1、BRITISH STANDARD BS EN 1892:2005 Advanced technical ceramics Mechanical properties of ceramic composites at high temperature under inert atmosphere Determination of tensile properties The European Standard EN 1892:2005 has the status of a British Standard ICS 81.060.30 Licensed Copy: Wang Bin, na, F
2、ri Aug 05 04:13:57 BST 2005, Uncontrolled Copy, (c) BSIBS EN 1892:2005 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 6 May 2005 BSI 6 May 2005 ISBN 0 580 45996 9 National foreword This British Standard is the official English language versi
3、on of EN 1892:2005. It supersedes DD ENV 1892:1996 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee RPI/13, Advanced technical ceramics, which has the responsibility to: A list of organizations represented on this committee can be obtained on request t
4、o its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electr
5、onic Catalogue or of British Standards Online. This 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 does not of itself confer immunity from legal obligations. aid enquirers to un
6、derstand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document compr
7、ises a front cover, an inside front cover, the EN title page, pages 2 to 21 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments Licensed Copy: Wang Bin, na, Fri Aug 05 04:13:57 B
8、ST 2005, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1892 April 2005 ICS 81.060.30 Supersedes ENV 1892:1996 English version Advanced technical ceramics - Mechanical properties of ceramic composites at high temperature under inert atmosphere - Determination of tens
9、ile properties Cramiques techniques avances - Proprits mcaniques des cramiques composites haute temprature sous atmosphre neutre - Dtermination des caractristiques en traction Hochleistungskeramik - Mechanische Eigenschaften von keramischen Verbundwerkstoffen bei hoher Temperatur in inerter Atmosphr
10、e - Bestimmung der Eigenschaften unter Zug This European Standard was approved by CEN on 15 March 2005. 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 national standard without any alteration.
11、 Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
12、under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
13、 Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Sta
14、ssart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1892:2005: E Licensed Copy: Wang Bin, na, Fri Aug 05 04:13:57 BST 2005, Uncontrolled Copy, (c) BSIEN 1892:2005 (E) 2 Contents Page Foreword3 1 Scope 4 2
15、 Normative references 4 3 Terms, definitions and symbols.4 4 Principle6 5 Apparatus .6 6 Test specimens8 7 Test specimen preparation.15 8 Test procedures.15 9 Calculation of results 17 10 Test report 19 Annex A (informative) Test specimen for use with optical extensometry.20 Bibliography 21 Licensed
16、 Copy: Wang Bin, na, Fri Aug 05 04:13:57 BST 2005, Uncontrolled Copy, (c) BSIEN 1892:2005 (E) 3 Foreword This document (EN 1892:2005) 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
17、status of a national standard, either by publication of an identical text or by endorsement, at the latest by October 2005, and conflicting national standards shall be withdrawn at the latest by October 2005. This document supersedes ENV 1892:1996. According to the CEN/CENELEC Internal Regulations,
18、the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Po
19、land, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: Wang Bin, na, Fri Aug 05 04:13:57 BST 2005, Uncontrolled Copy, (c) BSIEN 1892:2005 (E) 4 1 Scope This document specifies the conditions for determination of tensile properties of ceramic matrix composit
20、e materials with continuous fibre reinforcement for temperatures up to 2 000 C under vacuum or a gas atmosphere which is inert to the material under test. NOTE The use of these environments is aimed at avoiding changes of the material to be tested due to chemical reaction with its environment during
21、 the test. This document applies to all ceramic matrix composites with a continuous fibre reinforcement, unidirectional (1D), bidirectional (2D), and tridirectional (xD, with 2 x 3), loaded along one principal axis of reinforcement. 2 Normative references The following referenced documents are indis
22、pensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 10002-4; Metallic materials - Tensile test - Part 4: Verification of extensometers used in
23、 uniaxial testing EN 60584-1, Thermocouples; Part 1: Reference tables (IEC 60584-1:1995) EN 60584-2, Thermocouples; Part 2: Tolerances (IEC 60584-2:1982 + A1:1989) EN ISO 7500-1, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verifica
24、tion and calibration of the force-measuring system. (ISO 7500-1:2004) ISO 3611, Micrometer callipers for external measurement 3 Terms, definitions and symbols For the purposes of this document, the following terms, definitions and symbols apply. 3.1 test temperature, T temperature of the test piece
25、at the centre of the gauge length 3.2 calibrated length, l part of the test specimen which has uniform and minimum cross-section area 3.3 gauge length, L oinitial distance between reference points on the test specimen in the calibrated length 3.4 controlled temperature zone part of the calibrated le
26、ngth including the gauge length where the temperature is controlled to within 50 C of the test temperature 3.5 initial cross-section area, S oinitial cross-section area of the test specimen within the calibrated length, at test temperature Licensed Copy: Wang Bin, na, Fri Aug 05 04:13:57 BST 2005, U
27、ncontrolled Copy, (c) BSIEN 1892:2005 (E) 5 3.6 longitudinal deformation, A increase in the gauge length between reference points under a tensile force. 3.7 longitudinal deformation under maximum tensile force, A mincrease in the gauge length between reference points under maximum tensile force 3.8
28、tensile strain, relative change in the gauge length defined as the ratio A/L o3.9 tensile strain under maximum tensile force, mrelative change in the gauge length defined as the ratio A/L ocorresponding to the maximum force 3.10 tensile stress, tensile force supported by the test specimen at any tim
29、e in the test divided by the initial cross-section area 3.11 maximum tensile force, F mhighest recorded tensile force in a tensile test on the test specimen when tested to failure 3.12 tensile strength, mratio of the maximum tensile force to the initial cross-section area 3.13 proportionality ratio
30、or pseudo-elastic modulus EP slope of the linear section of the stress-strain curve, if any. NOTE Examination of the stress-strain curves for ceramic matrix composites allows definition of the following cases: a) material with a linear section in the stress-strain curve; For ceramic matrix composite
31、s that have a mechanical behaviour characterised by a linear section, the proportionality ratio is defined as: () () () 1 2 1 2 2 1 , = EP (1) where ( 1, 1) and ( 2, 2) lie near the lower and the upper limits of the linear section of the stress-strain curve. The proportionality ratio or pseudo-elast
32、ic modulus is termed the elastic modulus, E, in the single case where the linearity starts near the origin. b) material with no-linear section in the stress-strain curve. In this case only stress-strain couples can be fixed. Licensed Copy: Wang Bin, na, Fri Aug 05 04:13:57 BST 2005, Uncontrolled Cop
33、y, (c) BSIEN 1892:2005 (E) 6 4 Principle A test specimen of specified dimensions is heated to the test temperature, and loaded in tension. The test is performed at constant crosshead displacement rate, or constant deformation rate (or constant loading rate). Force and longitudinal deformation are me
34、asured and recorded simultaneously. NOTE 1 The test duration is limited to reduce creep effects. NOTE 2 When constant loading rate is used in the non-linear region of the tensile curve, only the tensile strength can be obtained from the test. In this region constant crosshead displacement rate or co
35、nstant deformation rate is recommended to obtain the complete curve. 5 Apparatus 5.1 Test machine The test machine shall be equipped with a system for measuring the force applied to the test specimen conforming to grade 1 or better according to EN ISO 7500-1. This shall apply during actual test cond
36、itions of, e.g. gas pressure and temperature. 5.2 Load train The load train configuration shall ensure that the load indicated by the load cell and the load experienced by the test specimen are the same. The load train performance, including the alignment system and the force transmitting system, sh
37、all not change because of heating. The attachment fixtures shall align the test specimen axis with the applied force direction. NOTE 1 The alignment should be verified and documented, according to, for example the procedure described in the HTMTC code of practice 1. The grip design shall prevent the
38、 test specimen from slipping. There are two types of gripping systems. hot grips where the grips are in the hot zone of the furnace; cooled grips where the grips are outside the hot zone. NOTE 2 The choice of gripping system will depend on material, on test specimen design and on alignment requireme
39、nts. NOTE 3 The hot grip technique is limited in temperature because of the nature and strength of the materials that can be used for grips. NOTE 4 In the cooled grip technique, a temperature gradient exists between the centre which is at the prescribed temperature and the ends which are at the same
40、 temperature as the grips. 5.3 Test chamber The test chamber shall be gas tight and shall allow proper control of the test specimen environment in the vicinity of the test specimen during the test. Licensed Copy: Wang Bin, na, Fri Aug 05 04:13:57 BST 2005, Uncontrolled Copy, (c) BSIEN 1892:2005 (E)
41、7 The installation shall be such that the variation of the load due to the variation of pressure is less than 1 % of the scale of the load cell being used. Where a gas atmosphere is used, the gas atmosphere shall be chosen depending on the material to be tested and on test temperature. The level of
42、pressure shall be chosen depending: on the material to be tested, on temperature, on the type of gas, and on the type of extensometry. Where a vacuum chamber is used, the level of vacuum shall not induce chemical and/or physical instabilities of the test specimen material, and of extensometer rods,
43、when applicable. 5.4 Set-up for heating The set-up for heating shall be constructed in such a way that the temperature gradient within the gauge length is less than 20 C at test temperature. 5.5 Extensometer The extensometer shall be capable of continuously recording the longitudinal deformation at
44、test temperature and conforming to class 1 or better, in accordance with EN 10002-4. NOTE 1 The use of an extensometer with the greatest gauge length is recommended. The linearity tolerances shall be lower than 0,05 % of the extensometer range used. Two commonly used types of extensometer are the me
45、chanical extensometer and the electro-optical extensometer. Using a mechanical extensometer, the gauge length is the longitudinal distance between the two locations where the extensometer rods contact the test specimen. The rods may be exposed to temperatures higher than the test specimen temperatur
46、e. Temperature and/or environment induced structural changes in the rod material shall not affect the accuracy of deformation measurement. The material used for the rods shall be compatible with the test specimen material. NOTE 2 Care should be taken to correct for changes in calibration of the exte
47、nsometer that may occur as a result of operating under conditions different from calibration. NOTE 3 Rod pressure onto the test specimen should be the minimum necessary to prevent slipping of the extensometer rods. In the case of an electro-optical extensometer, electro-optical measurements in trans
48、mission require reference marks on the test specimen. For this purpose rods or flags shall be attached to the surface perpendicularly to its axis. The gauge length shall be the distance between the two reference marks. The material used for marks (and adhesive if used) shall be compatible with the t
49、est specimen material and the test temperature and shall not modify the stress field in the specimen. NOTE 4 The use of integral flags as parts of the test specimen geometry is not recommended because of stress concentration induced by such features. 5.6 Temperature measurement devices For temperature measurement, either thermocouples conforming to EN 60584-1 and EN 60584-2 shall be used, or, where thermocouples not conf
