BS ISO 19618-2017 Fine ceramics (advanced ceramics advanced technical ceramics) Measurement method for normal spectral emissivity using blackbody reference with an FTIR spectromete.pdf

1、BS ISO 19618:2017Fine ceramics (advancedceramics, advanced technicalceramics) Measurementmethod for normal spectralemissivity using blackbodyreference with an FTIRspectrometerBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 19618:2017 BRITISH STANDARDNational f

2、orewordThis British Standard is the UK implementation of ISO 19618:2017.The UK participation in its preparation was entrusted to Technical Committee RPI/13, Advanced technical ceramics.A list of organizations represented on this committee can be obtained on request to its secretary.This publication

3、does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017.Published by BSI Standards Limited 2017ISBN 978 0 580 87937 1 ICS 81.060.30 Compliance with a British Standard cannot confer immunity from

4、 legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 February 2017.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 19618:2017 ISO 2017Fine ceramics (advanced ceramics, advanced technical ceram

5、ics) Measurement method for normal spectral emissivity using blackbody reference with an FTIR spectrometerCramiques techniques Mthode de mesure de lmissivit spectrale normale utilisant un corps noir de rfrence avec un spectromtre FTIRINTERNATIONAL STANDARDISO19618First edition2017-02Reference number

6、ISO 19618:2017(E)BS ISO 19618:2017ISO 19618:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electroni

7、c or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Ge

8、neva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 19618:2017ISO 19618:2017(E)Foreword iv1 Scope . 12 Normative references 13 Terms, definitions and symbols 14 Principle 25 Apparatus . 25.1 Measurement system. 25.2 Fourier transform infrared spectrometer (FTI

9、R) . 25.3 Specimen heating device 25.4 Blackbody furnace 45.5 Temperature measuring devices and thermometer . 45.6 Mirror 46 Test specimens 47 Measurement preparation . 67.1 Position of a blackbody furnace and a specimen . 67.2 Wavelength calibration 67.3 Verification of linearity 67.4 Verification

10、of stability . 67.5 Validation of measurement system . 68 Test condition 79 Test procedure 79.1 Background infrared radiance spectrum measurement . 79.2 Specimen installation 79.3 Infrared radiance spectrum measurement . 710 Calculations 710.1 Normal spectral emissivity . 710.2 Normal quasi-total em

11、issivity 811 Test report . 9Annex A (informative) Calculation of theoretical infrared radiance spectrum L(,T) using Plancks blackbody radiation function .10Annex B (informative) Christiansen effect 11Annex C (informative) Validity of normal quasi-total emissivity .12Bibliography .13 ISO 2017 All rig

12、hts reserved iiiContents PageBS ISO 19618:2017ISO 19618:2017(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical comm

13、ittees. Each member body interested in a subject for which a technical committee has been established 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 closely with the

14、International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the

15、 different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.

16、ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www .iso .org/ patents).Any trade name used in this

17、document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in

18、the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 206, Fine ceramics.iv ISO 2017 All rights reservedBS ISO 19618:2017INTERNATIONAL STANDARD ISO 19618:2017(E)Fine ceramics (advanced ceramics, advanc

19、ed technical ceramics) Measurement method for normal spectral emissivity using blackbody reference with an FTIR spectrometer1 ScopeThis document specifies a method used for the determination of normal spectral emissivity and normal quasi-total emissivity of fine ceramics using blackbody reference wi

20、th a Fourier transform infrared spectrometer (FTIR) at elevated temperatures. This method is applicable to fine ceramics, ceramic matrix composites, and continuous fibre-reinforced ceramic matrix composites which are opaque and highly non-reflective at wavelengths between 1,67 m and 25 m. The applic

21、able temperature range is approximately 350 K to 1 100 K.2 Normative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references,

22、the latest edition of the referenced document (including any amendments) applies.IEC 60584-2, Thermocouples Part 2: TolerancesIEC 60751, Industrial platinum resistance thermometers and platinum temperature sensors3 Terms, definitions and symbolsFor the purposes of this document, the following terms

23、and definitions apply.ISO and IEC maintain terminological databases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp3.1emissivityratio of the radiant emitt

24、ance of a substance (specimen) to the radiant emittance of a blackbody (3.2) at the same temperature3.2blackbodyideal thermal radiator that absorbs all incident radiation completely, whatever the wavelength, direction of incidence or polarization3.3spectral emissivitys(, T)emissivity (3.1) of a spec

25、imen at a defined wavelength and temperature T ISO 2017 All rights reserved 1BS ISO 19618:2017ISO 19618:2017(E)3.4normal spectral emissivityns(, T)emissivity (3.1) perpendicular to the specimen at a defined wavelength and temperature T3.5normal total emissivityn(T)ratio of the normal component of th

26、e total emissive power of a specimen surface to the normal component of the total emissive power of a blackbody at the same temperature T3.6normal quasi-total emissivityn(1, 2, T)normal emissivity between 1and 2at temperature TNote 1 to entry: Calculated as the ratio of the normal component of the e

27、missive intensity of a specimen between 1and 2to the normal component of the emissive intensity of a blackbody between 1and 2at the same temperature T.4 PrincipleThe infrared radiance spectrum data from a specimen surface and from a blackbody furnace are measured using an FTIR spectrometer. The norm

28、al spectrum emissivity of a specimen is determined by direct comparison to a blackbody reference data at the same temperature.Integrating the infrared radiance spectrum data in the specified wavelength range numerically, normal quasi-total emissivity is calculated.5 Apparatus5.1 Measurement systemTh

29、e measurement system consists of a Fourier transform infrared spectrometer (FTIR), specimen heating device, blackbody furnace, and temperature measuring devices as shown in Figure 1.5.2 Fourier transform infrared spectrometer (FTIR)Infrared radiation from a specimen or a blackbody furnace is let int

30、o a Mickelson interferometer of an FTIR through an external optical path. Thereby, an interferogram of infrared radiation is obtained. The infrared radiance spectrum is obtained numerically by Fourier transformation processing from the interferogram.The optical system including a Mickelson interfero

31、meter of an FTIR shall be filled with dry N2or dry air of which the dew point is lower than 220 K to reduce the effect of H2O and CO2in air. Vacuum may be used.The measurement spot area at the sample position and at the blackbody furnace positions shall be measured preliminarily.5.3 Specimen heating

32、 deviceA specimen shall be heated using a heating device such as electrical resistance heating elements, heat-pipes, heat-transfer media, etc. The specimen surface temperature shall be well controlled to within 3 K.An example of a specimen heating device is depicted in Figures 2 and 3.2 ISO 2017 All

33、 rights reservedBS ISO 19618:2017ISO 19618:2017(E)Key1 blackbody furnace2 specimen heating device3 specimen4 FTIR spectrometer5 switchable mirror6 external optical pathFigure 1 Measurement systemKey1 specimen2 hot plate (block)3 resistance heater elements4 thermal insulator5 cavityFigure 2 Example o

34、f a specimen heating device: electrical resistance furnace ISO 2017 All rights reserved 3BS ISO 19618:2017ISO 19618:2017(E)Key1 specimen2 device body3 channel for heat transfer media4 inlet5 outletFigure 3 Example of a specimen heating device: heat transfer media5.4 Blackbody furnaceTotal emissivity

35、 of a blackbody furnace shall be higher than 0,95 and shall be internationally traceable. The aperture size shall be greater than three times the measurement spot area of an FTIR.5.5 Temperature measuring devices and thermometerAll temperature measuring devices (temperature sensor) shall be internat

36、ionally traceable.The temperature sensor used for a test specimen shall be thermocouple in accordance with IEC 60584-2, or resistance temperature detector in accordance with IEC 60751.The sensor diameter shall be as small as possible to prevent heat transfer through the sensor wires.5.6 MirrorA mirr

37、or with reflection index of more than 0,95 is used to measure background infrared radiance spectrum at room temperature. A gold-coated mirror should be used.6 Test specimensA material shall be opaque and highly non-reflective at wavelengths between 1,67 m and 25 m. The specimen shall have plain plat

38、e geometry. The specimen area shall be more than three times the measurement spot area of a spectrometer at a measurement position. Typical dimensions are 2 mm to 6 mm thick, and 10 mm to 50 mm in diameter or in square. The back side of a specimen shall be flat and smooth to be in close contact with

39、 a specimen heating device. The machining parameters for specimen surfaces should be documented.4 ISO 2017 All rights reservedBS ISO 19618:2017ISO 19618:2017(E)A temperature sensor such as a thermocouple shall be contacted firmly to a specimen. The two methods shown in Figure 4 should be used. A tem

40、perature sensor is bonded on a specimen surface using welding or adhesion. The temperature sensor and adhesive shall not appear inside of the measurement spot area. A few centimetres of the temperature sensor should be bonded on the surface to prevent thermal conduction through the sensor wires. A t

41、emperature sensor is embedded into a small hole machined from a specimen side surface. The embedded length should be more than 5 mm to 20 mm to prevent thermal conduction through the sensor wires.a) Bonded on a specimen using adhesiveb) Embedded in a specimen from side surfaceKey1 measurement spot a

42、rea2 temperature sensor3 adhesiveFigure 4 Temperature sensor attachment methods ISO 2017 All rights reserved 5BS ISO 19618:2017ISO 19618:2017(E)7 Measurement preparation7.1 Position of a blackbody furnace and a specimenA specimen and a blackbody furnace shall be placed at the optically equivalent po

43、sition from an FTIR spectrometer.A measurement spot area shall be at the centre of an aperture of the blackbody furnace and at the centre of a specimen.7.2 Wavelength calibrationThe spectral resolution shall be better than 16 cm1. The number of data acquisitions and integrations shall be greater tha

44、n 100. Arbitrary data smoothing methods are applicable.Wavelength (wavenumber) calibration of an FTIR shall be conducted using a polystyrene calibration film. The test results shall be documented.7.3 Verification of linearityThe linearity of infrared radiance spectrum data shall be verified before m

45、easurement. The following two methods should be used.a) The infrared radiance spectrum of a blackbody furnace, Ib(,T), is measured at three different temperatures (T1 T2 T3). The ratios of the measured spectrum, Ib(,T1)/Ib(,T3) and Ib(,T2)/Ib(,T3), are calculated. The results are shown in a graph as

46、 a function of wavelength. The theoretical infrared radiance spectrum at each temperature, L(,T), is calculated using Plancks blackbody radiation function (see Annex A). The ratios L(,T1)/L(,T3) and L(,T2)/L(,T3) are calculated. The theoretical curves are superimposed on the graph. Comparing the mea

47、sured data and the theoretical curves, the linearity of an FTIR system shall be verified. The test results shall be documented.b) The infrared radiance spectrum of a blackbody furnace is measured at the test temperature. A 50 % infrared neutral density filter is inserted in the external optical syst

48、em; then the infrared radiance spectrum of a blackbody furnace is measured. Furthermore, cutting off an external optical system, the infrared radiance spectrum is measured. By comparing the measured data (100 %, 50 %, and 0 %), the linearity of an FTIR system shall be verified. Test results shall be

49、 documented.7.4 Verification of stabilityThe stability of measurement systems shall be verified by the measurement of infrared radiance spectrum from a blackbody furnace. The infrared radiance spectrum from a blackbody is measured twice within 10 min. The ratio of these two results shall be within (100 1) %. The test results shall be documented.7.5 Validation of measurement systemThe measurement system shall be validated by comparing the measured data and literature data of some