CN1410502A - Cerium series abrasive material and analyzing method thereof - Google Patents
Cerium series abrasive material and analyzing method thereof Download PDFInfo
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- CN1410502A CN1410502A CN02143936.2A CN02143936A CN1410502A CN 1410502 A CN1410502 A CN 1410502A CN 02143936 A CN02143936 A CN 02143936A CN 1410502 A CN1410502 A CN 1410502A
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Abstract
The present invention relates to a cerium polishing material comprises a rare earth oxide obtained by roasting a rare earth compound, characterized in that the raw material for the cerium polishing material comprises at least any one element of silicon, aluminum and zirconium and a particulate substance without solubility in an aqueous solution of perchloric acid and an aqueous solution of hydrogen peroxide. The content of the particulate substance is <=200 ppm expressed in terms of weight ratio.
Description
Technical field
The present invention relates to cerium is that abrasive material raw material and cerium are the analytical procedure of abrasive material raw material.The less cerium of content that relates more specifically to the gritty particle of meeting generation cut is the abrasive material raw material and judges whether it is that aforementioned cerium is the analytical procedure of abrasive material raw material.
Background technology
Cerium is the grinding that abrasive material is used to various glass materials.Particularly also be used for the grinding of magnetic recording medium such as hard disk with the used glass material of glass, liquid-crystal display (LCD) glass substrate and so on electric electronic Instrument in recent years, its Application Areas constantly enlarges.
This cerium is that abrasive material is by the cerium oxide (CeO as principal constituent
2) abrasive particle that forms of particle and other rare earth metal oxide particles forms.In addition, cerium is the manufacture method of abrasive material, at first be with raw material pulverizing, add the fluoridation of fluorine composition then, and remove the alkali-metal chemical treatment (wet processing) in the raw material that can cause the abnormal grain growth with mineral acid, then, raw material after the wet processing is filtered, after the drying, again through the heat roasting, makes sintering between the raw material particle, pulverizing, classification can make the abrasive material with required particle diameter and size-grade distribution once more.
As cerium is the abrasive material raw material, mostly uses the such natural matter of selecting from a kind of rare earth ore that is hamartite of bastnaesite concentrate in the past.Then use recently by hamartite and comparatively cheap in the rare-earth compounds that obtains of homemade complicated ore, it is carried out roasting, with a part or most of raw material wherein as rare earth oxide.This raw material that contains rare earth oxide is the dissolving ore, carry out chemical treatment, under the temperature more than 500 ℃, be that the rare-earth compounds of principal constituent carries out roasting then, be transformed into rare earth oxide from carbonated rare earth and obtain the carbonated rare earth that increases with rare earth metal concentration.Can regulate rare earth oxide content by adjusting conditions such as roasting time.
But not only cerium is an abrasive material, and all abrasive materials all require can obtain high-precision abrasive surface under the prerequisite of not damaging abrasive surface.At cerium in the past is in the manufacturing process of abrasive material, all to the adjustment of the size-grade distribution of abrasive particle and particle diameter, remove thick polishing particles, the cerium that do not manufacture existing grinding damage is that abrasive material has carried out a large amount of tests.
It is generally acknowledged the characteristic of using any raw material all can influence abrasive material greatly.But, all be to carry out mostly at present at the productivity of operability, cost, abrasive material etc. for the research of raw material, seldom study abrasive characteristic when doing abrasive material with it at raw material itself.In addition, for the appraisal procedure of gained raw material, also just composition analysis is usually studied the possibility of abrasive material generation cut seldom specially.
In recent years, along with the high precision int and the precise treatment of used substrates such as the densification of recording mediums such as hard disk, LCD, the abrasive material that uses when used glass material is ground also requires to have higher grinding precision.And, it is generally acknowledged that to the cerium that is applicable to these purposes be abrasive material, depend merely on the management and the improvement of manufacturing process, its effect is limited, also needs just to set about improving from feed stage.
The present invention just is being based on the invention that above background is finished, and it is the abrasive material raw material that its purpose just provides a kind of cerium that is applicable to that does not produce cut as abrasive material the time, and the analytical procedure that can determine this abrasive material is provided simultaneously.
Summary of the invention
As mentioned above, the means that improve the abrasive material property of raw material have two kinds, and a kind of is size-grade distribution and the particle diameter of adjusting abrasive particle, and another kind is to remove thick polishing particles.The present inventor finds to determine that cerium is the abrasive material factor that produces cut except the existence of the distribution of abrasive size and thick polishing particles, also comprises than by the existence of the higher particle of the hardness of abrasive substance.The present inventor finds that also the influence of this hard particles is not by due to its particle diameter, even if particulate also can produce cut.
Therefore, the present inventor studies at the generation factor and the composition of this hard particles, the result shows that these hard particles are to sneak in the manufacturing processed of abrasive material raw material, especially when dry, roasting rare earth compounds, sneak into because of the constituent material efflorescence of drying oven, stoving oven, roasting vessel etc.In addition, about its composition,, found to contain the composition that silicon contained in the refractory materials as the stoving oven constituent material, aluminium, zirconium composition and they change and produce because of heating when roasting though do not get clear as yet.In addition, can confirm that through the more detailed research of present inventor high chloro acid solution and aqueous hydrogen peroxide solution that this hard particles rare earth oxide and carbonated rare earth are insoluble to as solubility solution exist.
The present inventor confirms from aforementioned result of study, and can form the cerium that does not have the high precision abrasive surface that grinds cut is that the abrasive material raw material should be the material that does not contain aforementioned hard particles, and studied the relation with the content of hard particles, thereby finished the present invention.
That is to say, the present invention is that a kind of cerium that contains the rare earth oxide that obtains by the roasting rare earth compounds is the abrasive material raw material, the feature of this raw material is, contain at least a kind of element that is selected from silicon, aluminium, zirconium, and contain the saccharoid that is insoluble to high chloro acid solution and aqueous hydrogen peroxide solution, the content of aforementioned saccharoid in weight ratio below 200ppm.
Among the present invention, " contain at least a kind of element that is selected from silicon, aluminium, zirconium; and contain the saccharoid that is insoluble to high chloro acid solution and aqueous hydrogen peroxide solution " be based on present inventor's result of study, in order to carry out possible qualification to producing the hard particles that grinds cut.That is to say that in the abrasive material raw material that obtains at the roasting rare earth compounds, though contain elements such as silicon, aluminium, zirconium, producing cut is the saccharoid that contains these elements, and is the saccharoid of hardization, this point is very clear and definite.Meanwhile, even if because contain elements such as silicon, aluminium, zirconium, but high chloro acid solution and aqueous hydrogen peroxide solution are had solvability, it just can not become and produces the reason of grinding cut, so this have deliquescent material and should foreclose.
On the other hand, why being set in below the 200ppm about the content of hard particles, is because the grinding rate when considering as abrasive material and produce the degree of cut, and regulation does not have the amount of the hard particles of the anxiety that produces cut in the grinding rate scope that adopts usually.That is to say that the generation of grinding cut also is subjected to the influence of grinding rate, under the high situation of grinding rate, how much has some hard particles in the abrasive material, will produce the grinding cut, but this grinding cut can be removed at short notice by grinding at a high speed.But the high speed grinding that aforementioned phenomenon in fact occurs is impossible.Under the industrial the fastest grinding rate that can realize (0.01~0.5 μ m/min), the content that does not produce the hard particles in the raw material of cut must be below 200ppm.
Therefore, cerium of the present invention is because of the hard particles that produces of sneaking into of the constituent material of stoving oven etc. in the time of should getting rid of drying at aforementioned rare-earth compounds, roasting in the abrasive material raw material.Therefore, cerium of the present invention is that the abrasive material raw material can make by the sneaking into of constituent material of suppressing this stoving oven etc.Cerium of the present invention is that the manufacture method of abrasive material raw material is as described below, and promptly starting material adopt ores such as hamartite and middle home-made complicated ore, with dissolvings such as hydrochloric acid, make it precipitation with carbonate again, filtration washing obtains rare-earth compounds (carbonated rare earth) then, again drying and roasting and make.Among the present invention, aforementioned operation is carried out following improvement just can get rid of hard particles.
At first, when the rare-earth compounds that washing obtains with carbonate deposition, must be washed till fluorine concentration reach enough hang down till.This is to consider if under the state residual from raw-material fluorine compositions such as hamartites, dry, roasting starting material, this fluorine becomes branch to volatilize with hydrofluoric form, corrodes the constituent material of drying oven and stoving oven, thereby becomes the reason of sneaking into hard particles.And in this clean operation, fluorine concentration is best with 0.1~0.01 weight % that is washed till with respect to raw-material weight.
In addition, in the drying after cleaning, the calcining process, drying is preferably in 100~150 ℃ the scope carries out.In this temperature range, the fluorine composition in the rare-earth compounds is difficult to be transformed into hydrogen fluoride, so can control in the drying process erosion to stove.In addition, in calcining process, maturing temperature preferably is set between 400~800 ℃.Temperature is set in and can makes carbonated rare earth be oxidized to rare earth oxide more than 400 ℃, is being that fluorine composition in order to suppress in the rare-earth compounds is transformed into hydrogen fluoride below 800 ℃.In addition, in calcining process, also can suppress sneaking into of hard particles by selecting different stoving ovens.That is to say that the continous way kiln resemble the rotary kiln is compared with step static stove, stove body temperature changes little, and thermal shocking is also smaller, so can suppress the efflorescence of body of heater and sneaking into of hard particles.
In addition, sneak in the abrasive material raw material in order to prevent hard particles more effectively, the hard refractory materials of the most handy anti-erosion, difficult disintegration is made drying oven, stoving oven and roasting vessel etc., and uses these equipment to carry out drying and roasting.For example, the part that contacts with the abrasive material raw material of body of heater is made with the thermotolerance metallic substance of stainless steel and so on, can suppress the erosion and the disintegration of body of heater by using alumina content height, material that resistivity against fire is high.
But the cerium that the present inventor makes is that the hard particles that contains in the abrasive material raw material is insoluble to high chloro acid solution and aqueous hydrogen peroxide solution.Therefore, the abrasive material raw material that the present inventor utilizes this characteristic to find to make for any method can both be to it produces the method that the possibility of cut is assessed during as abrasive material.
This analytical procedure is to be the method that the abrasive material raw material is analyzed to the cerium that contains the rare earth oxide that gets by the roasting rare earth compounds, and this method is made up of following each operation:
(a) cerium after the roasting is the operation that abrasive material feedstock capture sample carries out weighing,
(b) in aforementioned sample, add high chloro acid solution and aqueous hydrogen peroxide solution, the operation that the solution after adding is heated again,
(c) operation of the solution after the filtering and heating,
(d) weight of the residue after measure filtering is calculated the ratio of the weight and the residue weight of aforementioned test portion.
This analytical procedure is to get the abrasive material raw material to be checked of any amount, and it is contacted with aqueous hydrogen peroxide solution with the high chloro acid solution, and from wherein extracting hard particles, quantitative analysis goes out the method for the content of hard particles in the abrasive material raw material.
Below this analytical procedure is specifically described.At first, get cerium that the process regulation operation of any amount makes and be the abrasive material raw material as sample, and weighing ((a) operation).If take all factors into consideration the hard particles amount and be trace with this 2 point of analysis efficiency, then institute's amount of materialsing is advisable about with 10~500g.
Then, add high chloro acid solution and aqueous hydrogen peroxide solution, reheat in the abrasive material raw material after weighing.Main component dissolvings such as the rare earth oxide in the abrasive material raw material, carbonated rare earth like this, hard particles stays ((b) operation) as residue and residual.At this moment, that dissolve abrasive material raw material (carbonated rare earth, rare earth oxide) mainly is the high chloro acid solution, and aqueous hydrogen peroxide solution plays the effect of solubility promoter, especially can make the cerium in the abrasive material raw material remain on 3 valency states with high resolution.High chloro acid solution's concentration is preferably 5~20 weight %.When dissolving the abrasive material raw material efficiently, also to consider the waste problem of reagent.In addition, because aqueous hydrogen peroxide solution plays solubility promoter, so preferably working concentration is the solution of 0.1~5 weight %.In addition, there is no particular limitation to the interpolation of high chloro acid solution and aqueous hydrogen peroxide solution order, and which kind of adds earlier all concern not quite.On the other hand, in this operation, heating after solution mixes is in order to promote the dissolving of abrasive material raw material, and this temperature is set in more than 80 ℃, below the boiling point of mixing solutions (90 ℃).
Then, the solution that has dissolved the abrasive material raw material is filtered, reclaim hard particles ((c) operation).Filter the preferably strainer (sieve) of aperture 0.3~5 μ m of filter material used in the operation at this.
Through above operation, measure the weight of the hard particles that reclaims, calculate the weight ratio with sample, can obtain cerium and be the hard particles content ((d) operation) in the abrasive material raw material.Then, just can judge that from the hard particles content of aforementioned acquisition it is the suitability of abrasive material raw material as cerium.
Have multiple working procedure although above-described cerium is the analytical procedure of abrasive material raw material, the operation of each operation all is not difficult, and also is easier analytical procedure on the whole.Therefore, according to this analytical procedure, can simply assess the quality that the cerium that is made by any means is the abrasive material raw material (whether contain and to produce the material that grinds cut).
Description of drawings
Fig. 1 is that the cerium of present embodiment is the simple flow chart of the analytical procedure of abrasive material raw material.
Embodiment
Preferred forms of the present invention below is described.
With the rare earth ore is starting material, with its dissolving, is transformed into carbonated rare earth, clean to fluorine content and be lower than 0.1 weight %, the starting material after will cleaning again carry out drying, and placing with alumina content is in the rotary kiln that makes of the stove material of 99 weight %, 600 ℃ of following roastings, make 6 kinds of abrasive material raw materials.In addition,, use identical raw material,, be transformed into carbonated rare earth, clean to fluorine content and be lower than 0.5 weight %, after the drying, place and leave standstill in the stove,, make 3 kinds of abrasive material raw materials 600 ℃ of following roastings with its dissolving as comparative example in contrast.
Then, by operation shown in Figure 1, measure the hard particles content in these abrasive material raw materials.Among Fig. 1, take by weighing each abrasive material raw material 50g as sample, add after the water 1000ml in this sample, add the high chloro acid solution 300ml of 60 weight % and the aqueous hydrogen peroxide solution 20ml of 30 weight % again, heating is boiled this mixing solutions and is risen 5 minutes.Making solution after the heating slowly after the cooling, is that the strainer of 0.44 μ m filters by the aperture, reclaims sieve and goes up residue, clean, 100 ℃ dry down, measure its weight.Then, from then on residue (hard particles) weight is calculated hard particles content in each raw material.
Then, using these raw materials to make cerium is abrasive material.With abrasive material with raw material 3kg and pure water 3L place filling the wet-type ball mill (capacity 5Ll) of steel crushing medium of diameter 5mm pulverized 6 hours, make the slip that the powder of median size (microscratch method D50 (accumulative total 50% particle diameter)) 1 μ m is formed.Then, be 6% in order to make the fluorine concentration in the gained abrasive material, adding concentration in the slip of pulverizing is the ammonium fluoride solution of 1mol/L, obtains filter cake with pure water washing after-filtration again.Then, dry this filter cake, 900 ℃ of roastings 3 hours, crushing and classification once more, obtaining cerium is abrasive material.
Subsequently, be the assessment that abrasive material carries out the grinding test and the abrasive surface of glass material with the cerium that makes.This grinding test is that each abrasive material is dispersed in the water, the abrasive thick liquid of furnishing 10 weight %.The abrasive disk that makes with polyurathamc in this abrasive thick liquid is to as being ground by the blue glass of the φ 65mm of abrasive substance.Grinding condition is: abrasive thick liquid is for slurry speed 5L/min, to the pressure 4.9 * 10 of abrasive surface
3The speed of rotation 120rpm of Pa, shredder.In addition, in grinding test, this abrasive thick liquid will often stir with stirrer, does not allow the abrasive material sedimentation.Glass material after the grinding is cleaned with pure water, and is dry under dustless state.
The assessment of abrasive surface is no marking to be arranged and use AFM (atomic force microscope) to measure the surfaceness of the arbitrary face (2 μ m * 2 μ m) of abrasive surface by observing abrasive surface, assesses according to its maximum value Rmax again.Have or not with abrasive particle that to remain in abrasive surface be that benchmark is assessed.Abrasive surface has definite method of no marking as described below.Promptly at the glass surface of abrasive surface, shine with the halogen lamp of 300,000 Luxs, with reflection method sight glass surface, identify the number and the degree (size) of cut, and fractionation, in the 100 branch modes that subtract that are divided into full marks, determine scoring.
The hard particles Determination on content result in the above raw material and the result of grinding test all are shown among the table 1.
Table 1
Hard particles content (ppm) | Grind cut | Rmax (dust) | |
??1 | ????148 | ????97 | ????60 |
??2 | ????77 | ????99 | ????52 |
??3 | ????22 | ????100 | ????48 |
??4 | ????3 | ????100 | ????35 |
??5 | ????4 | ????100 | ????33 |
??6 | ????9 | ????100 | ????42 |
Than 1 | ????616 | ????50 | ????470 |
Than 2 | ????888 | ????40 | ????530 |
Than 3 | ????1091 | ????40 | ????650 |
Can find out from table 1, hard particles content in the abrasive material raw material of embodiment is below 200ppm, the cerium of being made by these raw materials is that the grinding test of abrasive material does not see that almost cut produces, and the surfaceness (Rmax) of the abrasive material raw material of embodiment demonstrates the utmost point figure of merit below 60 dusts.In contrast, the surfaceness of the abrasive material raw material of comparative example is poor, and the abrasive surface after the grinding has cut to produce.
As mentioned above, cerium of the present invention is that the content that the abrasive material raw material will produce the hard particles of abrasive material cut is controlled within the specialized range.The cerium that the present invention can make the high precision flour milling that can form the no marking generation is an abrasive material.In addition, cerium of the present invention is that the analytical procedure of abrasive material raw material can determine the content that the cerium that is made by any manufacture method is the hard particles in the abrasive material easily.
Claims (5)
1. cerium is the abrasive material raw material, contain the rare earth oxide that obtains by the roasting rare earth compounds in the described raw material, it is characterized in that, contain at least a kind of element that is selected from silicon, aluminium, zirconium, and contain the saccharoid that is insoluble to high chloro acid solution and aqueous hydrogen peroxide solution, the content of aforementioned saccharoid in weight ratio below 200ppm.
2. cerium is the analytical procedure of abrasive material raw material, and described cerium is to contain the rare earth oxide that obtains by the roasting rare earth compounds in the abrasive material raw material, it is characterized in that, is made up of following operation:
(a) cerium after the roasting is the operation that abrasive material feedstock capture sample carries out weighing,
(b) in aforementioned sample, add high chloro acid solution and aqueous hydrogen peroxide solution, the operation that the solution after adding is heated again,
(c) operation of the solution after the filtering and heating,
The weight of the residue after (d) mensuration is filtered is calculated the weight of aforementioned test portion and the operation of residue weight.
3. cerium as claimed in claim 2 is the analytical procedure of abrasive material raw material, and its feature is that also high chloro acid solution's concentration is 5~20 weight %, and the concentration of aqueous hydrogen peroxide solution is 0.1~5 weight %.
4. be the analytical procedure of abrasive material raw material as claim 2 or 3 described ceriums, its feature also is, the Heating temperature of solution is more than 80 ℃, below the boiling point of this solution.
5. the analytical procedure that is the abrasive material raw material as each described cerium in the claim 2~4, its feature also be, filtering operation, to adopt the aperture be that the strainer of 0.3~5 μ m filters.
Applications Claiming Priority (2)
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JP2001302406 | 2001-09-28 | ||
JP2001302406A JP4237957B2 (en) | 2001-09-28 | 2001-09-28 | Quality evaluation method for cerium-based abrasive materials |
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CN1410502A true CN1410502A (en) | 2003-04-16 |
CN1162500C CN1162500C (en) | 2004-08-18 |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1849264B (en) * | 2003-09-12 | 2010-09-22 | 日立化成工业株式会社 | Cerium salt, process for producing the same, cerium oxide, and cerium-based abrasive material |
CN103923602A (en) * | 2013-01-15 | 2014-07-16 | 安阳市岷山有色金属有限责任公司 | Manufacturing method for cerium based abrasive material |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN102559064B (en) * | 2011-12-15 | 2014-01-29 | 上海华明高纳稀土新材料有限公司 | Cerium-zirconium praseodymium sosoloid and preparation method thereof |
-
2001
- 2001-09-28 JP JP2001302406A patent/JP4237957B2/en not_active Expired - Lifetime
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2002
- 2002-09-26 CN CNB021439362A patent/CN1162500C/en not_active Expired - Fee Related
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1849264B (en) * | 2003-09-12 | 2010-09-22 | 日立化成工业株式会社 | Cerium salt, process for producing the same, cerium oxide, and cerium-based abrasive material |
CN101885959B (en) * | 2003-09-12 | 2012-06-13 | 日立化成工业株式会社 | Cerium grinding agent |
CN103923602A (en) * | 2013-01-15 | 2014-07-16 | 安阳市岷山有色金属有限责任公司 | Manufacturing method for cerium based abrasive material |
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JP2003105326A (en) | 2003-04-09 |
JP4237957B2 (en) | 2009-03-11 |
CN1162500C (en) | 2004-08-18 |
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