BS EN 15340-2007 Thermal spraying - Determination of shear load resistance of thermally sprayed coatings《热喷涂 热喷涂层耐剪切负荷的测定》.pdf

1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58thermally sprayed coatingsThe European Standard EN 15340:2007 has the status of a British StandardI

2、CS 25.220.20Thermal spraying Determination of shear load resistance of BRITISH STANDARDBS EN 15340:2007BS EN 15340:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 June 2007 BSI 2007ISBN 978 0 580 50885 1Amendments issued since publicat

3、ionAmd. No. Date Commentscontract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK implementation of EN 15340:2007.The UK participation in its

4、preparation was entrusted to Technical Committee STI/40, Thermally sprayed inorganic finishes.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a EUROPEAN STANDARDNORME EUROPE

5、NNEEUROPISCHE NORMEN 15340March 2007ICS 25.220.20English VersionThermal spraying - Determination of shear load resistance ofthermally sprayed coatingsProjection thermique - Dtermination de la rsistance aucisaillement des revtements obtenus par projectionthermiqueThermisches Spritzen - Bestimmung des

6、Scherbeanspruchungswiderstandes bei thermischgespritzten SchichtenThis European Standard was approved by CEN on 3 February 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard

7、without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other langua

8、ge made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,Fr

9、ance, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR N

10、ORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15340:2007: EEN 15340:2007 (E) 2 Contents Page Foreword3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and

11、 definitions .5 4 Equipment 6 5 Specimens 7 5.1 Shape 7 5.2 Preparation .8 5.3 Number of specimens to be tested9 6 Procedure .9 7 Results 9 8 Test report 9 Annex A (informative) Evaluation11 Annex B (informative) Coating systems and sources of error .14 B.1 Coating systems (bond/top coat).14 B.2 Fau

12、lts in testing .14 Bibliography 15 EN 15340:2007 (E) 3 Foreword This document (EN 15340:2007) has been prepared by Technical Committee CEN/TC 240 “Thermal spraying and thermally sprayed coatings”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national

13、 standard, either by publication of an identical text or by endorsement, at the latest by September 2007, and conflicting national standards shall be withdrawn at the latest by September 2007. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following co

14、untries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, S

15、pain, Sweden, Switzerland and United Kingdom. EN 15340:2007 (E) 4 Introduction The test is conducted to determine the shear load resistance of the bond between the spray deposit and the parent material (adhesive strength) and/or the strength of the coating itself (cohesive strength). If adhesive str

16、ength of the sprayed coating to the base material supersedes the cohesive strength, primarily the cohesive strength of the deposit is determined. During the test the coating is loaded parallel to the interface of coating/substrate. The test is used to evaluate the effects of parent material and spra

17、y material, surface preparation of the work piece before spraying, and the spraying conditions on the adhesive and/or cohesive strength of thermally sprayed coatings, or for quality control and routine supervision of the spray works. EN 15340:2007 (E) 5 1 Scope This European Standard specifies the p

18、rocedure for determination of the shear load resistance of thermally sprayed coatings, provided that a minimum thickness is given. Additionally this European Standard defines the shear load resistance and the designation of the fractures structure on the test specimen, which occurs when the shear ad

19、hesive or adhesive/ cohesive or cohesive strength of the coating or the coating system will be exceeded. The test report is the basis for comparative statements regarding shear load resistance and structure of fracture. NOTE The test for the determination of the shear load resistance is not recommen

20、ded for sprayed coatings thinner than approximately 150 m because the adjustment of shear distance becomes critical. 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 ref

21、erences, the latest edition of the referenced document (including any amendments) applies. EN 657:2005, Thermal spraying Terminology, classification EN ISO 7500-1, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibr

22、ation of the force-measuring system (ISO 7500-1:2004) ISO 1832, Indexable inserts for cutting tools Designation 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 657:2005 and the following apply. 3.1 shear strength FSa maximum force that causes fracture

23、 of the specimen in the interface coating/substrate NOTE This fracture mode is called “Mode 1”. 3.2 shear adhesive/cohesive strength FSa/c maximum force that causes mixed fracture partially within coating material and partially in the interface coating/substrate NOTE This fracture mode is called “Mo

24、de 2”. 3.3 shear cohesive strength FSc maximum force that causes fracture of the specimen within the coating material NOTE This fracture mode is called: EN 15340:2007 (E) 6 “Mode 3a” - if in case of hard coatings continuous blistering of small or larger pieces of the coating occurs; - if soft and/or

25、 porous coatings will be compressed and continuously scraped off; “Mode 3b” - if the fracture path runs within the coating especially parallel to the interface coating/substrate and the coating part under the shear plate detaches in one piece 3.4 shear energy ES area below the force displacement cur

26、ve provided by the shear test NOTE The energy ES up to the first shear force maximum can be calculated using the force-displacement curve provided by the shear test. The energy ES relates to the energy absorption of the coating-substrate system until failure. 3.5 shear distance d distance between in

27、terface coating/substrate and the edge of the shear plate 3.6 shear load resistance value of the first maximum of the load during the shear test process 4 Equipment The shear test may be performed using a universal testing machine in accordance with EN ISO 7500-1 class 2.5 or using stand alone desk

28、top machine which fulfils the corresponding requirements for accuracy and reproducibility. The construction of the testing machine shall be able to apply a force required for the operation. The principle of the testing set up is demonstrated in Figure 1. EN 15340:2007 (E) 7 Key 1 load cell 6 specime

29、n holder 2 guided punch 7 displacement gauge 3 shear plate (cutting tool) 8 data processing 4 coating 9 test load 5 specimen Figure 1 Principle of shear test An exact fixation and alignment of the specimen in the specimen holder is necessary and any movement of the specimen during the shear test sha

30、ll be avoided. The shear plate is preferentially made of hard metal. A suitable cutting plate without “swarf crusher” (ISO 1832 standardized e.g. SP EW 120408 (turning, 110clearance angle) or LC EW 1904PPF (milling, 70clearance angle) ensures proper test conditions. The shear plate is fixed in a sui

31、table manner to a punch or cantilever that allows a movement during loading in the guide ways without deviations or friction that affects the measured shear force. The edge of the shear plate shall be parallel to the interface coating/substrate and parallel to the upper face of the specimen. Thus a

32、uniform loading of the coating is ensured. 5 Specimens 5.1 Shape The dimensions of the specimen for the determination of the shear load resistance of sprayed coatings are shown in Figure 2. EN 15340:2007 (E) 8 Dimensions in millimetres Key 1 area to be coated Figure 2 Dimensions of the specimen The

33、mentioned tolerances shall be complied with for measuring/adjusting the shear distance even from the back side of the specimens. For tolerances not specified 0,1 mm shall apply. After surface preparation the coating is sprayed to the front area of 5 mm 10 mm. When the specimens are coated in a rotat

34、ing specimen holder safe fastening against centrifugal forces shall be ensured e.g. form-locking by pin and hole or notch, as shown in Figure 3. Dimensions in millimetres Figure 3 Examples of specimen layout for form-locking safety of specimens during rotational coating 5.2 Preparation The specimen

35、is made of the specified material and shall be pre-treated in the same way as the work piece in practice. After surface preparation and before spraying, the length of the specimen has to be measured as a reference. The coating or the coating system is applied to the front face 5 mm 10 mm. No spray m

36、aterial shall be deposited on the other sides. The coating thickness shall be constant. Spray conditions shall be equal to those of practical work. For spraying a set of specimens they may be inserted as a batch in an adequate specimen holder. In that case it has to be guaranteed that each specimen

37、is mechanically separated, for example by thin copper foils. The separating elements shall not reach the coating area. Unavoidable overspray on the sides of the specimen shall be removed by abrasive paper (120 grit recommended) moving carefully from the coating to the substrate. Care shall be taken

38、to ensure the perpendicular position of specimen faces after cleaning. Other post treatments should be done only if it belongs to the treatment of the work piece in practice. Before carrying out the test, the coating thickness should be measured non-destructively or by metallographic examination on

39、an accompanying specimen. Care shall be taken when measuring the coating thickness by slide gauge in order to avoid that measured values are not overestimated due to coating roughness and/or loosely bonded particles on the surface. EN 15340:2007 (E) 9 5.3 Number of specimens to be tested For statist

40、ical reasons, at least five specimens, spray deposited in one cycle, should be tested. 6 Procedure Before performing the tests, the edge of the shear plate shall be inspected to prove that no damage has occurred during the preceding loading. The coated specimen is inserted into the specimen holder o

41、f the test device. Concerning shear distance the roughness of the specimen shall be taken into account. Thus, the shear distance d shall be 50 m 20 m (see Figure 4). Within this range the distance does not have a significant influence on the result. Then the specimen is securely clamped. Any movemen

42、t of the specimen during loading, lateral, back, or tilting shall be avoided. The coating is loaded according to Figures 1 and 4 by thrust of the shear plate at a constant rate and without jerks until fracture occurs and the recorded load decreases. A suitable speed of the shear plate is about 50 m/

43、s. Key 1 specimen 3 shear plate 2 shear force d shear distance Figure 4 Shear distance d 7 Results The shear load resistance is taken from the first maximum of the force displacement curve. Typical force displacement curves are schematically shown in Annex A, Figures A.1 to A.5. After completing the

44、 tests, the arithmetic mean value in N and standard deviation of the determined shear forces (FSa, FSc, or FSa/c) for all evaluated specimens shall be calculated. The standard deviation of the test shall be less than 10 %. Otherwise the test shall be repeated. The fractures structure is important fo

45、r the evaluation of the shear load resistance. Therefore the fracture mode shall be indicated in the test report. 8 Test report The test report shall contain the following information for every specimen tested in accordance with this European Standard: a) inspection body, inspector, date; EN 15340:2

46、007 (E) 10 b) specimen material; c) coating thickness; d) coating material; e) shear distance d; f) shear plate geometry according to ISO 1832; g) speed of shear plate; h) list of all single measurement results of the shear load resistances N including type of fracture: “Mode 1”: FSa (failure at int

47、erface between coating and substrate); “Mode 2”: FSa/c (mixed fracture, portion of the coating peeled off in area-%); “Mode 3a” / “Mode 3b”: FSc (failure within the spray deposit); i) arithmetic mean value and standard deviation of results; j) any particularities. EN 15340:2007 (E) 11 Annex A (infor

48、mative) Evaluation Depending upon the coating material and its adhesion to the substrate and cohesion between the splats, different modes of fracture can be distinguished. This can be seen from the load-displacement curves. Typical curves and sketches of crack configuration are shown schematically i

49、n Figures A.1 to A.5. Mode 1 coating adhesion coating cohesion Mode 3a coating disintegrates (crumbles) into small particles Key Y shear load N X displacement Figure A.3 Typical schematic load displacement curve and crack configuration during shear testing for Mode 3a failure of hard coatings EN 15340:2007 (E) 13 During shear testing of hard coatings continuous blistering of small or larger pieces of the coating may happen. Key Y shear load N X displacement 1 ductile b