1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58powders Part 5: Determination of particle size distributionThe European Standard EN 725-5:2007 has
2、the status of a British StandardICS 81.060.30Advanced technical ceramics Methods of test for ceramic BRITISH STANDARDBS EN 725-5:2007BS EN 725-5:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 September 2007 BSI 2007ISBN 978 0 580 5452
3、6 9Amendments issued since publicationAmd. No. Date CommentsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThi
4、s British Standard is the UK implementation of EN 725-5:2007, incorporating corrigendum August 2007. It supersedes BS EN 725-5:1996 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee RPI/13, Advanced technical ceramics.A list of organizations represented
5、 on this committee can be obtained on request to its secretary.EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 725-5January 2007ICS 81.060.30 Supersedes EN 725-5:1996 English VersionAdvanced technical ceramics - Methods of test for ceramicpowders - Part 5: Determination of particle size distributi
6、onCramiques techniques avances - Mthodes dessaispour poudre cramiques - Partie 5: Dtermination de ladistribution granulomtriqueHochleistungskeramik - Prfverfahren fr keramischePulver - Teil 5: Bestimmung der TeilchengrenverteilungThis European Standard was approved by CEN on 2 December 2006.CEN memb
7、ers are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application
8、 to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the s
9、ame status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Rom
10、ania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedwo
11、rldwide for CEN national Members.Ref. No. EN 725-5:2007: EIncorporating corrigendum August 2007 EN 725-5:2007 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Apparatus .4 4 Preparation of the suspension.4 5 Calibration 5 6 Procedure .5 7 Expression of results 6 8 Test report 6 Ann
12、ex A (informative) Suspending liquids and dispersing agents7 Annex B (informative) Certified reference materials11 Annex C (informative) Suspension and dispersion data.12 Annex D (informative) Example of particle size distribution.13 Annex E (informative) Presentation of particle size distribution d
13、ata .14 Bibliography 15 EN 725-5:2007 (E) 3 Foreword This document (EN 725-5:2007) has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publicatio
14、n of an identical text or by endorsement, at the latest by July 2007, and conflicting national standards shall be withdrawn at the latest by July 2007. This document supersedes EN 725-5:1996. EN 725 Advanced technical ceramics Methods of test for ceramic powders was prepared in Parts as follows: Par
15、t 1: Determination of impurities in alumina Part 2: Determination of impurities in barium titanate Part 3: Determination of the oxygen content of non-oxides by thermal extraction with a carrier gas Part 4: Determination of oxygen content in aluminium nitride by XRF analysis Part 5: Determination of
16、particle size distribution Part 6: Determination of the specific surface area withdrawn Part 7: Determination of the absolute density withdrawn Part 8: Determination of tapped bulk density Part 9: Determination of un-tapped bulk density Part 10: Determination of compaction properties Part 11: Determ
17、ination of densification on natural sintering Part 12: Chemical analysis of zirconia Parts 6 and 7 of the series were superseded in 2005 by EN ISO 18757 and EN ISO 18753 respectively. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries a
18、re bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Swe
19、den, Switzerland and United Kingdom. EN 725-5:2007 (E) 4 1 Scope This Part of EN 725 describes the preparation of suspensions and calibration of apparatus, prior to the measurement of particle size distribution of powders used for advanced technical ceramics. The preparation described is appropriate
20、 for measurements either by the sedimentation method or the laser light scattering method. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest editio
21、n of the referenced document (including any amendments) applies. EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025:2005) 3 Apparatus 3.1 Glass microscope slides and cover slips. 3.2 Optical microscope. 3.3 Beaker, 50 ml to 100 ml. 3.4 Ul
22、trasonicator. 3.5 Magnetic stirrer. 3.6 Particle size analyser. 4 Preparation of the suspension 4.1 Selection of liquid The dispersing liquid for the suspension shall not react with or dissolve the powder. For the sedimentation method of analysis, the density of the liquid shall be less than that of
23、 the powder by at least 0,5 g/cm. For the laser light scattering method of analysis, the liquid shall be optically transparent for the wavelength used. NOTE 1 This is generally 633 nm. The liquid shall have a refractive index which is substantially different from that of the sample. NOTE 2 Any speci
24、fic manufacturers instructions regarding the refractive index of the dispersing liquid should be taken into account. EN 725-5:2007 (E) 5 The liquid for the suspension shall be selected, together with any dispersing agent, from those given in Annex A. NOTE 3 Additional information is given in the bib
25、liographical references listed. The dispersion of powder in the liquid shall be checked by one of the methods given in 4.2. 4.2 Dispersion checking 4.2.1 Optical microscopic examination Place a drop of the prepared suspension on the glass slide (3.1) of a microscope (3.2) and carefully cover with a
26、cover slip (3.1). Observe the preparation under a suitable magnification, to determine if particles are completely separated and well dispersed, or if they are gathered together in chains or clusters. NOTE This method is not suitable for powders with particle diameters of less than 5 m. 4.2.2 Qualit
27、ative test by sedimentation Allow the suspension to stand. A correctly dispersed suspension settles less rapidly than a suspension which flocculates, and shows no clear border line between the liquid which becomes clear and the layer which is still turbid as sedimentation proceeds. The sediment obta
28、ined is compact and of a minimal volume. 4.2.3 Scanning electron microscope (S.E.M.) examination Check the correlation of the particle size distribution obtained with the mean size of the ultimate particles observed by S.E.M. If the suspension is not sufficiently dispersed, particles are partially a
29、ggregated and particle size distribution measurements thus give values much higher than the mean size of the ultimate particles observed. 4.2.4 Quantitative test by sedimentation Perform the quantitative tests, while allowing a variation of the various parameters liable to influence the dispersion q
30、uality. Choose the dispersion procedure which gives the smallest mean particle diameter. An examination of the shape of the distribution can give an indication of the presence of agglomerates. 5 Calibration Check the working order of the apparatus, by analysing standard powders regularly. NOTE Infor
31、mation on available standard reference powders is provided in Annex B. 6 Procedure 6.1 Determine the quantity of powder, the type and quantity of suspending liquid and the dispersing agent to be used. NOTE In principle, and within the limits imposed by the instrument, the sample mass to be dispersed
32、 has no influence on the results. However, it is preferable to use dilute suspensions. 6.2 For the sedimentation method, ensure that the volume concentration is less than or equal to 0,2 %. 6.3 For the laser Iight scattering method, for all determinations to be accurate, ensure that all particles pr
33、esent in the pencil rays are separate and diffract independently from each other. EN 725-5:2007 (E) 6 NOTE This condition should be fulfilled when each particle with a radius a is in the centre of a circle with a radius R = a, when there is no secant circle and when no particle casts a shadow on the
34、 others. 6.4 In a 50 ml to 100 ml beaker (3.3) prepare a first test sample. Mix the suspending liquid and the dispersing agent, add the powder while stirring the suspension, and disperse using the ultrasonicator (3.4) until free of agglomerates. Continue stirring with a magnetic stirrer (3.5) until
35、the start of the analysis. 6.5 Read the technical instructions of the instrument for general adjustments prior to the test and follow the manufacturers recommendations for using the instrument when performing the test. 6.6 Repeat the procedure on a second test sample and plot the particle size distr
36、ibution curves. If the curves are similar, it may be deduced that the dispersion is stable and that no mistake has been made during the test. If the curves are not similar, check the dispersion again (see 4.2). 7 Expression of results Record the suspension and dispersion conditions in a table simila
37、r to the example given in Annex C. Present the results either in graphic form as in Annex D, with the cumulative particle size distribution curve obtained automatically on the measurement sheet of the instrument, specifying test conditions in the appropriate part of the sheet, or as a table of resul
38、ts: a recommended layout example is given in Annex E. 8 Test report The test report shall be in accordance with the reporting provisions of EN ISO/IEC 17025 and shall include at least the following information: a) name and address of the testing establishment; b) date of the test; c) on each page, a
39、 unique report identification and page number; d) customer name and address; e) reference to this standard, i.e. determined in accordance with EN 725-5; f) authorising signature; g) any deviation from the method described, with appropriate validation, i.e. demonstrated to be acceptable to the partie
40、s involved; h) description of the test material (manufacturer, type, batch or code number, date of receipt) including any treatment before testing; i) suspension and dispersion conditions in the form of a table similar to the example given in Annex C; j) reference powder used to calibrate the instru
41、ment (see clause 5) and the results obtained on a given date; k) for the sedimentation method only, the apparent density of the powder, apparent density and viscosity of the suspending liquid, displacement rate of the cell, temperature of the suspension and the initial diameter; l) comments about th
42、e test or test results. EN 725-5:2007 (E) 7 Annex A (informative) Suspending liquids and dispersing agents The following alphabetical list in Table A.1 gives examples of suspending liquids and dispersing agents most commonly used for the main technical ceramic powders. Surface characteristics, and c
43、onsequently dispersion behaviour, depend on the powder type, but also on its manufacturing process. Therefore, the suspending liquid and dispersing agent may vary among powders of the same type. Among the dispersing agents listed in the third column of Table A.1, 9 are designated by a number (d.a No
44、. 1 to No 9). Their chemical composition is as follows: d.a. No 1 Dioctylsulfosuccinates; d.a. No 2 Trimethylcetyl ammonium bromide; d.a. No 3 Polyoxyethylene nonylphenol; d.a. No 4 Linear polyethoxy derivates; d.a. No 5 Sodium alkylnaphthalene sulfonate; d.a. No 6 Sorbitol monolaurate; d.a. No 7 Po
45、lyoxyethylene alkylphenol; d.a. No 8 Sodium alkylsulfonate; d.a. No 9 Polyoxyethylene octylphenol. EN 725-5:2007 (E) 8 Table A.1 - Suspending liquids and dispersing agents Material Suspending liquid Dispersing agent (0,5 g/l to 1,0 g/l, unless otherwise stated) Alumina see aluminium (oxide) Aluminiu
46、m (oxide) water Sodium pyrophosphate water Sodium pyrophosphatater Sodium tartrate water d.a. No 3 or No 4 or No 5 or No 9 water hydrochloric acid (pH 3) n-butanol n-butylamine linseed oil/xylene iso-octane d.a. No 6 Barium carbonate cyclohexanol, methanol Barium titanate water d.a. No 8 Boron (amor
47、phous) n-butanol n-butanol/ethanol (variousmixtures) Boron carbide water sodium pyrophosphate n-butanol/ethanol (variousmixtures) Boron nitride n-butanol n-butanol/ethanol (variousmixtures) Boron oxide water sodium pyrophosphate Chromium oxide water sodium phosphate cyclohexanol/isoamyl alcohol (9:1
48、) (v/v) (0,1 g/l to 0,3 g/l) Corundum see aluminium oxide sodium pyrophosphate Diamond (powder) olive oil gelatine in water (1 g/l to 2 g/l) sodium carbonate (pH 9) ethanol water trisodium orthophospate EN 725-5:2007 (E) 9 Table A.1 (continued) Material Suspending liquid Dispersing agent (0,5 g/l to
49、 1,0 g/l, unless otherwise stated) Graphite water water water water/ammonia ethanol n-butanol 0,5 g/l tannic acid 0,5 g/l d.a. No1 or No 8 5 g/l sodium linoleate (0,88 ml/l to 3,5 ml/l) Magnesium oxide (magnesia) water sodium polymetaphosphate Quartz see silica Rutile see titanium (dioxide) Silica water water water water water ethanol xylene water/ethanol (1:1) (v/v) sodium polymetaphosphate d.a. No 3 sodium pyrophosphate sodium pyrophosphate (1 g/l) + d.a. No 7 (0,2 g/l) trisodium orthophosphate Silicon carbide wat
