1、August 2014 Translation by DIN-Sprachendienst.English price group 11No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS
2、 25.220.60!%:;,“2232409www.din.deDDIN EN 13523-7Coil coated metals Test methods Part 7: Resistance to cracking on bending (T-bend test);English version EN 13523-7:2014,English translation of DIN EN 13523-7:2014-08Bandbeschichtete Metalle Prfverfahren Teil 7: Widerstandsfhigkeit gegen Rissbildung bei
3、m Biegen (T-Biegeprfung);Englische Fassung EN 13523-7:2014,Englische bersetzung von DIN EN 13523-7:2014-08Tles prlaques Mthodes dessai Partie 7: Rsistance la fissuration par pliage (essai de pliage en T);Version anglaise EN 13523-7:2014,Traduction anglaise de DIN EN 13523-7:2014-08SupersedesDIN EN 1
4、3523-7:2001-12www.beuth.deDocument comprises 18 pagesIn case of doubt, the German-language original shall be considered authoritative.07.14DIN EN 13523-7:2014-08 2 A comma is used as the decimal marker. National foreword This document (EN 13523-7:2014) has been prepared by Technical Committee CEN/TC
5、 139 “Paints and varnishes”, (Secretariat: DIN, Germany), Working Group WG 9 “Testing of coil coated metals” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was the Normenausschuss Beschichtungsstoffe und Beschichtungen (DIN Standards Committee Coatings and Coati
6、ng Materials), Working Committee NA 002-00-07 AA Allgemeine Prfverfahren fr Beschichtungsstoffe und Beschichtungen. Amendments This standard differs from DIN EN 13523-7:2001-12 as follows: a) details on the brands of the tape used have been added; b) an information concerning the conditioning of the
7、 specimen has been added; c) in addition to the use of a magnifying glass 10, the evaluation is to be carried out with normal corrected vision. Previous editions DIN EN 13523-7: 2001-12 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 13523-7 June 2014 ICS 25.220.60 Supersedes EN 13523-7:2001Eng
8、lish Version Coil coated metals - Test methods - Part 7: Resistance to cracking on bending (T-bend test) Tles prlaques - Mthodes dessai - Partie 7: Rsistance la fissuration par pliage (essai de pliage en T) Bandbeschichtete Metalle - Prfverfahren - Teil 7: Widerstandsfhigkeit gegen Rissbildung beim
9、Biegen (T-Biegeprfung) This European Standard was approved by CEN on 7 May 2014. 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 b
10、ibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre 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 res
11、ponsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav R
12、epublic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NO
13、RMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 13523-7:2014 EEN 13523-7:2014 (E) 2 Contents Page Foreword 3 1 Scope 5
14、 2 Normative references 5 3 Terms and definitions .5 4 Principle 5 5 Apparatus .6 6 Sampling 11 7 Test panels 11 8 Procedure 12 8.1 General . 12 8.2 Methods for practical (industrial) use 12 8.2.1 Folding method . 12 8.2.2 Mandrel method 13 8.3 Method for laboratory purposes . 14 9 Expression of res
15、ults . 14 10 Precision 14 11 Test report . 14 Bibliography . 16 DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 3 Foreword This document (EN 13523-7:2014) has been prepared by Technical Committee CEN/TC 139 “Paints and varnishes”, the secretariat of which is held by DIN. This European Standard shall be g
16、iven the status of a national standard, either by publication of an identical text or by endorsement, at the latest by December 2014, and conflicting national standards shall be withdrawn at the latest by December 2014. Attention is drawn to the possibility that some of the elements of this document
17、 may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 13523-7:2001. The main technical changes are: a) details on the brands of the tape used were added; b) a remark on conditioning was added;
18、 c) in addition to use a 10 magnifying glass, the evaluation shall be carried out with normal corrected vision. EN 13523, Coil coated metals Test methods, consists of the following parts: Part 0: General introduction Part 1: Film thickness Part 2: Gloss Part 3: Colour difference Instrumental compari
19、son Part 4: Pencil hardness Part 5: Resistance to rapid deformation (impact test) Part 6: Adhesion after indentation (cupping test) Part 7: Resistance to cracking on bending (T-bend test) Part 8: Resistance to salt spray (fog) Part 9: Resistance to water immersion Part 10: Resistance to fluorescent
20、UV radiation and water condensation Part 11: Resistance to solvents (rubbing test) Part 12: Resistance to scratching Part 13: Resistance to accelerated ageing by the use of heat Part 14: Chalking (Helmen method) DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 4 Part 15: Metamerism Part 16: Resistance to
21、abrasion Part 17: Adhesion of strippable films Part 18: Resistance to staining Part 19: Panel design and method of atmospheric exposure testing Part 20: Foam adhesion Part 21: Evaluation of outdoor exposed panels Part 22: Colour difference Visual comparison Part 23: Resistance to humid atmospheres c
22、ontaining sulfur dioxide Part 24: Resistance to blocking and pressure marking Part 25: Resistance to humidity Part 26: Resistance to condensation of water Part 27: Resistance to humid poultice (Cataplasm test) Part 29: Resistance to environmental soiling (Dirt pick-up and striping) According to the
23、CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hun
24、gary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 5 1 Scope This part of EN 13523 specifies the procedure for d
25、etermining the resistance to cracking of an organic coating on a metallic substrate when bent through 135 to 180. The degree of adhesion may also be evaluated. Both folding and mandrel methods are considered. The folding method is more often used for practical purposes but where more precise determi
26、nations are required, the mandrel method is recommended. The cylindrical bend method may also be used for a pass/fail decision by using an agreed mandrel. The choice of the appropriate test method is limited by the thickness and/or the hardness of the substrate. The feasibility of the test depends o
27、n the type and thickness of the substrate. During the procedure, the mandrel should not deform. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited app
28、lies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 13523-0:2014, Coil coated metals Test methods Part 0: General introduction EN 23270, Paints and varnishes and their raw materials Temperatures and humidities for conditioning and testin
29、g (ISO 3270) EN 60454-2, Pressure-sensitive adhesive tapes for electrical purposes Part 2: Methods of test (IEC 60454-2) 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 13523-0:2014 and the following apply. 3.1 metal thickness total thickness of the s
30、ubstrate including any metallic coating and excluding any organic coating 4 Principle The coated test specimen is bent parallel to the direction of rolling through 135 to 180 over a period of 1 s to 2 s around various radii with the coating on the outside of the bend. Close contact is maintained bet
31、ween the test specimen and either the wedge or mandrel to ensure a uniform bend. Any bending device allowing the required smooth and uniform bending may be used. The minimum bending radius to which the specimen can be bent without cracking of the organic coating determines the resistance to cracking
32、 on bending through 135 to 180. DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 6 The minimum bending radius to which the specimen can be bent without loss of adhesion determines the resistance to loss of adhesion on bending through 135 to 180. 5 Apparatus 5.1 Bending device 5.1.1 for the folding method
33、Vice or suitable bend forming apparatus as shown in Figure 1. 5.1.2 for the mandrel method Bending device, appropriate to the metal thickness, hardness, and panel size: cylindrical mandrel: see Figure 2; conical mandrel: see Figure 3; conical wedge mandrel: see Figure 4; the conical wedge mandrel ma
34、y be driven manually (see Figure 5) or pneumatically (see Figure 6). 5.2 Magnifying glass 10. 5.3 Transparent pressure-sensitive adhesive tape, 25 mm wide, with an adhesion strength of (10 1) N per 25 mm width when tested in accordance with EN 60454-2. DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 7 Ke
35、y A apparatus jaws B bending plate C clamping screws D test specimen 1 direction of movement Figure 1 Practical test (P) folding method DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 8 Figure 2 Laboratory test (L) cylindrical bend DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 9 Figure 3 Laboratory test (L)
36、 conical bend Dimensions in millimetres NOTE In this conical wedge mandrel, the distance between each increase of 1 mm radius is 45 mm. This distance should always be equal to or larger than 30 mm so that eventual creep of cracks does not substantially influence the test results. Figure 4 Conical we
37、dge mandrel DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 10 Figure 5 Practical test (P) hand operated apparatus DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 11 NOTE Schematic diagram of mechanical test equipment. Key 1 wedge 2 test specimen 3 rubber 4 pneumatic cylinder approximately 6 bar Figure 6 Prac
38、tical test (P) pneumatically driven 6 Sampling See EN 13523-0. Use only flat strip of such a size that the required procedure can be executed and the results obtained are representative of the end use of the material. 7 Test panels See EN 13523-0. DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 12 Becaus
39、e of possible burrs, up to 5 mm on extreme edges shall be ignored during evaluation. The coating surface shall be free of oil and other foreign matter that might influence the flexibility of the coating or interfere with the observation for cracking or loss of adhesion. 8 Procedure 8.1 General Measu
40、re the resistance of the organic coating to cracking at ambient temperature. For more accurate measurements, as required for instance in the case of dispute, the temperature shall be (23 2) C and the relative humidity (50 5) %, in accordance with EN 23270. Conditioning is carried out in accordance w
41、ith EN 13523-0:2014, Clause 6. The coating under test shall always be at the outside of the bend. The bending shall be carried out over a period of 1 s to 2 s. The bends shall be examined using normal corrected vision and the magnifying glass (5.2) immediately after bending. If necessary, a second i
42、nspection may be agreed after a specified ageing (see, for example, EN 13523-13) of either the flat material before bending or the bend itself. The adhesion may also be evaluated as follows: Remove two complete laps from a reel of the adhesive tape (5.3) and discard. Remove an additional length at a
43、 steady rate and cut a piece, approximately 75 mm long. Place the centre of the tape along the length of the bend and smooth the tape into place over for a distance of at least 20 mm either side with a finger. To ensure good contact with the coating, rub the tape firmly with a fingertip. The colour
44、of the coating seen through the tape is a useful indication of overall contact. Within 5 min of applying the tape, remove the tape by holding the free end and pulling it off steadily in 0,5 s to 1 s at an angle that is as close as possible to 60 to the panel. In cases of dispute, one of the followin
45、g test methods shall be agreed between the interested parties. 8.2 Methods for practical (industrial) use 8.2.1 Folding method The apparatus (5.1.1) shall be firmly secured near the edge of a bench, so that the handle can be operated freely. The test specimen shall be firmly clamped between the jaws
46、 of the device or vice, with the painted surface to be evaluated facing downwards, or, in the case of the vice, facing the operator. The handle operating the bending plate shall be lifted smoothly over a period of 1 s to 2 s. This operation shall be repeated with the test specimen being examined imm
47、ediately after each bend, with normal corrected vision and the magnifying glass (5.2). In the instance of a vice being used where no bending plate is available, even pressure shall be applied with both thumbs, to ensure a smooth and uniform bending operation (see Figure 7). This method can result in
48、 peaking of the bend. Therefore, for more precise results one of the other methods should be used. DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 13 Key A vice jaws B test specimen C thumb 1 direction of movement 2 T bends ECCA 3 correct 4 incorrect 5 rolling direction of coil Figure 7 T-bend test 8.2.2
49、 Mandrel method The test specimen shall be placed on an appropriate thick and flexible rubber mat, the painted surface facing towards the rubber. Either by hand or pneumatically, either the cylindrical mandrels in decreasing radius-order DIN EN 13523-7:2014-08 EN 13523-7:2014 (E) 14 or the conical wedge mandrel (see Figures 4, 5 and 6) shall be pressed deep enough into the rubber to ensure the proper deformation of the test spec
