1、Designation: C 690 09Standard Test Method forParticle Size Distribution of Alumina or Quartz Powders byElectrical Sensing Zone Technique1This standard is issued under the fixed designation C 690; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method, one of several found valuable for themeasurement of particle size, covers
3、the determination of theparticle size distribution of alumina or quartz powders (0.6 to56.0 m) using electrical sensing zone particle size analyzers.These instruments use an electric current path of small dimen-sions which is modulated by individual particle passagethrough an aperture, and produces
4、individual pulses of ampli-tude proportional to the particle volume.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety problems, if any, associated with its use. It
5、 is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Summary of Test Method2.1 A carefully dispersed, dilute suspension of the powderin a beaker filled with an electrolyte i
6、s placed on the instrumentsample stand. The suspension is forced through a restrictingaperture. Each particle passing generates an electric pulse thatis recorded on an electronic counter.2.2 The instrument response is essentially related to particlevolume (liquid displacement). Equivalent spherical
7、diameter iscommonly used to express the particle size. (Comparisons withother techniques have been found to be good for sphericalparticles; for non-spherical particles results may differ.)3. Significance and Use3.1 This test method is useful to both sellers and purchasersof alumina and quartz powder
8、s for determining particle sizedistributions for materials specifications, manufacturing con-trol, and development and research.4. Apparatus4.1 Electrical Sensing Zone Particle Counter.4.2 Aperture Tubes, diameter ranging from approximately30 to 140 m. The diameter required is dependent upon thepart
9、icle size distribution of the sample. Generally any giventube will cover a particle size range from 2 to 60 % of itsaperture diameter.NOTE 1In certain cases, apertures up to 300 m are usable.4.3 Sample Beaker, capable of maintaining all particlesuniformly in suspension (for example, round-bottom).4.
10、4 Blender, capacity 1-Lglass container.Ameans to controlspeed is required.4.5 Beakers, 100, 500, and 1000-mL.4.6 Pipet.4.7 Wash Bottles.4.8 Membrane Filtering Device, rated at 0.45-m filters orfiner.5. Reagents5.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise
11、indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available.2Other grades may beused, provided it is first ascertained that the reagent is ofsufficiently high purity t
12、o permit its use without lessening theaccuracy of the determination.5.2 Dispersing MediaTen percent solution of purified orreagent grade sodium hexametaphosphate in distilled watertwice filtered through the membrane filtering device.NOTE 2Deionized water may be substituted for distilled water.NOTE 3
13、This liquid should not be retained longer than 1 month andshould not be pH modified or heated.5.3 ElectrolyteDissolve 10.0 g of reagent grade sodiumchloride (NaCl) in 1000 mL of distilled water and filter twicethrough the membrane filtering device.5.4 Wash WaterDistilled water twice filtered through
14、 themembrane filtering device.1This test method is under the jurisdiction ofASTM Committee C21 on CeramicWhitewares and Related Products and is the direct responsibility of SubcommitteeC21.04 on Raw Materials.Current edition approved Feb. 15, 2009. Published February 2009. Originallyapproved in 1971
15、. Last previous edition approved in 1997 as C 690 03.2Reagent Chemicals, American Chemical Society Specifications , AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, VWR Inter
16、national Ltd., U.K., and the United States Pharmacopoeia,USPC, Rockville, MD1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.5 Calibration ParticlesNIST or NIST trace
17、able mono-sized particle standards.6. Procedure6.1 SummaryDisperse the test powder in the electrolytewith a blender. Transfer a representative portion to the samplebeaker that contains filtered electrolyte. Place sample beaker inthe apparatus and obtain particle size distribution in a chosensize ran
18、ge. Obtain relative weight fraction by assuming con-stant particle density.6.2 Precalibrate the aperture and electrolyte combinationfollowing the manufacturers instruction manual.NOTE 4Calibration should be performed in accordance with theinstruction manual. Monosized NIST or NIST traceable calibrat
19、ionstandards should be selected from Fig. A1.1. Mutual agreement on thesource and size of calibration standards is necessary for interlaboratorycomparisons.6.3 Check background counts by filling the sample beakerwith filtered electrolyte and taking counts without any sampleadded. Follow 6.6, 6.7, an
20、d 6.8.6.4 Disperse approximately 0.7 g of sample in 200 mL ofelectrolyte containing 5 drops of dispersing media, by mixingat high speed on the blender or its equivalent for 5 min.NOTE 5The proper dispersion conditions for a given mixer or blendershould be predetermined by obtaining a time-speed vers
21、us mediandiameter curve (see typical curve in Fig. A1.2) while ensuring thatgrinding does not occur. The position of the plateau will indicate theproper dispersion conditions for the sample. Experience has shown thatfull speed on the Waring Blender may cause size reduction. Slightly lessthan full sp
22、eed should be used. For some suspensions ultrasonic treatmentfrom 1 to 5 min is effective.6.5 With a pipet, transfer an appropriate aliquot of dispersedsample into the sample beaker containing electrolyte withdispersing media added in the ratio of 3 drops/200 mL ofelectrolyte. The aliquot size is de
23、pendent on the aperture sizeused. Wash down the pipet by rinsing with electrolyte severaltimes (see 6.9.3).NOTE 6The blender or mixer should be stirring just rapidly enough tomaintain a uniform particle suspension while withdrawing the sample. Thepipet should deliver all of the withdrawn slurry to e
24、nsure a representativetransfer of sample in the event of any size classification during thetransfer.6.6 Place the sample beaker in position on the sample stand.6.7 Adjust the speed of the stirrer to furnish sufficientagitation to maintain a uniform particle suspension, but belowair bubble generation
25、 speeds.6.8 Use the apparatus control software to set the measure-ment parameters. Make three measurements in which eachmeasurement counts and measures at least 5000 particles.Average the particle size distribution from the three measure-ments and report the statistical parameters from the averagedr
26、esults.6.9 Precautions:6.9.1 Before each analysis, using wash bottle and filteredwash water, wash all surfaces coming in contact with sample.6.9.2 Ensure that the calibration of the instrument is correctby checking the calibration factor at least once a week.6.9.3 The number of particles per unit vo
27、lume in the samplebeaker should not exceed that which will give a 5 % coinci-dence correction for the aperture tube being used (see Fig.A1.1).7. Presentation of Data7.1 Convert data to cumulative weight percent greater thanstated particle size according to instrument instruction manual.Coincidence i
28、s insignificant if total counts are limited to Fig.A1.1.NOTE 7For all electrical sensing zone counters the conversion isactually to volume percent. If all particles in the sample have the samedensity the volume percent and weight percent are interchangeable.7.2 Report size distribution graphs, table
29、s, and statisticssuch as: weight percent, count percent, volume percent, mean,median, mode, quartiles, and standard deviation.8. Precision and Bias8.1 Intralaboratory, Same OperatorExperience of severallaboratories indicates that the test method is capable of aprecision of 61 % (95 % confidence leve
30、l) for all size values.8.2 InterlaboratoryExperience of several laboratories in-dicates that the test method is capable of a precision of 63%(95 % confidence level) for all size values.8.3 BiasInstrument calibrations shall be performed usingNIST or NIST traceable uniform spheres with relative standa
31、rddeviation of 5 % or less.9. Keywords9.1 alumina; particle size; quartz; sensing zoneC690092ANNEX(Mandatory Information)A1. APERTURE CHART AND DISPERSION CURVEFigs.A1.1 andA1.2 are examples of the charts that should beemployed in conjunction with this test method.Nominal Aperture Size,mTotal Cumula
32、tive Count for 5 %Coincidence CorrectionApproximate Particle Size Rangein Equivalent Spherical DiameterSuggested CalibrationParticlesAManometer Volumem Diameter, m50 L 500 L 2000 L30 74 100AA0.6 to 12.0 1.5 to 6.050 15 950 159 500A1.0 to 20.0 2.5 to 10.070 5 810 58 100 232 400 1.4 to 28.0 3.5 to 14.
33、0100 2 000 20 000 80 000 2.0 to 40.0 5.0 to 20.0140 725 7 250 29 000 2.8 to 56.0 7.0 to 28.0200280AA2500A10 0003 6304.0 to 80.05.6 to 112.010.0 to 40.014.0 to 56.0AAperture size and manometer volume combination not recommended.FIG. A1.1 Typical Aperture ChartBlender Dispersion Time (Minutes)FIG. A1.
34、2 Example of a Sample Dispersion CurveC690093SUMMARY OF CHANGESCommittee C21 has identified the location of selected changes to this standard since the last issue (C 69003)that may impact the use of this standard.(1) Instruments are available from multiple suppliers and thusreference to particular i
35、nstruments in sections 4.1 and 4.8,along with footnotes 2 and 3 must be removed according toASTM policy. All other footnotes are renumbered accordingly.(2) Note 1 is revised to indicate aperture openings up to300m may be used, instead of 280m, since 300m are nowavailable with performance essentially
36、 the same as 280mtubes.(3) The word “Nominal” has been added to the heading for thefirst column in Fig. A1.1 since aperture tubes are available insizes slightly different from those given in the table.ASTM International takes no position respecting the validity of any patent rights asserted in conne
37、ction with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsi
38、ble technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful co
39、nsideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100
40、 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C690094
