BS EN 1893-2005 Advanced technical ceramics - Mechanical properties of ceramic composites at high temperature in air at atmospheric pressure - Determination of tensile properties《高.pdf

1、BRITISH STANDARD BS EN 1893:2005 Advanced technical ceramics Mechanical properties of ceramic composites at high temperature in air at atmospheric pressure Determination of tensile properties The European Standard EN 1893:2005 has the status of a British Standard ICS 81.060.30 Licensed Copy: Wang Bi

2、n, na, Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIBS EN 1893:2005 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 45997 7 National foreword This British Standard is the official English langua

3、ge version of EN 1893:2005. It supersedes DD ENV 1893:1996 which is withdrawn.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 r

4、equest to 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 BS

5、I Electronic 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 enquire

6、rs to understand 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 docume

7、nt comprises a front cover, an inside front cover, the EN title page, pages 2 to 17 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

8、:15:14 BST 2005, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1893 April 2005 ICS 81.060.30 Supersedes ENV 1893:1996 English version Advanced technical ceramics - Mechanical properties of ceramic composites at high temperature in air at atmospheric pressure - Deter

9、mination of tensile properties Cramiques techniques avances - Proprits mcaniques des cramiques composites haute temprature sous air la pression atmosphrique - Dtermination des caractristiques en traction Hochleistungskeramik - Mechanische Eigenschaften von keramischen Verbundwerkstoffen bei hoher Te

10、mperatur in Luft bei Atmosphrendruck - 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 nation

11、al standard without any alteration. 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

12、other language made by translation 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

13、, France, Germany, Greece, Hungary, 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 NO

14、RMUNG Management Centre: rue de Stassart, 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 1893:2005: E Licensed Copy: Wang Bin, na, Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIEN 1893:2005 (E) 2

15、Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms, definitions and symbols.4 4 Principle6 5 Apparatus .6 6 Test specimens8 7 Test specimen preparation.10 8 Test procedures.11 9 Calculation of results 13 10 Test report 15 Annex A (informative) Test specimen for use with optical exten

16、sometry.16 Bibliography 17 Licensed Copy: Wang Bin, na, Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIEN 1893:2005 (E) 3 Foreword This document (EN 1893:2005) has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics”, the secretariat of which is held by BSI. This Eu

17、ropean Standard shall be given the 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 1893:1996. According to the

18、 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, Ireland, Italy, Latvia, Lithuania, Luxembo

19、urg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: Wang Bin, na, Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIEN 1893:2005 (E) 4 1 Scope This document specifies the conditions for determination of tensile pr

20、operties of ceramic matrix composite materials with continuous fibre reinforcement for temperatures up to 1 700 C in air at atmospheric pressure. This document applies to all ceramic matrix composites with a continuous fibre reinforcement, unidirectional (1D), bi-directional (2D), and tri-directiona

21、l (xD, with 2 x 3), loaded along one principal axis of reinforcement. NOTE 1 In most cases, ceramic matrix composites to be used at high temperature in air are coated with an anti- oxidation coating. NOTE 2 The purpose of this document is to determine the tensile properties of a material when it is

22、placed under an oxidizing environment but not to measure material oxidation. 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 edition of the refer

23、enced document (including any amendments) applies. 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/comp

24、ression testing machines Verification 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,

25、T temperature of the test piece at the centre of the gauge length 3.2 calibrated length, I part of the test specimen that 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

26、 zone part of the calibrated length 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 areas of the test specimen within the calibrated length, at test temperature Licensed Copy: Wang Bin, na,

27、 Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIEN 1893:2005 (E) 5 3.6 apparent cross-section area, S o apptotal area of the cross-section3.7 effective cross-section area, S o efftotal area corrected by a factor, to account for the presence of an anti-oxidative protection 3.8 longitudinal d

28、eformation, A increase in the gauge length between reference points under a tensile force 3.9 longitudinal deformation under maximum tensile force, A mincrease in the gauge length between reference points under maximum tensile force 3.10 tensile strain, relative change in the gauge length defined as

29、 the ratio A/L o3.11 tensile strain under maximum force, m . relative change in the gauge length defined as the ratio A/L ounder the maximum force 3.12 tensile stress, tensile force supported by the test specimen at any time in the test divided by the initial cross-section area (S o ) 3.13 apparent

30、tensile stress, app tensile force supported by the test specimen at any time in the test divided by the apparent cross-section area (or total cross-section area) 3.14 effective tensile stress, eff tensile force supported by the test specimen at any time in the test divided by the effective cross-sec

31、tion area (S o eff ) 3.15 maximum tensile force, F mhighest recorded tensile force in a tensile test on the test specimen when tested to failure 3.16 3.16.1 tensile strength, mratio of the maximum tensile force to the initial cross-section area (S o ) 3.16.2 apparent tensile strength, m app ratio of

32、 the maximum tensile force to the apparent cross-section area (or total cross-section area) 3.16.3 effective tensile strength, m eff ratio of the maximum tensile force to the effective cross-section area Licensed Copy: Wang Bin, na, Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIEN 1893:200

33、5 (E) 6 3.17 proportionality ratio 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 c

34、urve; For ceramic matrix composites that have a mechanical behaviour characterized by a linear section, the proportionality ratio is defined as: () () () 1 2 1 2 2 1 , = EP (1) where () 2 1 , and() 2 2 , lie near the lower and the upper limits of the linear section of the stress-strain curve. The pr

35、oportionality ratio or pseudo-elastic 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. 3.18 apparent proportionality ratio, EP

36、appslope of the linear section of the stress-strain curve, if any, when the apparent tensile stress is used 3.19 effective proportionality ratio, EP effslope of the linear section of the stress-strain curve, if any, when the effective tensile stress is used 4 Principle A test specimen of specified d

37、imensions 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 measured and recorded simultaneously. NOTE 1 The test duration is limited

38、 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 constant deformation rate is recommended to obtain the complete curve. 5

39、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. NOTE This prevails during actual test conditions, e.g. gas pressure, temperature. Licensed Copy: Wang Bin, na,

40、Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIEN 1893:2005 (E) 7 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

41、force transmitting system, shall 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 in accordance with, for example, the procedure described in the HTMTC code of practice 1

42、. The grip design shall prevent the 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 specime

43、n design and on alignment requirements. 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

44、 and the ends which are at the same temperature as the grips. 5.3 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. 5.4 Extensometer The extensometer shall be capable of continuous

45、ly recording the longitudinal deformation at test temperature. 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 mechanical extensometer

46、and the electro-optical extensometer. If a mechanical extensometer is used, the gauge length shall be 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 temperature. Temperat

47、ure 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 extensometer that may occur as a r

48、esult 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. Licensed Copy: Wang Bin, na, Fri Aug 05 04:15:14 BST 2005, Uncontrolled Copy, (c) BSIEN 1893:2005 (E) 8 If an elect

49、ro-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 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 test specimen material and the test temperature and shall not modify