WO2013040849A1 - 一种α-氧化铝基磨料及其制备方法 - Google Patents

一种α-氧化铝基磨料及其制备方法 Download PDF

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WO2013040849A1
WO2013040849A1 PCT/CN2012/001037 CN2012001037W WO2013040849A1 WO 2013040849 A1 WO2013040849 A1 WO 2013040849A1 CN 2012001037 W CN2012001037 W CN 2012001037W WO 2013040849 A1 WO2013040849 A1 WO 2013040849A1
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granules
slurry
alumina
nitric acid
gel
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PCT/CN2012/001037
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English (en)
French (fr)
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翟涵
刘海红
林召明
徐纪风
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鲁信创业投资集团股份有限公司
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Priority to JP2013546582A priority Critical patent/JP5647359B2/ja
Publication of WO2013040849A1 publication Critical patent/WO2013040849A1/zh

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    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/10Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on aluminium oxide
    • C04B35/111Fine ceramics
    • C04B35/1115Minute sintered entities, e.g. sintered abrasive grains or shaped particles such as platelets
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K3/00Materials not provided for elsewhere
    • C09K3/14Anti-slip materials; Abrasives
    • C09K3/1409Abrasive particles per se
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3217Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
    • C04B2235/3218Aluminium (oxy)hydroxides, e.g. boehmite, gibbsite, alumina sol
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/327Iron group oxides, their mixed metal oxides, or oxide-forming salts thereof
    • C04B2235/3272Iron oxides or oxide forming salts thereof, e.g. hematite, magnetite
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74Physical characteristics
    • C04B2235/77Density
    • CCHEMISTRY; METALLURGY
    • C04CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04BLIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/70Aspects relating to sintered or melt-casted ceramic products
    • C04B2235/74Physical characteristics
    • C04B2235/78Grain sizes and shapes, product microstructures, e.g. acicular grains, equiaxed grains, platelet-structures
    • C04B2235/785Submicron sized grains, i.e. from 0,1 to 1 micron

Definitions

  • the invention belongs to the field of ⁇ -alumina ceramic abrasive particles and a preparation method thereof, and particularly relates to a low-cost ⁇ -alumina-based abrasive and a preparation method thereof.
  • the general method for preparing ceramic abrasives by melt-gel method is to mix pure boehmite with deionized water, seed crystals and nitric acid to form a uniform fine sol or gel, then dry to remove the moisture in the gel, and then The dried gel large particles are broken into particles slightly larger than the required size, and then calcined at a temperature of 500 ° C to 800 ° C, and then calcined at a temperature of 1300 ° C to 1500 ° C for 5 to 60 minutes to form an oxidation. 5 ⁇ / ⁇ , preferably greater than 3.
  • hardness is generally greater than 20Gpa
  • the hardness of the sintered abrasive particles is generally greater than 3.5 grams / cubic centimeter, more preferably greater than 3. 8 grams / cubic centimeter, preferably greater than 3. 9 grams / cubic centimeter, hardness is generally greater than 20Gpa.
  • Pure boehmite is a very fine-grained powdery material. The price is very high. The cost of ⁇ -alumina-based ceramic abrasives prepared with pure boehmite is also high. When manufacturing ceramic abrasives, pure bo Mushi raw materials account for the largest proportion of costs and are the most important part of the price of ceramic abrasives. The price of ceramic abrasives is 15 to 30 times that of ordinary abrasives. Although it has better performance than ordinary abrasives, it also seriously affects the popularity and application of such abrasives. How to reduce the manufacturing cost of ceramic abrasives and make ceramic abrasives It is of great significance to get a wider range of applications.
  • the object of the present invention is to solve the problem of preparing ceramic abrasives in the prior art, using pure boehmite as a main raw material and high cost, and providing a low-cost boehmite semi-finished product as a main raw material, which is prepared by a sol-gel method. ⁇ -alumina based abrasive and preparation method thereof.
  • the granules of the granules are at 0.15 g/cm 3 , the microhardness is greater than 20 GPa, and the crystal grains of the granules are at 0.15. Micron ⁇ 0. 3 microns between.
  • a method for preparing an ⁇ -alumina based abrasive characterized in that the steps are as follows:
  • the sifted granules are placed in a kiln for calcination.
  • the furnace temperature is controlled at 500 ° C ⁇ 800 ° C, the calcination time is 10 ⁇ 60 minutes, after calcination, the granules are sintered, and the furnace temperature is controlled to 1300 ° C. ⁇ 1400'C, sintering time 5 ⁇ 60 minutes.
  • the dilute nitric acid when dilute nitric acid is added to the slurry, all the dilute nitric acid is placed in one time, so that the pH of the slurry is 1.5 to 2, and the sol and the gel are gradually formed by stirring under vacuum.
  • the small particles can be separated by sedimentation (or other physical separation methods such as filtration through a mesh of mesh):
  • the small particles may be separated by sedimentation (or other physical separation methods such as filtration through a mesh of mesh):
  • the above method must be formulated to dilute the slurry concentration. If you follow normal boehmite For solids calculation, the solid content is preferably not more than 25%.
  • the pH of the slurry is adjusted to 4 with dilute nitric acid, the viscosity of the slurry is the lowest, placed for 60 minutes, the upper liquid is taken, and the upper liquid is taken under vacuum. In the case, acid is added for the next preparation.
  • a magnesium nitrate solution is added before the gel is formed, and the amount of magnesium nitrate added is 0.6% to 3.2% of the total amount of alumina in the raw material. Adding a solution of magnesium nitrate will result in better sintering of the product.
  • the boehmite semi-finished product contains 70% ⁇ 80% of the total water, and after the water is completely removed, the alumina content is more than 99%. After the semi-finished product of the boehmite is made into a normal product, the specific surface area is more than 250. Square meter / gram, grain size less than 10 nanometers.
  • the boehmite made of semi-finished products of boehmite needs to be added in two steps. It is preferred to remove up to 50% of the water. After removing the water, it must be crushed, sieved, and dedusted during the crushing process. A large amount of energy is lost, which also causes dust pollution and material loss.
  • the boehmite finished product formed by the above treatment has a high price, and the boehmite semi-finished product is used as a raw material, and the above steps are not required, the price is low, and the moisture in the raw material is fully utilized, and almost no additional water or a small amount of water is added, and the formed colloid is even and delicate. Better gel and transparency, which is beneficial for the sintering of the final product.
  • step 1) of the present invention pure water may not be added.
  • the high-speed vacuum mixer cannot be used, and only a low-speed vacuum mixer or kneader with a large stirring torque can be used.
  • the agitator of the present invention may be replaced by a mixer, a kneader or the like having a vacuuming function.
  • the amount of seed crystal added is 0.6% to 2% of the alumina content of the raw material.
  • the seed crystal may also be a substance containing an iron oxide source, and the iron oxide source includes a combination of one or more of ⁇ -iron oxide, a-FeOOH, ⁇ -iron oxide and ⁇ -FeOOH, and suitable iron oxide source includes Any substance that can be converted to alpha-iron oxide after heating.
  • the fine material under the 120 mesh sieve in the step 3) of the present invention can be continuously used as a raw material in the step 1).
  • step 4) of the present invention it is preferred to use a rotary kiln for calcination, or a calcination furnace for other forms.
  • the rate of temperature rise does not exceed 30 ° C / min.
  • the particles can be fed into another rotary kiln for sintering. It can also be sintered once in a high-temperature furnace, such as push-plate kiln or roller kiln.
  • Two holding zones are set in the high-temperature kiln, corresponding to the two steps of calcination and sintering, and the materials to be calcined by refractory enamel, ⁇ After entering the high temperature furnace, the crucible is sequentially passed through the calcination zone and the high temperature zone to complete calcination and sintering.
  • This type of high temperature furnace is more suitable for calcining and sintering the material under the 100 mesh screen.
  • the sintered product is further sieved to prepare a ceramic abrasive which meets the requirements of the abrasive product.
  • Granular sand The granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granules of the granule
  • the boehmite semi-finished product according to the present invention refers to the production of aluminum in the production of industrial products, such as boehmite (also known as boehmite), using aluminum ore or other raw materials capable of producing sodium metasilicate or sodium aluminate.
  • boehmite also known as boehmite
  • the produced suspension is formed into a semi-finished product of boehmite after drying or removing other water by pressure filtration or other means (after drying, Broken and sifted is a boehmite for industrial products. Contains 70% ⁇ 80% of total water.
  • the silicon oxide content is generally less than 0.5%, and the sodium oxide is generally less than 0.15%, containing a small amount of iron oxide and other impurities, and the rest is alumina.
  • the specific surface area is more than 250 m 2 /g, and the grain size is less than 10 nm.
  • the invention has the advantages of low raw material cost and stable process and mature, and the ⁇ -alumina-based abrasive prepared by the invention can be used for the fixed abrasive, the coated abrasive and other abrasive products, and the prepared abrasive product has the grinding. High cutting efficiency, self-sharpness and long durability.
  • Figure 1 is a SEM photograph of a cross section of the particles obtained in Example 2;
  • Figure 2 is a SEM photograph of the surface of the particles obtained in Example 2.
  • a 150-liter vacuum mixer In a 150-liter vacuum mixer, add 16.8 kg of purified water, 42 kg of 70% boehmite semi-finished product, 3 kg of alumina seed crystal slurry with a concentration of 4%, and stir the mixer to form a slurry, adding 20% concentration. After 1.6 kg of the nitric acid solution, it was stirred for 5 minutes. Stop stirring, input the slurry into the colloid mill, further refine the slurry. The slurry is ground from the colloid and transferred to the original mixer. Vacuum is applied, the mixer is started, 3 kg of 20% nitric acid is added, and 1 liter is added. An aqueous solution of magnesium nitrate hexahydrate is stirred well. At this point the gel has formed.
  • the gel prepared above was transferred into a stainless steel tray and placed in a 120-inch oven until the gel became brittle, cracked, and became a fragment having a diameter of about several millimeters to a dozen millimeters, and some particles would reach several centimeters.
  • the size of the pieces depends on the speed of drying. The faster the drying speed, the smaller the particles.
  • the dried pieces are further broken, and the required particle size is sieved as needed.
  • the material on the 25 mesh sieve and the 120 mesh sieve is generally taken for the next treatment.
  • the furnace temperature is controlled at 60 (TC), and the material is fed into the furnace tube for calcination, and the calcination time is 30 minutes.
  • the 600 ⁇ calcined material is fed into another rotary kiln, the furnace temperature is controlled to 1400 ⁇ , sintering is performed, and the sintering time is 10 minutes. Clock.
  • the sintered product is further sieved to prepare a ceramic abrasive grain sand that meets the requirements of the abrasive product.
  • the prepared 46 mesh particle size density is 3.92 g / cm 3 and the microhardness is 24 GPa, and the crystal grains constituting the ceramic microcrystalline abrasive grains are 0.3 ⁇ m.
  • a 150-liter vacuum mixer add 0.6 kg of purified water, 62.5 kg of 80% boehmite semi-finished product, 6 kg of alumina seed crystal slurry with a concentration of 4%, and stir the stirrer to stir the slurry into a slurry. After 1.6 kg of a 20% nitric acid solution, it was stirred for 5 minutes. Stop stirring, input the slurry into the colloid mill, further refine the slurry. The slurry is ground from the colloid and transferred to the original mixer. Vacuum is applied, the mixer is started, 3.2 kg of 20% nitric acid is added, and 1 liter is added to contain 17%. An aqueous solution of magnesium nitrate hexahydrate is stirred well. At this point the gel has formed.
  • the calcination temperature was controlled at 750 ° C, the calcination time was 15 minutes; the sintering temperature was 1330 ° C, and the sintering time was 20 minutes.
  • the obtained product has a density of 3.95 g/cm 3 and a microhardness of 23 GPa, and the crystal grains constituting the ceramic microcrystalline abrasive grains are 0.2 ⁇ m.
  • Figure 1 shows an SEM photograph of the cross section of the granulated product after it has been ground.
  • Figure 2 shows an SEM photograph of the surface of the granulated product after it has been ground.
  • the difference is calcination and sintering in a 24 meter long roller kiln
  • the calcination zone temperature is set at 700 ° C
  • the calcination time is 60 minutes
  • the sintering zone temperature is set at 1360 ° C
  • sintering The time is set at 60 minutes.
  • the obtained product has a density of 3.94 g / cm 3 , a microhardness of 20. 5 Gpa, a microhardness of 23 Gpa, and a crystal grain constituting the ceramic microcrystalline abrasive grains.
  • the product has a density of 3.90 g / cm 3 and a hardness of 24 GPa, and the crystal grains constituting the ceramic microcrystalline abrasive grains are 0.2 ⁇ m.
  • This embodiment is equivalent to the first three embodiments without adding purified water.

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  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Structural Engineering (AREA)
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Abstract

公开了一种α-氧化铝基磨料及其制备方法,该磨料的特征在于颗粒密度大于3.88克/立方厘米,显微硬度大于20Gpa,组成颗粒的晶粒在0.15微米〜0.3微米之间。其制备方法的步骤如下:1)在具有抽真空功能的搅拌机中加入纯净水、勃姆石半成品和氧化铝晶种研磨液,搅拌将原料打成料浆;2)在料浆中加入浓度为20%的稀硝酸,真空状态下逐步形成溶胶、凝胶;3)胶体在140°C以下烘干,破碎,筛分出120目筛上的颗粒;4)将筛分出的颗粒进行煅烧,煅烧后将颗粒进行烧结;5)筛分出成品颗粒。该制备方法的原料成本低,工艺成熟稳定,利用该方法制得的磨料颗粒所制作的磨料制品的磨削效率高,自锐性好,耐用度长。

Description

说明 书 一种 α -氧化铝基磨料及其制备方法 技术领域
本发明属于 α -氧化铝陶瓷磨料颗粒及其制备方法领域,具体涉及一种低成本的 α -氧化铝 基磨料及其制备方法。
背景技术
熔胶凝胶法制备陶瓷磨料的一般方法是用纯净的勃姆石与去离子水、 晶种和硝酸混合生 成均匀细腻的溶胶或凝胶, 然后干燥, 去除凝胶体中的水分, 再把干燥的凝胶大颗粒破碎成 比所需尺寸略大的颗粒, 然后, 在 500°C~800°C温度下煅烧, 再在 1300°C~1500°C温度下煅烧 5〜60分钟, 形成氧化铝的坚硬烧结体, 烧结好的磨料颗粒密度一般大于 3. 5克 /立方厘米, 更好的大于 3. 8克 /立方厘米, 最好大于 3. 9克 /立方厘米, 硬度一般大于 20Gpa。
纯净的勃姆石是一种粒度很细的粉状物料,价格很高,用纯净的勃姆石制备的 α -氧化铝 基陶瓷磨料的成本也很高, 在制造陶瓷磨料时, 纯净的勃姆石原料所占的成本比例最大, 是 构成陶瓷磨料价格的最主要部分。陶瓷磨料的价格是普通磨料价格 1 5 ~ 3 0倍,虽然具有比 普通磨料更优良的性能, 但也严重影响了该种磨料的普及和应用, 研究如何降低陶瓷磨料的 制造成本, 使陶瓷磨料得到更广泛的应用, 具有重要的意义。
多年来, 为了提高氧化铝基磨料的磨削性能, 人们发明了各种办法, 如为了提高白刚玉 的韧性和磨削性能, 可在冶炼刚玉时添加氧化铬、 氧化钒和氧化锆等金属氧化物, 也有通过 快速冷却的方法, 使之形成微晶结构来提高韧性; 或者两者都用。 这些方法在一定程度上提 高了磨料的韧性和磨削性能, 诞生了一些磨料的新品种, 如铬刚玉、 锆刚玉、 钒刚玉微晶刚 玉等等。 但这些性能的提高还不是很大, 在磨削上带来的好处有限。 上世纪 8 0年代, 人们 发明了溶胶凝胶法生产微晶陶瓷磨料的工艺, 如美国专利 Ν 4314827。 一般是用勃姆石为原 料, 利用溶胶凝胶技术, 制成氧化铝的溶胶凝胶, 然后干燥、 破碎、 烧结, 成为具有亚微米 结构的陶瓷磨料。由于具有细微的晶体结构,其晶粒大小比传统意义上的微晶刚玉要小得多, 再加上陶瓷磨料是破碎以后烧结, 避免了普通电熔刚玉破碎时造成的微裂纹, 使得溶胶凝胶 法制造的陶瓷磨料具有极优良的磨削性能。 后来, 人们为了进一步提高陶瓷磨料的技术质量 性能, 又进行了许许多多的工作, 如在制备溶胶时加入晶种, 既可降低烧结温度, 又使陶瓷 磨料的晶粒尺寸进一步缩小,从而提高了产品的磨削性能,如美国专利 Νο.4623364;还有在制 成干燥凝胶后, 先进行低温煅烧, 然后用镁、 钴、 钇、 稀土元素等的硝酸盐溶液进行浸泽, 再干燥烧结, 也能提高产品性能, 这方面的专利如美国专利 Νο.5776214。 这些方法虽然提高
1
确 认 本 了陶瓷磨料的性能, 但也增加了生产工序。 提髙了生产成本, 制约了该产品应用的普及。 发明内容
本发明的目的是解决现有技术制备陶瓷磨料, 采用纯净的勃姆石为主要原料, 成本高的 缺陷, 提供一种使用成本低的勃姆石半成品为主原料, 通过溶胶凝胶法来制备 α -氧化铝基磨 料及其制备方法。
本发明是通过如下技术方案来实现的- 即一种 α -氧化铝基磨料, 其特征在于颗粒密度大于 3. 88 克 /立方厘米, 显微硬度大于 20Gpa,组成颗粒的晶粒在 0. 15微米〜 0. 3微米之间。
一种 α -氧化铝基磨料的制备方法, 其特征在于步骤如下:
1 )在具有抽真空功能的搅拌机中加入纯净水、勃姆石半成品和氧化铝晶种研磨液,开动 抽真空搅拌机搅拌, 把原料打成均匀料浆, 所述纯净水的加入量为勃姆石半成品原料量的 1%~40%, 氧化铝晶种研磨液的浓度为 4%, 晶种的加入量是原料中氧化铝含量的 0.6%^%。
2)在料浆中加入 20%稀硝酸, 使料浆的 ΡΗ值 =1.5~2, 真空状态下搅拌, 料浆逐歩形成 溶胶、 凝胶。
3 )搅拌均匀后, 放掉真空, 取出胶体, 在不高于 140°C温度下烘干, 破碎, 筛分出 120 目筛上的颗粒。
4)将筛分出的颗粒放入窑炉中进行煅烧, 炉温控制在 500°C~800'C, 煅烧时间为 10~60 分钟, 煅烧后将颗粒进行烧结, 炉温控制至 1300°C~1400'C, 烧结时间 5~60分钟。
5)筛分出成品颗粒。
作为本发明的一个优选方案: 在料浆中加入稀硝酸时, 一次性放入全部稀硝酸, 使料浆 的 PH值 =1.5~2, 抽真空状态下, 搅拌逐步形成溶胶、 凝胶。
采用上述方法, 料浆中会有少量的打不开的小颗粒, 最终烧结出的磨料会含有白点, 对 产品质量有一定的影响, 但这类产品在某些场合不影响使用。
当需要清除上述小颗粒时,可以用沉降(或其它物理分离方法如用一定筛孔的筛网过滤) 的方法把小颗粒分离出来:
作为本发明的一个优选方案: 当料桨中勃姆石的固含量不大于 25%时, 先用一部分稀硝 酸, 使料浆的 PH值 =4, 放置 60分钟, 取上部液体, 在抽真空的情况下, 在取出的上部液体 中再次加入稀硝酸,同时开动搅拌机搅拌,使料浆的 PH值 =1.5~2,料浆逐步形成溶胶、凝胶。
当需要清除上述小颗粒时,可以用沉降(或其它物理分离方法如用一定筛孔的筛网过滤) 的方法把小颗粒分离出来: 上述方法必须把料浆浓度配制的比较稀。 如果按正常的勃姆石作 为固体计算的话, 其固含量最好不大于 25%, 用稀硝酸把料浆的 PH值调到 4时, 料浆的黏 度最低,放置 60分钟,取上部液体,取上部液体在抽真空的情况下,加酸进行下一步的制备。
作为本发明的一个优选方案: 在料浆中加入稀硝酸时, 先放入一部分稀硝酸, 使料浆的 PH值 =4, 停止搅拌, 把料浆输入胶体磨, 进一步细化料浆, 把细化的料浆转回原搅拌机中, 在抽真空的状态下, 加入稀硝酸, 同时开动搅拌机搅拌, 使料浆的 PH值 =1.5~2, 料浆逐步形 成溶胶、 凝胶。
作为本发明的一个优选方案: 料浆形成溶胶后, 变成凝胶前, 加入硝酸镁溶液, 硝酸镁 的加入量为原料中氧化铝总量的 0.6%~3.2%。 加入硝酸镁溶液会使产品烧结的更好。
作为本发明的一个优选方案: 勃姆石半成品含总水量 70%~80%, 所含的水全部去掉后, 氧化铝含量大于 99%, 薄姆石半成品制成正常产品后, 比表面积大于 250平方米 /克, 晶粒度 小于 10纳米。
由勃姆石半成品制成工业品勃姆石,需要增加两步工序,首选去除多达 50%以上的水分, 去掉水分后, 还要破碎、 过筛, 在破碎中还要除尘, 整个过程消耗掉大量的能源, 还会造成 粉尘污染和物料损耗。 经过上述处理形成的勃姆石成品价格高, 采用勃姆石半成品为原料, 无需上述步骤, 价格低, 充分利用原料中的水分, 几乎不用再加水或少量的加水, 形成的胶 体均匀细腻, 成胶性和透明性更好, 有利用于最终产品的烧结。
本发明的步骤 1 ) 中, 纯净水也可以不加, 当加水少或不加水时, 不能使用高速抽真空 搅拌机, 只能使用搅拌力矩大的低速抽真空搅拌机或捏合机。 本发明中的搅拌机也可以采用 具有抽真空功能的混料机、 捏合机等装置来替换。
晶种的加入量是原料中氧化铝含量的 0.6%~2%。 晶种也可以是包含某种氧化铁源物质, 氧化铁源包括 α -氧化铁, a -FeOOH, γ -氧化铁和 γ - FeOOH中的一种或多种的组合, 合适 的氧化铁源包括任何一种在加热后可以转化为 α -氧化铁的物质。
本发明的步骤 3) 中 120目筛下的细料可以在步骤 1 ) 中作为原料继续使用。
本发明的步骤 4) 中优选采用回转窑来进行煅烧, 也可以在其它形式的煅烧炉上进行锻 烧。 用其它形式的煅烧炉煅烧时, 其升温速度不超过 30°C/分钟。 烧结时, 可以把颗粒输入 另一回转窑中进行烧结。 也可以在一个高温炉中一次烧结, 比如推板窑或辊道窑, 在高温窑 中设定两个保温区, 分别对应煅烧和烧结两个步骤, 用耐火匣钵装要煅烧的料, 匣钵进入高 温炉后,依次通过煅烧区和高温区,完成煅烧和烧结。用这类高温炉比较适合煅烧和烧结 100 目筛下的料。
本发明的步骤 5) 中烧结好地产品经进一步筛分, 制备出符合磨料制品要求的陶瓷磨料 粒度砂。制备的产品密度大于 3. 85克 /立方厘米,基本在 3. 8Γ3. 95之间;显微硬度大于 20Gpa, 组成陶瓷磨料颗粒的晶粒在 0. 5微米以下, 基本在 0. 15~0. 3微米之间。
本发明所述的勃姆石半成品是指在生产工业产品拟薄水铝石(又叫勃姆石)时, 以铝矿 石或其它能制造偏铝酸钠或铝酸钠的原料制造出偏铝酸钠溶液, 然后进行酸化、 纯化等一系 列工序后, 生产出的悬浮液, 在经压滤或其它手段去掉大部分水后, 形成的滤饼, 即为勃姆 石半成品 (烘干后, 破碎、 过筛即为工业产品拟薄水铝石)。 含总水量 70%~80%。 如果把所含 的水全部去掉后计算, 含氧化硅一般小于 0. 5%, 氧化钠一般小于 0. 15%, 含少量氧化铁等杂 志, 其余为氧化铝。勃姆石半成品制成正常产品后, 比表面积大于 250平方米 /克, 晶粒度小 于 10纳米。
本发明具有原料成本低、 工艺成熟稳定的优点, 利用本发明所制得的 α -氧化铝基磨料可 以用于固结磨具, 涂附磨具以及其它磨料制品中, 制作的磨料制品具有磨削效率高、 自锐性 好、 耐用度长的特点。
附图说明
图 1是实施例 2所得颗粒断面的 SEM照片;
图 2是实施例 2所得颗粒表面的 SEM照片。
具体实施方式
实施例 1
150升的抽真空搅拌机中, 加纯净水 16.8千克, 含水 70%勃姆石半成品 42千克, 浓度 4%的氧化铝晶种研磨液 3千克, 开动搅拌机搅拌打成料浆, 加入浓度为 20%硝酸溶液 1.6千 克后, 搅拌 5分钟。 停止搅拌, 把料浆输入胶体磨, 进一步细化料浆, 料浆从胶体磨出来后 转入原搅拌机中, 抽真空, 开动搅拌机, 加入 3千克 20%的硝酸, 再加入 1升含有 17%六水 硝酸镁的水溶液, 搅拌均匀。 此时凝胶已经形成。
把上述制备的凝胶转入不锈钢料盘中, 放入 120Ό的烘箱中, 直至凝胶变脆, 开裂, 成 为直径约几毫米至十几毫米的碎块, 有的颗粒会达到几个厘米, 碎块的大小取决于烘干的速 度。 烘干速度越快, 颗粒越小。
把烘干的碎块进一步破碎, 根据需要, 筛出需要的粒度。 作为磨料, 一般取 25目筛下、 120目筛上的物料进行下一步处理。
在一不锈钢炉管直径 120ram, 长 200mra的回转电窑, 炉温控制在 60(TC, 把料输入到炉管 中, 进行煅烧, 煅烧时间为 30分钟。
把在 600Ό煅烧的料输入另一回转窑中, 炉温控制至 1400Ό , 进行烧结, 烧结时间 10分 钟。
烧结好地产品经进一步筛分, 制备出符合磨料制品要求的陶瓷磨料粒度砂。制备的 46目 粒度颗粒密度为 3. 92克 /立方厘米,显微硬度 24Gpa,组成陶瓷微晶磨料颗粒的晶粒 0. 3微米。 实施例 2
150升的抽真空搅拌机中, 加纯净水 0.6千克, 含水 80%勃姆石半成品 62.5千克, 浓度 4%的氧化铝晶种研磨液 6千克, 开动搅摔机搅拌打成料浆, 加入浓度为 20%硝酸溶液 1.6千 克后, 搅拌 5分钟。 停止搅拌, 把料浆输入胶体磨, 进一步细化料浆, 料浆从胶体磨出来后 转入原搅拌机中, 抽真空, 开动搅拌机, 加入 3.2千克 20%的硝酸, 再加入 1升含有 17%六 水硝酸镁的水溶液, 搅拌均匀。 此时凝胶已经形成。
以下同实例 1所述, 煅烧温度控制在 750'C, 煅烧时间为 15分钟; 烧结温度为 1330°C, 烧结时间为 20分钟。 所得的产品密度 3. 95克 /立方厘米, 显微硬度为 23Gpa, 组成陶瓷微晶 磨料颗粒的晶粒 0. 2微米。
如图 1所示为颗粒制成磨制成品后断面的 SEM照片;如图 2所示为颗粒制成磨制成品后 表面的 SEM照片。
实施例 3
同实例 1所述,不同的是煅烧和烧结在一 24米长的辊道窑中,煅烧区温度设定在 700°C, 煅烧时间为 60分钟, 烧结区温度设定在 1360°C, 烧结时间设定在 60分钟。 所得的产品密度 3. 94克 /立方厘米, 显微硬度为 20. 5Gpa, 显微硬度为 23Gpa,组成陶瓷微晶磨料颗粒的晶粒
0. 4微米。
实施例 4
在 30升带真空功能的捏合机中, 加入含水 75%勃姆石半成品 10千克, 浓度 4%的氧化铝 晶种研磨液 0. 4千克, 0. 48千克含有 17%六水硝酸镁的水溶液。 开动捏合机捏合 5分钟, 加 入浓度为 20%的硝酸 0.9千克, 继续开动捏合机捏合 60分钟, 然后, 取出烘干, 以下同实例
1。 所得产品密度 3.90克 /立方厘米, 硬度 24Gpa, 组成陶瓷微晶磨料颗粒的晶粒 0. 2微米。
本实施例相当于前 3个实施例, 不加纯净水。

Claims

权 利 要 求 书
1、 一种 α -氧化铝基磨料, 其特征在于陶瓷磨料颗粒密度大于 3. 88克 /立方厘米, 显微 硬度大于 20Gpa,组成陶瓷磨料颗粒的晶粒在 0. 15微米 ~0. 3微米之间。
2、 一种 α -氧化铝基磨料的制备方法, 其特征在于步骤如下-
1 )在具有抽真空功能的搅拌机中加入纯净水、勃姆石半成品和氧化铝晶种研磨液, 开动 抽真空搅拌机搅拌, 把原料打成均匀料浆, 所述纯净水的加入量为勃姆石半成品原料量的 1%〜40%, 氧化铝晶种研磨液的浓度为 4%, 晶种的加入量是原料中氧化铝含量的 0. 6%〜2%;
2)在料浆中加入浓度为 20%的稀硝酸, 使料浆的™值 =1. 5~2, 真空状态下搅拌, 料桨 逐步形成溶胶、 凝胶;
3)搅拌均匀后, 放掉真空, 取出胶体, 在 140°C以下烘干, 破碎, 筛分出 120目筛上的 颗粒;
4)将筛分出的颗粒放入窑炉中进行煅烧, 炉温控制在 500°C~800'C, 煅烧时间为 10~60 分钟, 煅烧后将颗粒进行烧结, 炉温控制至 1300TTl40(TC, 烧结时间 5~60分钟;
5)筛分出成品颗粒。
3、 根据权利要求 2所述的 α -氧化铝基磨料的制备方法, 其特征在于在料浆中加入稀硝 酸时, 一次性放入全部稀硝酸, 使料浆的 ΡΗ值 =1. 5〜2, 抽真空状态下, 搅拌逐步形成溶胶、 凝胶。
4、 根据权利要求 2所述的 a -氧化铝基磨料的制备方法, 其特征在于当料浆中勃姆石的 固含量不大于 25%时, 先用一部分稀硝酸, 使料浆的 ΡΗ值 =4, 放置 60分钟, 取上部液体, 在抽真空的情况下, 在取出的上部液体中再次加入稀硝酸, 同时开动搅拌机搅拌, 使料浆的 值 =1. 5~2, 料浆逐步形成溶胶、 凝胶。
5、 根据权利要求 2所述的 a -氧化铝基磨料的制备方法, 其特征在于在料浆中加入稀硝 酸时, 先放入一部分稀硝酸, 使料浆的 ΡΗ值 =4, 停止搅拌, 把料浆输入胶体磨, 进一步细化 料浆, 把细化的料浆转回原搅拌机中, 在抽真空的状态下, 再次加入稀硝酸, 同时开动搅拌 机搅拌, 使料浆的 ΡΗ值 =1. 5〜2, 料浆逐步形成溶胶、 凝胶。
6、 根据权利要求 2或 3或 4或 5所述的 α -氧化铝基磨料的制备方法, 其特征在于料浆 形成溶胶后, 变成凝胶前, 加入硝酸镁溶液, 硝酸镁的加入量为是原料中氧化铝总量的 0. 6%〜3. 2%。
7、 根据权利要求 2所述的 α -氧化铝基磨料的制备方法, 其特征在于勃姆石半成品含总 水量 70%〜80%, 所含的水全部去掉后, 氧化铝含量大于 99%, 薄姆石半成品制成正常产品后, 比表面积大于 250平方米 /克, 晶粒度小于 10纳米。
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CN116462490B (zh) * 2023-04-27 2023-12-12 无锡成旸科技股份有限公司 一种高硬度氧化铝研磨粉及其制备方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1046924A (zh) * 1989-04-28 1990-11-14 诺顿公司 含有烧结的可溶凝胶氧化铝磨料的粘结磨料制品
CN1086201A (zh) * 1992-10-23 1994-05-04 日本研磨材工业株式会社 陶瓷磨粒料及其制造方法和磨削制品
CN1188465A (zh) * 1995-06-20 1998-07-22 美国3M公司 含有二氧化硅和氧化铁的α氧化铝基磨料颗粒
CN1192229A (zh) * 1995-07-26 1998-09-02 圣戈本工业陶瓷股份有限公司 改进的溶胶-凝胶法氧化铝磨料

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4314827A (en) * 1979-06-29 1982-02-09 Minnesota Mining And Manufacturing Company Non-fused aluminum oxide-based abrasive mineral
DE69002557T2 (de) * 1989-02-01 1993-12-23 Showa Denko Kk Keramik aus aluminiumoxyd, schleifmittel und deren verfahren zur herstellung.
JP2779041B2 (ja) * 1990-04-04 1998-07-23 株式会社ノリタケカンパニーリミテド 酸化クロムを添加した微結晶構造アルミナ焼結研摩材及びその製法
DE4113476A1 (de) * 1991-04-25 1992-10-29 Huels Chemische Werke Ag Polykristalline, gesinterte schleifkoerner auf basis von alpha-al(pfeil abwaerts)2(pfeil abwaerts)o(pfeil abwaerts)3(pfeil abwaerts), verfahren zu ihrer herstellung und deren verwendung
US5387268A (en) * 1991-10-16 1995-02-07 Showa Denko Kabushiki Kaisha Sintered alumina abrasive grain and abrasive products
US5527369A (en) * 1994-11-17 1996-06-18 Saint-Gobain/Norton Industrial Ceramics Corp. Modified sol-gel alumina
JP4021080B2 (ja) * 1998-11-27 2007-12-12 花王株式会社 研磨液組成物
NL1014513C2 (nl) * 2000-02-28 2001-08-29 Dsm Nv Polymeersamenstelling bevattende een semi-kristallijn of glasvormend polymeer in een stijve fase en, als slagvastheidsverbeteraar daarin, een rubberachtig polymeer in een disperse fase.

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1046924A (zh) * 1989-04-28 1990-11-14 诺顿公司 含有烧结的可溶凝胶氧化铝磨料的粘结磨料制品
CN1086201A (zh) * 1992-10-23 1994-05-04 日本研磨材工业株式会社 陶瓷磨粒料及其制造方法和磨削制品
CN1188465A (zh) * 1995-06-20 1998-07-22 美国3M公司 含有二氧化硅和氧化铁的α氧化铝基磨料颗粒
CN1192229A (zh) * 1995-07-26 1998-09-02 圣戈本工业陶瓷股份有限公司 改进的溶胶-凝胶法氧化铝磨料

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114752352A (zh) * 2022-04-13 2022-07-15 河南天马新材料股份有限公司 一种高自锐性氧化铝磨料粉体及制备方法
CN115557776A (zh) * 2022-09-26 2023-01-03 安徽铁创新材料科技有限公司 高强度复合轮轨增粘陶瓷粒子的制备方法、装置及应用
CN115557776B (zh) * 2022-09-26 2023-05-09 安徽铁创新材料科技有限公司 高强度复合轮轨增粘陶瓷粒子的制备方法、装置及应用

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