as described above, a single molecule may be polymerized with a coupling agent to prepare a resin carbide containing Al ions via an organic material on the particle surface, but oleic acid, polyethylene glycol (PEG), or polyvinyl alcohol may be prepared. Since surface coating is possible by a high molecular weight dispersing agent such as (PVA), the resin carbide surrounding the primary particles can be prepared by directly attaching them to the primary particles and interposing the organic particles.

다음에 상기한 바와 같이 2단 하소법에 의해 나노 크기의 1차 입자 크기가 그대로 유지된 α상 알루미나 분말을 제조할 수 있다.Next, the α-phase alumina powder in which the nano-sized primary particle size is maintained as it is can be produced by the two-stage calcination method as described above.

이와 같은 본 발명을 실시예를 들어 상세하게 설명하면 다음과 같다.The present invention will be described in detail with reference to Examples.

실시예 1Example 1

먼저 질화알루미늄[Al(NO3)3]과 구연산을 몰 비로 1 : 2 범위로 첨가한 수용액을 80℃로 가열된 에틸렌글리콜 용액에 적하시켜 첨가하였다. 이때 구연산과 에틸렌글리콜의 몰 비를 1 : 2로 하였으며 이를 150℃로 가열하면서 고분자화 반응(polyesterification)과 겔화(gellation)를 유도하였다.First, an aqueous solution containing aluminum nitride [Al (NO 3 ) 3 ] and citric acid in a molar ratio of 1: 2 was added dropwise to an ethylene glycol solution heated to 80 ° C. At this time, the molar ratio of citric acid and ethylene glycol was 1: 2, and this was heated to 150 ° C. to induce polymerization reaction and gelation.

이렇게 얻어진 수지를 350℃ 에서 고화시켜 조분쇄한 다음 3시간 동안 볼 밀링 후 100메쉬의 체를 통과시켜 탄화물 분말을 얻었다. 이 분말을 불활성 분위기 즉 탄화물이 산화되지 않는 분위기 하에서 1000℃에서 1시간 동안 1차 하소를 하여 비정질 상의 알루미나가 α상으로 상전이 되도록 하였다. 상전이가 완료된 탄화물을 포함하는 분말에서 탄화물 제거를 위해 다시 공기 중에서 2차 열처리를 행하였다. 2차 열처리 온도는 600℃의 저온에서 1시간 하소하여 탄화물을 완전히 제거한 결과 30nm 정도의 나노 α상 알루미나를 얻을 수 있었다.The resin thus obtained was solidified at 350 deg. C, coarsely pulverized and then passed through a 100 mesh sieve after ball milling for 3 hours to obtain a carbide powder. The powder was first calcined at 1000 ° C. for 1 hour in an inert atmosphere, that is, in an atmosphere where carbides were not oxidized, so that the alumina in the amorphous phase was phase-changed into the α phase. Secondary heat treatment was further performed in air to remove carbides from the powder containing carbides having completed phase transition. The secondary heat treatment temperature was calcined at a low temperature of 600 ℃ for 1 hour to completely remove the carbide was obtained a nano α-phase alumina of about 30nm.

실시예 2Example 2

질화알루미늄[Al(NO3)3] 수용액에 구연산 대신에 트리에탄올아민을, 에틸렌글리콜 대신에 자당을 사용하여 실시예 1과 같은 유기물 개재 후 2단 하소법을 사용한 결과 상기 실시예 1과 같은 결과를 얻을 수 있었다.Triethanolamine instead of citric acid and sucrose instead of ethylene glycol were used in an aqueous solution of aluminum nitride [Al (NO 3 ) 3 ]. Could get

실시예 3Example 3

상기 실시예 1에서 질화알루미늄[Al(NO3)3] 대신에, 질화알루미늄[Al(NO3)3] 수용액을 암모니아로 침전시킨 수산화알루미늄[Al(OH)3] 의 1차 입자나 이를 600℃ 이하의 저온에서 하소한 α-Al2O3를 사용하고, 고분자량의 분산제로서 올레산을 사용하여 상기 1차 입자 사이에 직접 유기물을 개재시켰다. 이어서 상기 실시예 1과 동일하게 2단 하소하여 40% 정도의 감량 범위에서 50nm 정도의 α상 알루미나 초미분체를 제조하였다.Instead of aluminum nitride [Al (NO 3 ) 3 ] in Example 1, primary particles of aluminum hydroxide [Al (OH) 3 ] precipitated with an aqueous solution of aluminum nitride [Al (NO 3 ) 3 ] with ammonia or 600 using the α-Al 2 O 3 calcined at a low temperature of less than ℃, which was sandwiched between an organic matter directly on the primary particles by using oleic acid as a dispersant of high molecular weight. Subsequently, two steps of calcination were performed in the same manner as in Example 1 to prepare α-phase alumina ultrafine powder of about 50 nm in a weight loss range of about 40%.

본 발명은 질화알루미늄[Al(NO3)3]이나 이의 수화 침전물, 또는 α-Al2O3입자 사이에 에틸렌글리콜과 구연산, 또는 트리에탄올아민과 자당을 고분자화 시키거나 올레산, 폴리에틸렌글리콜(PEG), 폴리비닐알콜( PVA) 등을 흡착 개재시킨 다음 2단 하소에 의해 나노 크기의 입자크기를 유지하는 α-상 알루미나 초미분체를 제조하는 방법으로서, 이렇게 제조된 알루미나는 다른 미분체 알루미나 제조법에 비해 경제성이 우수하고, 저온 소성에 의해 고품위의 제품을 생산할 수 있다.The present invention polymerizes ethylene glycol and citric acid or triethanolamine and sucrose between aluminum nitride [Al (NO 3 ) 3 ] or a hydrated precipitate thereof, or α-Al 2 O 3 particles, or oleic acid, polyethylene glycol (PEG). , Polyvinyl alcohol (PVA) is adsorbed through the two-stage calcination to maintain the α-phase alumina ultra-fine powder to maintain a nano-sized particle size, the alumina thus prepared compared to other fine powder alumina manufacturing method It is excellent in economy and can produce high quality products by low temperature firing.

이렇게 제조된 알루미나는 이소결성 알루미나와 같은 구조용 세라믹스의 원료로 활용이 가능하며, 플라스틱 제품의 강도 증진과 내 마모성 증진을 위해 첨가되는 충진제 등으로의 활용이 가능하다.The alumina thus prepared may be used as a raw material for structural ceramics such as sinterable alumina, and may be used as a filler added to enhance strength and wear resistance of plastic products.

Claims (5)

질화알루미늄[Al(NO3)3], 염화알루미늄[AlCl3] 또는 황산알루미늄[Al2(SO4)3] 등의 수용액으로 이루어진 알루미나 공급원에 입성장 억제를 위한 유기물을 개재시켜 Al 이온을 함유하는 수지 탄화물을 제조한 다음 2단계 하소에 의해 나노 크기의 1차 입자 크기를 그대로 유지하는 것을 특징으로 하는 초미립 α상 알루미나 분말의 제조방법.Alumina source consisting of an aqueous solution such as aluminum nitride [Al (NO 3 ) 3 ], aluminum chloride [AlCl 3 ] or aluminum sulfate [Al 2 (SO 4 ) 3 ] contains an Al ion through an organic material for inhibiting grain growth. The method for preparing ultrafine α-phase alumina powder, characterized in that the resin carbide is prepared and then the primary particle size of nano size is maintained as it is by two-step calcination. 질화알루미늄[Al(NO3)3], 염화알루미늄[AlCl3] 또는 황산알루미늄[Al2(SO4)3] 등의 수용액의 침전에 의해 얻어진 수산화알루미늄[Al(OH)3]의 1차 입자 또는 이를 저온에서 하소하여 아직 입성장이 일어나지 않은 γ-Al2O3등의 현탁액에 고분자 물질을 직접 첨가하거나 단분자 유기물을 고분자화시켜 상기 1차 입자를 둘러싸는 수지 탄화물을 제조한 다음 2단계 하소법에 의해 나노 크기의 1차 입자 크기가 그대로 유지되게 하는 것을 특징으로 하는 초미립 α상 알루미나 미분말의 제조방법.Primary particles of aluminum hydroxide [Al (OH) 3 ] obtained by precipitation of an aqueous solution such as aluminum nitride [Al (NO 3 ) 3 ], aluminum chloride [AlCl 3 ] or aluminum sulfate [Al 2 (SO 4 ) 3 ] Alternatively, calcining it at a low temperature to directly add a polymer material to a suspension such as γ-Al 2 O 3 that has not yet occurred grain growth or polymerize a monomolecular organic material to prepare a resin carbide surrounding the primary particles, followed by two-step calcination A method for producing ultrafine α-phase alumina fine powder, wherein the primary particle size of nano size is maintained as it is by a method. 제 1항 또는 제 2항에 있어서, 상기 유기물은 에틸렌글리콜, 글리신 또는 자당의 저분자 유기물을 Al 이온을 포획하는 트리에탄올아민이나 구연산 등의 커플링제와 고분자화시켜서 개재하는 것을 특징으로 하는 초미립 α상 알루미나 분말의 제조방법.The ultrafine α phase according to claim 1 or 2, wherein the organic material is polymerized with a low molecular weight organic material of ethylene glycol, glycine or sucrose by polymerizing with a coupling agent such as triethanolamine or citric acid which traps Al ions. Method for producing alumina powder. 제 1항 또는 제 2항에 있어서, 상기 고분자는 올레산, 폴리에틸렌글리콜 또는 폴리비닐알콜 중에서 선택하여 되는 것을 특징으로 하는 초미립 α상 알루미나 분말의 제조방법.3. The method of claim 1, wherein the polymer is selected from oleic acid, polyethylene glycol, or polyvinyl alcohol. 4. 제 1항 또는 제 2항에 있어서, 상기 하소는 상기 탄화물이 산화되지 않도록 환원분위기 하에서 1000℃와 1200℃ 사이의 온도 범위에서 1 내지 3시간 동안 열처리를 하여 나노 크기를 유지시키면서 α-Al2O3로의 상전이가 일어나도록 하고, 탄화물 제거를 위해 2차로 600℃와 900℃ 사이의 온도 범위에서 1 내지 3 시간 동안 공기 중에서 하소를 행함을 특징으로 하는 초미립 α상 알루미나 분말의 제조방법.The method according to claim 1 or 2, wherein the calcination is heat-treated for 1 to 3 hours in a temperature range between 1000 ° C and 1200 ° C under a reducing atmosphere so that the carbides are not oxidized, while maintaining the nano-sized α-Al 2 O Method for producing ultrafine α-phase alumina powder, characterized in that the phase transition to 3 to occur, and calcining in air for 1 to 3 hours in the temperature range between 600 ℃ and 900 ℃ second to remove the carbide.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1295152C (en) * 2005-03-25 2007-01-17 天津大学 Electric arc spraying reaction synthesis system and process of preparing nano alumina powder
KR100729378B1 (en) * 2006-06-27 2007-06-15 박경숙 Method for manufacturing calcined alumina using artificial marvel dust and sludge
KR20210080864A (en) * 2019-12-23 2021-07-01 한국세라믹기술원 High heat-dissipating AlN-Elastomer composites and fabrication method thereof
CN113830809A (en) * 2021-10-27 2021-12-24 中国科学院青海盐湖研究所 Preparation method of superfine alumina powder and product thereof
CN115893461A (en) * 2022-12-06 2023-04-04 山东麦丰新材料科技股份有限公司 Production process of nano aluminum oxide polishing powder

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1295152C (en) * 2005-03-25 2007-01-17 天津大学 Electric arc spraying reaction synthesis system and process of preparing nano alumina powder
KR100729378B1 (en) * 2006-06-27 2007-06-15 박경숙 Method for manufacturing calcined alumina using artificial marvel dust and sludge
KR20210080864A (en) * 2019-12-23 2021-07-01 한국세라믹기술원 High heat-dissipating AlN-Elastomer composites and fabrication method thereof
CN113830809A (en) * 2021-10-27 2021-12-24 中国科学院青海盐湖研究所 Preparation method of superfine alumina powder and product thereof
CN115893461A (en) * 2022-12-06 2023-04-04 山东麦丰新材料科技股份有限公司 Production process of nano aluminum oxide polishing powder
CN115893461B (en) * 2022-12-06 2023-11-17 山东麦丰新材料科技股份有限公司 Production process of nano alumina polishing powder

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