1、Designation: C 1070 01 (Reapproved 2007)Standard Test Method forDetermining Particle Size Distribution of Alumina or Quartzby Laser Light Scattering1This standard is issued under the fixed designation C 1070; the number immediately following the designation indicates the year oforiginal adoption or,
2、 in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of particlesize distribution of alumi
3、na or quartz using laser light scatter-ing instrumentation in the range from 0.1 to 500 m.1.2 The procedure described in this test method may beapplied to other nonplastic ceramic powders. It is at thediscretion of the user to determine the methods applicability.1.3 This test method applies to analy
4、sis using aqueousdispersions.1.4 This standard may involve hazardous materials, opera-tions and equipment. This standard does not purport to addressall of the safety concerns, if any, associated with its use. It isthe responsibility of the user of this standard to establishappropriate safety and hea
5、lth practices and determine theapplicability of regulatory limitations prior to use.1.5 Quartz has been classified by IARC as a Group Icarcinogen. For specific hazard information in handling thismaterial, see the suppliers Material Safety Data Sheet.2. Terminology2.1 Definitions of Terms Specific to
6、 This Standard:2.1.1 background,extraneous scattering of light by ele-ments other than the particles to be measured. This includesscattering by contamination in the measurement zone.2.1.2 Fraunhofer Diffraction,the optical theory that de-scribes the low-angle scattering of light by particles that ar
7、elarge compared to the wavelength of the incident light.2.1.3 Mie Scattering,the complex electromagnetic theorythat describes the scattering of light by spherical particles. It isusually applied to particles with diameters that are close to thewavelength of the incident light. The real and the imagi
8、naryindices of light diffraction are needed.22.1.4 multiple scattering,the rescattering of light by aparticle in the path of light scattered by another particle. Thismay occur in heavy concentrations of a particle dispersion.3. Summary of Test Method3.1 A sample dispersed in an aqueous medium is cir
9、culatedthrough the path of a light beam. As the particles pass throughthe light beam, the particles scatter light at angles inverselyproportional to their size and with an intensity directly propor-tional to their size. Detectors collect the scattered light whichis converted to electrical signals an
10、d analyzed in a micropro-cessor. The signal is converted to size distribution usingFraunhofer Diffraction or Mie Scattering, or a combination ofboth. The scattering information is then processed, assumingthe particles to be spherical, using algorithms or modelsproprietary to the particular instrumen
11、t manufacturer. Calcu-lated particle size distributions are presented as equivalentspherical diameters.4. Significance and Use4.1 It is important to recognize that the results obtained bythis method or any other method for particle size distributionutilizing different physical principles may disagre
12、e. The resultsare strongly influenced by the physical principles employed byeach method of particle size analysis. The results of anyparticle sizing method should be used only in a relative sense,and should not be regarded as absolute when comparing resultsobtained by other methods.4.2 Light scatter
13、ing theory that is used for determination ofparticle size has been available for many years. Severalmanufacturers of testing equipment have units based on theseprinciples.Although each type of testing equipment utilizes thesame basic principles for light scattering as a function ofparticle size, dif
14、ferent assumptions pertinent to applications ofthe theory and different models for converting light measure-ments to particle size may lead to different results for eachinstrument. Therefore, the use of this test method cannotguarantee directly comparable results from the various manu-facturers inst
15、ruments.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 May 1, 2007. Published June 2007. Originallyapproved in 1986. Last previous edition appr
16、oved in 2001 as C 1070-01.2Muly, E. C., Frock, H. W., “Industrial Particle Size Measurement Using LightScattering,” Optical Engineering, 196, pp. 86169 (1990).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.3 Manufacturers and purc
17、hasers of alumina and quartzwill find the method useful to determine particle size distribu-tions for materials specifications, manufacturing control, andresearch and development.5. Interferences5.1 Air bubbles entrained in the circulating fluid will scatterlight and then be reported as particles. C
18、irculating fluids do notrequire degassing, but should be bubble-free upon visualinspection.5.2 Reagglomeration or settling of particles during analysesmay cause erroneous results. Stable dispersions shall bemaintained throughout the analyses. To determine if stability ispresent, make multiple runs o
19、n the same sample and observe ifthe distribution stays the same throughout the analysis. If thedistribution gets coarser, then agglomeration is occurring. Ifthe distribution gets finer, there exists the possibility ofmaterial settling. Dispersion properties may be altered bychanging dispersants, use
20、 of ultrasonic energy prior to orduring analyses, and change of pumping speed during analyses.5.3 Insufficient sample loading may cause electrical noiseinterference and poor data repeatability. Excessive sampleloading may cause excessive light attenuation and multiplescattering, thereby resulting in
21、 erroneous particle size distribu-tions. The size distribution will have a tendency to be finer thanactually exists.6. Apparatus6.1 Particle Size Analyzer, based on Fraunhofer Diffractionor Mie Scattering or a combination of both light scatteringanalysis techniques. Care must be taken to ensure that
22、 theanalyzer system or subsystem is optimum for the size rangebeing tested.6.2 Liquid Handling System.7. Reagents7.1 Purity of ReagentsReagent grade of chemicals shallbe used in all tests. Unless otherwise indicated, it is intendedthat all reagents shall conform to the specifications of theCommittee
23、 on Analytical Reagents of the American ChemicalSociety, where such specifications are available. Other gradesmay be used, provided it is first ascertained that the reagent isof sufficiently high purity to permit its use without lesseningthe precision of the determination.7.2 Dispersion MediaDissolv
24、e 1.5 g of sodium metaphos-phate in 1 liter of distilled water and use this solution at anappropriate level so that the particles remain suspended in theaqueous system without creating bubbles. Other dispersantsmay be used for this purpose as well, such as SodiumPyrophosphate, Tween 80, Triton X100,
25、 Photoflow, or others.The optimum dispersant for the analysis is dependent on thematerial being analyzed and the amount of mixing and ultra-sound available for each particular particle size analyzersystem.8. Calibration and Standardization8.1 Performance of the instrument is defined by the spacingan
26、d position of the optical components. Refer to the manufac-turers instruction manual.8.2 Diagnostic materials should be available from the in-strument manufacturer to ensure consistent instrument func-tioning.8.3 Since no absolute standards are available for particlesize analysis, it is recommended
27、that one should develop asecondary reference material to assist in evaluating and opti-mizing instrument performance.9. Procedure9.1 Allow the instrument to warm up for the time recom-mended by the instrument manufacturer.9.2 If necessary, select applicable instrument range as indi-cated by the inst
28、rument manufacturers instructions and estab-lish correct optical alignment according to the instructions.9.3 If required and available, use the index of refractioncapability of the instrument. Many of the common compoundshave their index of refraction listed in the Handbook ofPhysical Chemistry. Man
29、y compounds can also be found listedin the instrument manufacturers instruction manual. The indexof refraction used should be relative to the aqueous media,which has a refractive index of 1.33. When entering the indexof refraction for the material being analyzed therefore, it isnecessary to divide t
30、he index of refraction of the compoundbeing analyzed by the index of refraction of water.9.4 Measure the background in the mode in which theanalysis will be performed. The dispersion media should beadded to the sampling chamber before the background mea-surement is performed. Be sure that the carrie
31、r fluid is flowingthrough the light path and the sample cell while measuring thebackground, and make sure that no bubbles are present.Background values shall not exceed the manufacturers speci-fications. If the background values exceed the manufacturersrecommendations, perform the necessary procedur
32、es as speci-fied by the manufacturer to bring the background values withinacceptable limits.9.5 Before adding the sample, be sure to use the appropriateamount of the dispersion media to the sampling chamber. Thenadd the test sample. Obtain a test sample using appropriatesampling techniques. Sample-s
33、plitting equipment such as chuteriflers and rotary rifflers are available commercially to assist inthese tasks. Refer to the instrument manufacturers recommen-dation to insure that the amount of the test sample is acceptableto obtain optimum light scattering conditions. A range ofsample size is acce
34、ptable depending upon the median particlesize and particle density.9.6 Select the appropriate run time for the sample. Thisprocedure is very specific to the application and is generallygauged by the run-to-run repeatability.9.7 Select the desired data output parameters according tothe requirements s
35、et forth by the instrument manufacturer.9.8 Determine proper dispersion conditions for the testsample. An example is described in Test Method C 690section6.4.NOTE 1Some instruments have built-in ultrasonic baths to aid indispersion. Others do not, and as a result, dispersions will have to be madeext
36、ernally using ultrasonic baths or probes. Also, food processors such asblenders may be used.C 1070 01 (2007)29.9 Perform the analysis according to the manufacturersinstruction.9.10 Upon completing the analysis, drain and rinse systemin preparation for the next analysis. Drain and rinse as manytimes
37、as necessary to obtain the background values as specifiedby the manufacturer.10. Precision and Bias10.1 PrecisionRepeatability study varied from 0.18 %above 7 m to 0.01 % at 1 m. Reproducibility study variedfrom 0.5 % above 7 m to 0.1 % below 1 m.10.2 BiasAs there are no generally accepted absolutes
38、tandards, bias cannot be determined.ASTM International takes no position respecting the validity of any patent rights asserted in connection 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 ris
39、kof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of thi
40、s standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration 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
41、your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 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).C 1070 01 (2007)3
