1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 22007-4:2012Plastics Determinationof thermal conductivity andthermal diffusivityPart 4: Laser flash method (ISO22007-4:2008)BS EN ISO 22007-4:2012 BRITISH STANDARDNatio
2、nal forewordThis British Standard is the UK implementation of EN ISO22007-4:2012.The UK participation in its preparation was entrusted to TechnicalCommittee PRI/21, Testing of plastics.A list of organizations represented on this committee can beobtained on request to its secretary.This publication d
3、oes not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580 75974 1ICS 83.080.01Compliance with a British Standard cannot confer immunity fromlegal
4、 obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 29 February 2012.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 22007-4 January 2012 ICS 83.080.01 English Version Plas
5、tics - Determination of thermal conductivity and thermal diffusivity - Part 4: Laser flash method (ISO 22007-4:2008) Plastiques - Dtermination de la conductivit thermique et de la diffusivit thermique - Partie 4: Mthode flash laser (ISO 22007-4:2008) Kunststoffe - Bestimmung der Wrmeleitfhigkeit und
6、 der Temperaturleitfhigkeit - Teil 4: Laserblitzverfahren (ISO 22007-4:2008) This European Standard was approved by CEN on 24 December 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a nati
7、onal standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A ver
8、sion in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus,
9、Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATIO
10、N COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 22007-4:2012: EBS EN ISO 22007-4:2012EN ISO 22007-4:2012
11、(E) 3 Foreword The text of ISO 22007-4:2008 has been prepared by Technical Committee ISO/TC 61 “Plastics” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 22007-4:2012 by Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN. T
12、his European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by July 2012, and conflicting national standards shall be withdrawn at the latest by July 2012. Attention is drawn to the possibility that some of the e
13、lements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this
14、 European Standard: Austria, Belgium, Bulgaria, Croatia, 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, Sweden, Switzerland,
15、 Turkey and the United Kingdom. Endorsement notice The text of ISO 22007-4:2008 has been approved by CEN as a EN ISO 22007-4:2012 without any modification. BS EN ISO 22007-4:2012ISO 22007-4:2008(E) ISO 2008 All rights reserved iiiContents PageForeword iv1Scope12Normative references13Terms and defini
16、tions .14Principle25Apparatus.25.1General25.2 Furnace or climatic chamber25.3Flash source.45.4 Transient detectors45.5 Thickness measurement device.56Test specimen56.1 Shape and dimension of the specimen.56.2 Preparation and conditioning of test specimen.56.3Coating the specimen .57Calibration and v
17、erification 67.1 Calibration of apparatus .67.2 Verification of apparatus.68Procedure.69Data analysis710 Uncertainty.911 Test report9Annex A (informative) Correction for finite pulse duration.10Annex B (informative) Alternative methods of calculating thermal diffusivity.11Bibliography12BS EN ISO 220
18、07-4:2012ISO 22007-4:2008(E)iv ISO 2008 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide f ederation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical commit
19、tees. Each member bodyinterested in a subject for which a technical committee has beenestablished has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closelywith the Inter
20、national Electrotechnical Com mission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International St
21、andardsadopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subj
22、ect of patent rights. ISO shall not be held responsible for identifying an y or all such patent rights. ISO 22007-4 was prepared by Technical Committee ISO/TC61, Plastics , Subcommittee SC 5, Physical-chemical properties. ISO 22007 consists of the following parts, under the general title Plastics De
23、termination of thermalconductivity and thermal diffusivity: Part 1: General principles Part 2: Transient plane heat source (hot disc) method Part 3: Temperature waveanalysis method Part 4: Laser flash method BS EN ISO 22007-4:2012INTERNATIONAL STANDA RD ISO 22007-4:2008(E) ISO 2008 All rights reserv
24、ed 1Plastics Determination of thermal conductivity and thermal diffusivity Part 4: Laser flash method 1 Scope 1.1 This part of ISO 22007 specifies a method for the determination of the thermal diffusivityof a thin soliddisc of plastics in the thickness direction bythe laser flas h method. This metho
25、d is based upon themeasurement of the temperature rise at the rear face of the thin-disc specimen produced by a short energypulseon the front face. 1.2 The method can be used for homogeneous solid plastics as well as composites having an isotropic ororthotropic structure. In general, it covers mater
26、ials having a thermal diffusivity, , in the range1 10 7 m2 s 1 m 1 0,27: F ( m 1 ) = 0,085 48 0,314(0,548 6 m 1 ) + 0,500(0,548 6 m 1 ) 2,63 (5) For m 1 0,44: F ( m 1 ) = 0,081 9 + 0,305m 1 6) NOTE 2Values of m 1 less than 0,27 should not be obtained as they do not have any physical significance. Th
27、is calculation method can be used if the following conditions are satisf ied: the duration of the laser pulse is short compared with the time characteristic for thermal diffusion (i.e. pulse width 1 % of t 1/2 ) or, if not, a correction is applied to the time scale in accordance withAnnex A; the fro
28、nt face of the specimen is uniformlyheated by the laser pulse; the specimen is homogeneous; the specimen is opaque to the laser radiation at the wavelength used. NOTE 3The potential effect of non-uniformity of the pulse on the calculated thermal diffusivity can usually be assumedto be negligible due
29、 to the use of an IR detector to detect the transient temperature rise of the specimen rear face. However, if needed, the laser beam could be made more uniform by using beam-homogenizing optics. NOTE 4The assumption of opacity of the specimen is implicitly satisfied by the deposit of an appropriate
30、coating on itstwo faces. BS EN ISO 22007-4:2012ISO 22007-4:2008(E) ISO 2008 All rights reserved 910 UncertaintyThe relative expanded uncertainty (confidence level of 95 %) of the th ermal-diffusivity determination by thelaser flash method with the partial timemoments method is estimated to be from 3
31、 % to 5 % 6 betweenambient temperature and 400 C (depending on the materialand the temperature). It has been calculated inaccordance with the ISO/IEC Guide 98-3. On the basis of the results of five successive measurements performed under the same conditions, the repeatability of the method is better
32、 than 1 %. 11 Test reportThe test report shall include the following information:a) a reference to this part of ISO 22007; b) the date of the test; c) all details necessary for complete identification of the sample tested (type, batch number, etc. ), includingits thermal history;d) the shape and dim
33、ensions (diameter and thicknessesat room temperature and at each test temperature, giving the method of calculation of the thicknesses at the test temperatures) of the specimens and thenumber of specimens tested; e) details of sample and specimen preparation; f) whether a coating was used and, if so
34、, the coating material and coating procedure and the thickness ofthe coating); g) the wavelength and duration of the laser pulse; h) the type of detector used formeasuring the transient temperature ris e of the specimen rear face; i) the type of furnace used and its temperature range (or a statement
35、 to the effect that a climatic chamberwas used); j) the measurement conditions, such as the test temperature(s), in degrees Ce lsius, and the furnace atmosphere; k) the method(s) used to calculate the thermal diffusivity and estimate cor rections (e.g. due to heat losses and the finite pulse duratio
36、n); l) the thermal-diffusivityvalue(s) obtained, in square metres per second; m) anyadditional information or details of operations not specified in this part of ISO 22007, which may beimportant for assessment of the results.BS EN ISO 22007-4:2012ISO 22007-4:2008(E)10 ISO 2008 All rights reservedAnn
37、ex A(informative) Correction for finite pulse duration All the methods used to calculate thermal diffusivityassume that the laser pulse is similar to a Dirac function.However,if the duration of the pulse cannot be neglected (see Clause 9), the effect of the finite pulse timeshould be corrected for.F
38、or the methods of calculation based on the use of the half-rise time, t 1/2 , a first approach consists incalculating the thermal diffusivity, assuming a Dirac function pulse, and applying a correction to the valueobtained. By specifying the shapes of pulses, several authors 7,8,9 have proposed anal
39、ytical relationshipsto estimate this correction.A more general method consists in shifting the time origin to the centroid, t g , of the laser pulse and calculating the thermal diffusivity considering the pulse as a Dirac function. In this case, the waveform of the laser pulse is measured by a detec
40、tor having a response faster than 10 s and the position of the centroid is calculateddirectly from the observed waveform. This method, proposed initially by Azumi and Takahashi 10 for adiabatic experiments, has been extended to non-adiabatic ones by Degiovanni 11. BS EN ISO 22007-4:2012ISO 22007-4:2
41、008(E) ISO 2008 All rights reserved 11Annex B(informative) Alternative methods of calculating thermal diffusivityAll methods ofcalulating thermal diffusivity are based on the mathematical solution of the heat conductionequationwith appropriate initial and boundary conditions. The original me thod pr
42、oposed by Parker et al. 12 isbased on an analytical model corresponding to an adiabatic experiment, on the basis of which the thermaldiffusivity is calculated from the half-rise time, t 1/2 . In the case of an adiabatic experiment, the thermal diffusivity is calculated simply from the thickness, d ,
43、 and the half-rise time, t 1/2 , as follows: 21/20,13879 dt = (B.1) The use of this method, which neglects heat losses, can generate significant systematic errors in thermal-diffusivity determinations. It is not a suitable method for polymers because of their low thermal diffusivity and the test can
44、not really be considered adiabatic. Somemethods are based on an improvement of Parkersmethod, introducing correction factors in thecalculation of the thermal diffusivity to take into account the unavoidable heat losses. They use one or severalcharacteristicpoints on the experimental curve. Among the
45、m, Cape and Lehmansmethod 13, Cowansmethod 14 and Clark and Taylors method 15 are the most commonly used. With the advances in modern data acquisition, methods based on the analysis of a part (i.e. the partial timemoments method of Degiovanni and Laurent 5 ) or the whole of the temperature response
46、(i.e. the techniqueproposed by Gembarovic et al. 16 using a least-squares method) are increasinglyutilized. These calculation methods are generally based on minimizing the difference between the measured values and the theoreticalvalues obtained from a mathematical model. They differ either bythe an
47、alytical model used or by the wayin which they compare the measured experimental temperature rise versus time recordings with the analyticalcurve.BS EN ISO 22007-4:2012ISO 22007-4:2008(E)12 ISO 2008 All rights reservedBibliography1 ISO 18755, Fine ceramics (advanced ceramics, advanced technical cera
48、mics) Determination ofthermal diffusivity of monolithic ceramics by laser flash method2 S ALMON , D.,BAXENDALE, S., G ROBOTH, G.,HAY, B., H AMMERSCHMIDT , U., B RANDT , R., S INNEMA, S. andB AILLIS ,D.: Thecertification of thermal conductivity and diffusivityproperties of Pyroceram 9606 as areferenc
49、e material up to 1 000 C, HTCRM,Certification Report (2003)3 http:/www.irmm.jrc.be4 A KOSHIMA ,M. and B ABA, T.: Thermal Diffusivity Measurements of Candidate Reference Materials bythe Laser Flash Method, Int. J. of Thermophysics, 26 (1), pp. 151-163 (2005)5 D EGIOVANNI, A. and L AURENT, M.: Une nouvelle technique didentification de la diffusivit thermique parmthode flash, Rev. Phys. Appl., 21, pp. 229-237 (1986)6 H AY, B., F ILTZ, J.-R., H A
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