1、DD CEN/TS15867:2009ICS 81.060.30NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWDRAFT FOR DEVELOPMENTAdvanced technicalceramics Ceramiccomposites Guideto the determinationof the degree ofmisalignment inuniaxial mechanicaltestsLicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARD
2、S, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIThis Draft for Developmentwas published under theauthority of the StandardsPolicy and StrategyCommittee on 30 April2009 BSI 2009ISBN 978 0 580 63940 1Amendments/corrigenda issued since publicationDate CommentsDD CEN/TS 15867:2009National forewordThis Dr
3、aft for Development is the UK implementation of CEN/TS15867:2009.This publication is not to be regarded as a British Standard.It is being issued in the Draft for Development series of publications andis of a provisional nature. It should be applied on this provisional basis,so that information and e
4、xperience of its practical application can beobtained.Comments arising from the use of this Draft for Development arerequested so that UK experience can be reported to the internationalorganization responsible for its conversion to an international standard.A review of this publication will be initi
5、ated not later than 3 years afterits publication by the international organization so that a decision can betaken on its status. Notification of the start of the review period will bemade in an announcement in the appropriate issue of Update Standards.According to the replies received by the end of
6、the review period,the responsible BSI Committee will decide whether to support theconversion into an international Standard, to extend the life of theTechnical Specification or to withdraw it. Comments should be sent tothe Secretary of the responsible BSI Technical Committee at BritishStandards Hous
7、e, 389 Chiswick High Road, London W4 4AL.The UK participation in its preparation was entrusted to TechnicalCommittee RPI/13, Advanced technical ceramics.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all t
8、he necessary provisionsof a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009TECHNICAL SPE
9、CIFICATIONSPCIFICATION TECHNIQUETECHNISCHE SPEZIFIKATIONCEN/TS 15867March 2009ICS 81.060.30English VersionAdvanced technical ceramics - Ceramic composites - Guide tothe determination of the degree of misalignment in uniaxialmechanical testsCramiques techniques avances - Cramiquescomposites - Guide p
10、our dterminer le degr de non-alignement des essais mcaniques uniaxiauxHochleistungskeramik - Keramische Verbundwerkstoffe -Anleitung zur Bestimmung der Fluchtungsfehler beimechanischen Prfungen mit einachsiger BeanspruchungThis Technical Specification (CEN/TS) was approved by CEN on 3 February 2009
11、for provisional application.The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit theircomments, particularly on the question whether the CEN/TS can be converted into a European Standard.CEN members are required to a
12、nnounce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS availablepromptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)until the final decision about the possible conversion of
13、the CEN/TS into an EN is reached.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Roman
14、ia, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: Avenue Marnix 17, B-1000 Brussels 2009 CEN All rights of exploitation in any form and by any means reservedworldw
15、ide for CEN national Members.Ref. No. CEN/TS 15867:2009: ELicensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 2 Contents Page Foreword 31 Scope 42 Normative references 43 Terms and definitions .44 Principle 55 A
16、pparatus .65.1 Test machine 65.2 Strain gauges .65.3 Data recording system 75.4 Micrometers 76 Reference test specimens 77 Reference test specimens preparation .97.1 Adhesion of strain gauges 97.2 Reference test specimen validity .98 Test procedure .98.1 General 98.2 Correction of the torsion defect
17、 .98.3 Correction of the C defect 108.4 Correction of the S defect 118.5 Final verification before starting a series of measurements on CMCs . 129 Test report . 12Bibliography . 14Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009C
18、EN/TS 15867:2009 (E) 3 Foreword This document (CEN/TS 15867:2009) has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics”, the secretariat of which is held by BSI. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
19、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 announce this Technical Specification: Austria, Belgium, Bulgaria, C
20、yprus, 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 and the United Kingdom. Licensed Copy: Wang Bin, ISO/EXCHA
21、NGE CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 4 1 Scope This Technical Specification provides guidance on: verifying the degree of misalignment of the load train of test machines, using a reference test specimen uniformly loaded in tension
22、 or in compression; correcting for defects caused by, e.g. torsion and bending. This document is not intended to provide a quantitative and acceptable limit before the testing of ceramic matrix composites with a fibre reinforcement: unidirectional (1D), bidirectional (2D) and tridirectional (xD, wit
23、h 2 x 3) loaded along one principle axis of reinforcement. This limit depends on the sensitivity of each type of composite to the misalignment defect. NOTE 1 This limit is to be defined between the testing establishment and the customer. NOTE 2 Monolithic ceramics are very sensitive to misalignment
24、defects, while ceramic matrix composites (CMCs) in general are moderately sensitive to them. 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 edit
25、ion of the referenced document (including any amendments) applies. CEN/TR 13233:2007, Advanced technical ceramics Notations and symbols EN ISO 7500-1, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibration of the
26、force measuring system (ISO 7500-1:2004) EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025:2005) ISO 3611, Micrometer callipers for external measurement 3 Terms and definitions For the purposes of this document, the terms and definitions
27、 given in CEN/TR 13233:2007 and the following apply. 3.1 calibrated length l part of the reference test specimen which has a uniform and minimum cross section area 3.2 width b width of the reference test specimen in the calibrated length 3.3 thickness h thickness of the reference test specimen in th
28、e calibrated length Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 5 3.4 Type of defects 3.4.1 C type magnitude angle between the loading axis of each of the two grips (see Figure 1) 3.4.2 S type magnitude
29、d distance between the loading axis when they are parallel (see Figure 2) 3.4.3 torsion defect magnitude angle between the gripping planes (see Figure 3) 4 Principle A rectangular cross section of a reference test specimen equipped with 10 strain gauges is loaded in tension or in compression up to a
30、 load corresponding to 10 % of the nominal load capacity of the load cell used for the tests of CMCs. The stress corresponding to this value does not exceed 50 % of the elasticity limit of the material used for the reference test specimen. The readings obtained from the strain gauges bonded on the c
31、alibrated length of the reference test specimen allow the degree of misalignment to be determined. The positioning of strain gauges is such that it indicates the magnitude of defects. These magnitudes permit the practical correction of the different types of defects: bending defects, either C (Figur
32、e 1) or S (Figure 2); or torsion (Figure 3). Indications for correction are obtained by comparing the experimental readings of the strain gauges to values from charts established from numerical simulations. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (
33、c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 6 Figure 1 C defect magnitude Figure 2 S defect magnitude Key 1 lower grip 2 upper grip Figure 3 Torsion defect magnitude 5 Apparatus 5.1 Test machine The configuration of the test machine, including the load train and load cell shall be identical to t
34、he test machine used for the tests on the CMCs and shall be in accordance with EN ISO 7500-1. 5.2 Strain gauges The principle of this method requires the use of strain gauges with an active surface equal to or smaller than 4 x 2 mm2. Furthermore, the distance between the edge of the test reference s
35、pecimen and the longitudinal axis of the strain gauge shall be such as to avoid edge effects. A minimum distance of 2 mm is required. Care shall be taken to ensure that the strain gauge readings are not influenced by the surface preparation and the adhesive used. Licensed Copy: Wang Bin, ISO/EXCHANG
36、E CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 7 5.3 Data recording system A calibrated recorder may be used to record load/strain curves. The use of a data recording system combined with an analogue recorder is recommended. All strain measur
37、ing equipment and data acquisition systems shall be calibrated. They shall have an accuracy to within 0,5 % of the indicated reading or 3 microstrain, whichever is greater, and a resolution of 1 microstrain. 5.4 Micrometers Micrometers used for the measurement of the dimensions of the reference test
38、 specimen shall be in accordance with ISO 3611. 6 Reference test specimens The degree of misalignment of the load train of the test machine is verified by performing tests at room temperature with the following reference test specimen: dimensions: see Figure 4; material: steel ISO reference; locatio
39、n of the strain gauges: see Figure 4. If another reference test specimen is used, it is necessary to establish a new series of charts. Plan parallelism of the faces 0,02 mm. Dimensions of the strain gauges, in millimetres: 2 4 Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/08/2009 01:54,
40、Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 8 NOTE Gauge n 5 is a rosette allowing measurements of strains parallel to 1 and to 45. Figure 4 Dimensions of the reference test specimen and location of the strain gauges Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/0
41、8/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 9 7 Reference test specimens preparation 7.1 Adhesion of strain gauges It is essential to protect strain gauges and adhesives from effects due to moisture and other degrading contaminants. Therefore it is recommended t
42、hat, after installation of the strain gauges, a layer of protective coating material such as strain-gauge-grade silicone rubber is applied. 7.2 Reference test specimen validity Periodically check the response of the strain gauges by comparing the Youngs modulus of the steel (from which the reference
43、 test specimen is made) determined for each location of the strain gauges, to the value of the Young modulus determined during the first utilization of the reference test specimen by the same method. The difference between these two values shall not exceed 5 %. This value shall be indicated more acc
44、urately when more experimental results are made available. It is recommended to do this verification once a year. 8 Test procedure 8.1 General The procedure consists of the following sequence. 8.2 Correction of the torsion defect The reference test specimen is gripped while keeping the uniaxial load
45、 at 0, by using a specific mounting tool that secures a strict parallelism between the loading axis and the longitudinal axis of the reference test specimen. To check it, compare responses given by gauges 1 and 2. Record the reading of strain gauges at position 5 and calculate the distortion (+45- -
46、45). This value allows the torsion defect to be determined using chart 1 (see Figure 5). If this value is higher than the authorized limit, a correction of the angle between the two grips shall be made. The above procedure is repeated until the value of the angle is less or equal to the authorized l
47、imit. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 12/08/2009 01:54, Uncontrolled Copy, (c) BSIDD CEN/TS 15867:2009CEN/TS 15867:2009 (E) 10 NOTE is in C and the other dimensions are in millimetres. Figure 5 Chart 1: torsion defect 8.3 Correction of the C defect Load the reference test spec
48、imen to stretch the load train. Record the longitudinal readings of the strain gauges located at position 4 (1,4) and 5 (1,5): see specimen drawing in Figure 4 given by strain gauges no. 4 and no. 5 respectively and see dimensions in Table 1. Calculate the value of (1,4- 1,5) and determine the C def
49、ect using chart 2 (see Figure 6). If this value is higher than the authorized limit, a correction of the angle between the loading axis of each of the two grips shall be made. The above procedure is repeated until the value of the angle is less or equal to the authorized limit. Then unload the reference test specimen. Table 1 Strain gauges dimensions Dimensionsmm Tolerances mm l, length with strain gauges 100 0,1 t, thickn
