1、BRITISH STANDARDBS EN 12290:2005Advanced technical ceramics Mechanical properties of ceramic composites at high temperature under inert atmosphere Determination of compression propertiesThe European Standard EN 12290:2005 has the status of a British StandardICS 81.060.30g49g50g3g38g50g51g60g44g49g42
2、g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Licensed Copy: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontrolled Copy, (c) BSIBS EN 12290:2005This British Standard
3、was published under the authority of the Standards Policy and Strategy Committee on 31 January 2007 BSI 2007ISBN 978 0 580 49959 3National forewordThis British Standard was published by BSI. It is the UK implementation of EN 12290:2005. It supersedes DD ENV 12290:1996 which is withdrawn.The UK parti
4、cipation in its preparation was entrusted to Technical Committee RPI/13, Advanced technical ceramics.A list of organizations represented on RPI/13 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsibl
5、e for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments issued since publicationAmd. No. Date CommentsLicensed Copy: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEUROPEAN STANDARD NORME EUROPENNE EUROPIS
6、CHE NORM EN 12290 June 2005 ICS 81.060.30 Supersedes ENV 12290:1996 English version Advanced technical ceramics - Mechanical properties of ceramic composites at high temperature under inert atmosphere - Determination of compression properties Cramiques techniques avances - Proprits mcaniques des cra
7、miques composites haute temprature en atmosphre neutre - Dtermination des caractristiques en compression Hochleistungskeramik - Mechanische Eigenschaften von keramischen Verbundwerkstoffen bei hoher Temperatur in inerter Atmosphre - Bestimmung der Eigenschaften unter Druck This European Standard was
8、 approved by CEN on 12 May 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. Up-to-date lists and bibliographical references concerning such nation
9、al 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 under the responsibility of a CEN member into its own language and noti
10、fied 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, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherl
11、ands, 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 Stassart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any fo
12、rm and by any means reserved worldwide for CEN national Members. Ref. No. EN 12290:2005: ELicensed Copy: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 12290:2005 (E) 2 Contents page Foreword3 1 Scope 4 2 Normative references 4 3 Terms, definitions and symbols.4 4 Pri
13、nciple6 5 Apparatus .6 5.1 Test machine6 5.2 Load train6 5.3 Gastight test chamber.7 5.4 Set-up for heating 7 5.5 Extensometer .7 5.6 Temperature measurement devices 7 5.7 Data recording system 8 5.8 Micrometers8 6 Test specimens8 6.1 General8 6.2 Compression between platens.8 6.3 Test specimen used
14、 with grips 9 7 Test specimen preparation.12 7.1 Machining and preparation.12 7.2 Number of test specimens12 8 Test procedures.12 8.1 Test set-up: Temperature considerations.12 8.2 Test set-up: other considerations13 8.3 Testing technique 14 8.4 Test validity 15 9 Calculation of results 15 9.1 Test
15、specimen origin.15 9.2 Compression strength 15 9.3 Strain at maximum compression force .16 9.4 Proportionality ratio or pseudo-elastic modulus, elastic modulus 16 10 Test report 17 Annex A (normative) Buckling: How to proceed when buckling is suspected.18 A.1 Preliminary room temperature test18 A.2
16、Test with two different specimens.18 Bibliography 19 Licensed Copy: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 12290:2005 (E) 3 Foreword This document (EN 12290:2005) has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics”, the secretaria
17、t of which is held by BSI. This 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 December 2005, and conflicting national standards shall be withdrawn at the latest by December 2005. This document supers
18、edes ENV 12290:1996. According to the CEN/CENELEC Internal Regulations, 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, Irela
19、nd, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 12290:2005 (E) 4 1 Scope This European Standard spe
20、cifies the conditions for determination of compression properties of ceramic matrix composite 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 avoidi
21、ng changes of the material to be tested due to chemical reaction with its environment during the test. This European Standard 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
22、 principal axis of reinforcement. Two types of compression are distinguished: a) compression between platens; b) compression using grips. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited app
23、lies. 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 uniaxial testing. EN 60584-1, Thermocouples - Part 1: Reference tables (IEC 60584-1:1995). EN
24、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 Verification and calibration of the force measuring system (ISO 7500-1:2004). ISO 3611, Micrometer c
25、allipers for external measurement. 3 Terms, definitions and symbols For the purposes of this European Standard, the following terms and definitions apply. 3.1 test temperature, T temperature of the test piece at the centre of the gauge length 3.2 calibrated length, l part of the test specimen that h
26、as uniform and minimum cross-section area 3.3 gauge length, Loinitial distance between reference points on the test specimen in the calibrated length Licensed Copy: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 12290:2005 (E) 5 3.4 controlled temperature zone part of
27、 the calibrated length including the gauge length where the temperature is within a range of 50 C of the test temperature 3.5 initial cross-section area, Aoinitial cross-section area of the test specimen within the calibrated length, at test temperature 3.6 longitudinal deformation, L decrease in th
28、e gauge length L between reference points under a compression force NOTE Its value at maximum force is denoted Lc,m. 3.7 compression strain, relative change in the gauge length defined as the ratio L/LoNOTE Its value at maximum force is denoted as c,m. 3.8 compression stress, compression force suppo
29、rted by the test specimen at any time in the test divided by the initial cross-section area (Ao) 3.9 maximum compression force, Fmhighest recorded compression force in a compression test on the test specimen when tested to failure 3.10 compression strength, c,mratio of the maximum compression force
30、(Fm) to the initial cross-section area (Ao) 3.11 proportionality ratio or pseudo-elastic modulus, Epslope 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 l
31、inear section in the stress-strain curve. For ceramic matrix composites that have a mechanical behaviour characterized by a linear section, the proportionality ratio is defined as: 121221),(p=E (1) where (1, 2) and (2, 2) lie near the lower and upper limits of the linear section of the stress-strain
32、 curve. The proportionality ratio or pseudo-elastic modulus is termed the elastic modulus, E, in the single case where the material has a linear behaviour from the origin. b) Material with no-linear section in the stress-strain curve. In this case only stress-strain couples can be fixed. Licensed Co
33、py: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontrolled Copy, (c) BSIEN 12290:2005 (E) 6 4 Principle A test specimen of specified dimensions is heated to the test temperature, and loaded in compression. The test is performed at constant crosshead displacement rate, or constant deformation
34、 rate. Force and longitudinal deformation are measured and recorded simultaneously. NOTE 1 The test duration is limited to reduce creep effects. NOTE 2 Constant loading rate is only allowed in the case of linear stress-strain behaviour up to failure. NOTE 3 In order to protect fixtures, it is recomm
35、ended to use constant crosshead displacement rate when the test is carried out until rupture. 5 Apparatus 5.1 Test machine The machine shall be equipped with a system for measuring the force applied to the test specimen which shall conform to grade 1 or better according to EN ISO 7500-1. NOTE This s
36、hould prevail during actual test conditions 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 a
37、nd the force transmitting system shall not change because of heating. There are two alternative means of load application. a) Compression platens are connected to the load cell and on the moving crosshead. The parallelism of these platens shall be better than 0,01 mm, in the loading area, at room te
38、mperature and they shall be perpendicular to the load direction. NOTE 1 The use of platens is not recommended for compression testing of 1D and 2D materials with low thickness due to buckling. NOTE 2 A compliant interlayer material between the test specimen and platens may be used for testing macros
39、copically inhomogeneous materials to ensure even contact pressure. This material should be chemically compatible with both test specimen and platen materials. b) Grips are used to clamp and load the test specimen. The grip design shall prevent the test specimen from slipping. The grips shall align t
40、he test specimen axis with that of the applied force. NOTE 3 Conformity with this requirement should be verified and documented according to, for example, the procedure described in reference 1. NOTE 4 The grips or the platens may either be in the hot zone of the furnace or outside the furnace. NOTE
41、 5 When grips or platens are outside the furnace, a temperature gradient exists between the centre of the specimen, which is at the prescribed temperature, and the ends that are at the same temperature as the grips or platens. Licensed Copy: Wang Bin, na, Tue Apr 10 07:27:40 GMT+00:00 2007, Uncontro
42、lled Copy, (c) BSIEN 12290:2005 (E) 7 5.3 Gastight test chamber The gastight chamber shall allow proper control of the test specimen environment in the vicinity of the test specimen during the test. The installation shall be such that the variation of load due to the variation of pressure is less th
43、an 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 pressure shall be chosen depending: on the material to be tested, on temperature, on the type of gas, and o
44、n 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, when applicable. 5.4 Set-up for heating The set-up for heating shall be constructed in such a way that the
45、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 test temperature. NOTE 1 The use of an extensometer with the greatest possible gauge length is recommended.
46、 The linearity tolerance shall be less than or equal to 0,15 % of the extensometer range used. The extensometer shall conform to class 1 or better of EN 10002-4. Two commonly used types of extensometer are the mechanical extensometer and the electro-optical extensometer. If a mechanical extensometer
47、 is used, the gauge length shall be the initial 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 temperature. Temperature and/or environment induced structural changes in the r
48、od 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 extensometer that may occur as a result of operating under conditions dif
49、ferent from calibration. NOTE 3 Rod pressure onto the test specimen should be the minimum necessary to prevent slipping of the extensometer rods. If an electro-optical extensometer is used, electro-optical measurements in transmission require reference marks on the test specimen. For this purpose rods or flags shall be attached to the surface perpendicular 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 test specim
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