EN ISO 8407-2014 en Corrosion of metals and alloys - Removal of corrosion products from corrosion test specimens《金属和合金的腐蚀 腐蚀试样上腐蚀产物的清除(ISO 8407 2009)》.pdf

1、ICS77.060NOCOPYINGWITHOUTBSIPERMISSIONEXCEPTASPERMITTEDBYCOPYRIGHTLAWBRITISHSTANDARDCorrosionofmetalsandalloysRemovalofcorrosionproductsfromcorrosiontestspecimensBS EN ISO 8407:2014National forewordThis British Standard is the UK implementation of EN ISO 8407:2014. It is identical to ISO 8407:2009.

2、It supersedes BS ISO 8407:2009 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee ISE/NFE/8, Corrosion of metals and alloys.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport

3、 to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.BS EN ISO 8407:2014This British Standardwas published underthe authority of theStandards Policy andStrategy Commi

4、ttee on 30November 2009Amendments/corrigenda issued since publicationDate Comments 30 April 2014 This corrigendum renumbers BS ISO 8407:2009 as BS EN ISO 8407:2014ISBN 978 0 580 82057 1 The British Standards Institution 2014. Published by BSI Standards Limited 2014EUROPEAN STANDARD NORME EUROPENNE E

5、UROPISCHE NORM EN ISO 8407 March 2014 ICS 77.060 English Version Corrosion of metals and alloys - Removal of corrosion products from corrosion test specimens (ISO 8407:2009) Corrosion des mtaux et alliages - limination des produits de corrosion sur les prouvettes dessai de corrosion (ISO 8407:2009)

6、Korrosion von Metallen und Legierungen - Entfernen von Korrosionsprodukten von Korrosionsprobekrpern (ISO 8407:2009) This European Standard was approved by CEN on 9 February 2014. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this

7、 European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical 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 ve

8、rsions (English, French, German). A version in any other language made by translation under the responsibility 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 Austri

9、a, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden,

10、 Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION 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 n

11、ational Members. Ref. No. EN ISO 8407:2014 Eii ISO 2009 All rights reservedForeword The text of ISO 8407:2009 has been prepared by Technical Committee ISO/TC 156 “Corrosion of metals and alloys” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 8407:2014 b

12、y Technical Committee CEN/TC 262 “Metallic and other inorganic coatings” the secretariat 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 September 2014, and conflicting na

13、tional standards shall be withdrawn at the latest by September 2014. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the

14、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

15、gary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 8407:2009 has been approved by CEN as EN ISO 8407:2014 without any mo

16、dification. BS EN ISO 8407:2014 8407:2014 (E)EN ISO INTERNATIONAL STANDA RD ISO 2009 All rights reserved 1Corrosion of metals and alloys Removal of corrosion products from corrosion test specimens WARNING Safety rules for personnel: handling of the solutions used for removal of corrosionproducts mus

17、t be left to skilled personnel or conducted under their control. The equipment mustbeused and maintained by skilled personnel, not only so that the procedures can be performed correctly, but also because of the hazards to health and safety that are involved. 1 Scope This International Standard speci

18、fies procedures for the removal of corrosion products formed on metal andalloy corrosion test speci mens during their exposure in corros ive environments. For the purpos e of thisInternational Standard, the term “metals” refers to pure metals and alloys. The specified proceduresare designed to remov

19、e all corrosion products without significant removal of base metal. This allows an accurate determination of the mass loss of the metal, which occurred during exposure tothe corrosive environment.These procedures may, in some cases, also be applied to metal coatings. However, possible effectsfrom th

20、e substrate must be considered. 2 Procedures2.1 General 2.1.1 A light mechanical cleaning treatment by brushingwith a soft bristle brush under running water should first be applied to remove lightlyadherent or bulky corrosion products. 2.1.2 If the treatment described in 2.1.1 does not remove all co

21、rrosion products, it willbe necessary to use other procedures. These are of three types:a) chemical; b) electrolytic; c) more vigorous mechanical treatments.NOTE These treatments will also remove some base metal. Whichever method is used, it might be necessary to repeat the cleaning treatment to ens

22、ure completeremoval of the corrosion products. Removal shall be confirmed by visual examination. The use of a low-powermicroscope (i.e. 7 to 30) is particularly helpful with a pitted surface since corrosion products may accumulate in pits. 2.1.3 An ideal procedure should remove corrosion products an

23、d not result in removal of any base metal. Two procedures can be used to confirm this point. One procedure uses a control specimen (2.1.3.1) and theother requires a certain number ofcleaning cycles onthe corroded specimen (2.1.3.2).BS EN ISO 8407:2014 ISO 8407:2009 (E)2 ISO 2009 All rights reserved2

24、.1.3.1 Uncorroded control specimens, which s hould be similar chemically, metallurgically, andgeometrically to the test specimens, should be cleaned by the same procedure as used for the test specimen. By weighing the control specimen before and after cleaning (weighing to the fifth significant figu

25、re issuggested, e.g. a 70 g specimen should be weighed to three decimal places), the metal loss resulting from cleaning may be determined. The mas s loss of the control specimen will reflect the mass loss of testspecimens resulting from the cleaning procedure. 2.1.3.2 The cleaning of each corroded t

26、est specimen should be repeated several times after the removalof the corrosion productsis completed. The mass shall be plotted as a function of the number of equal cleaning cycles (see Figure1). Point A represents the mass of corroded specimens before the start of thecleaning. In many cases two str

27、aight lines, AB and BC, will be obtained. Line AB characterizes the removal ofcorrosion products and maynot always be visible. Line BC characterizes the removal of substrate after thecorrosion products are gone. Point D, which characterizes the mass of the pure metal at zeronumber of cleaning cycles

28、, is obtained by ex trapolation of line BC to the ordinate axis. In some cases, the relation m ay not be linear and the most appropriate extrapolation shall then be made. If no intervals of equal cleaning cycles are used during one cleaning procedure, the x-axis should beexpressed in time units. Key

29、X numbers of cleaning cycles or time units Y massFigure 1 Mass of corroded specimensafter repetitive cleaning cycles2.1.3.3 The true mass of the specimen, after removal of the corrosion products, will be a value betweenthe masses representedbythe points B and D, depending on the degree ofprotection

30、furnished bythecorrosion products during the cleaning procedure. 2.1.4 The preferred cleaning method will be that which a) provides efficient removal of corrosion products, b) provides loworzero mass loss when applied to new uncorroded specimens (see 2.1.3.1), and c) provides a curve of mass as a fu

31、nction of the number of cleaning cycles or time of pickling, which is close to horizontalwhen the latter is plotted as the abscissa (see 2.1.3.2). 2.1.5 When chemical or electrolytic procedures are used, solutions freshly prepared with distilled ordeionized water and reagent grade chemicals shall be

32、 used. 2.1.6 After cleaning, the specimen should be thoroughly rinsed with tap water,a light brushing during thisprocedure will help to remove any remaining surface products resulting from the cleaning process. Finally, theBS EN ISO 8407:2014 ISO 8407:2009 (E) ISO 2009 All rights reserved 3specimens

33、 shall be rinsed with distilled or deionized water. The specimen shall then be r insed thoroughly inethanol and dried using a hot air blower or an oven. After that, the specimens shall be allowed to cool in a dessicator to the balance room temperature before weighing.2.2 Chemical procedures 2.2.1 Ch

34、emical procedures involve immersion of the corrosion test specimen in a chemical s olution which is specifically designed to remove the corrosion products with minimal dissolution of anybase metal. Several procedures are listed in Annex A (see Table A.1). To facilitate the cleaning, it is strongly r

35、ecommended to use an ultrasonic bath treatment. 2.2.2 Chemical cleaning is often preceded by light brushing of the test specimen to remove lightly adherent, bulky corrosion products. 2.2.3 Before the chemical treatment, clean the specimens as described in 2.1.1. In connectionwith theintermittent rem

36、oval of specimens for weighing, brush the specimens, if necessary, to facilitate the removal oftightly adherent corrosion products. 2.3 Electrolytic proceduresElectrolytic cleaning can also be used to remove corrosion products. Several methods of electrolytic cleaningof corrosion test specimens are

37、given in Annex A (see Table A.2). To facilitate the cleaning, it is stronglyrecommended to use an ultrasonic bath treatment. Electrolytic cleaning should be preceded by light brushing of the test specimen to remove lightly adherent,bulky corrosion products. Brushing should also follow electrolytic c

38、leaning to remove anyloose slime ordeposits. This will help to minimize any redeposition of metal fro mreducible corrosion products, which wouldreduce the mass loss.2.4 MechanicalproceduresMechanical procedures can include scraping, scrubbing, brushing, ultrasonic me thods, mechanical shock and impa

39、ct blasting (grit blasting, water-jet blasting, etc.). These methods are often used to remove heavilyencrusted corrosion products. Scrubbing with a bristle brush and a mild abrasive/distilled water slurry can alsobe used to remove corrosion products. Vigorous mechanical cleaning will result in the r

40、emoval of some base metal, so care should be exercised.These methods should be used only when others fail to provide adequate removal of corrosion products. As with the other methods, correction formetal loss due to the cleaning method is recommended. Themechanical forces used in cleaning shall be m

41、aintained as constant as possible. 3 Test reportThe test report shall include the following information:a) a reference to this International Standard; b) the procedure used to remove corrosion products; c) for chemical procedures, the composition and concentration of the chemicals employed or the de

42、signation according to Table A.1, the solution temperature and the duration of each cleaning cycle ornumber of equal cleaning cycles; d) for electrolytic procedures, the composition and concentration of chemicals employed or the designation according to Table A.2, the solution temperature, the anode

43、 material and current density, and the duration of cleaning; BS EN ISO 8407:2014 ISO 8407:2009 (E)4 ISO 2009 All rights reservede) formechanical procedures, the specific mechanical method employed (bristle-brush scrubbing, wooden scraper, etc.), abrasive compounds used, and the duration of cleaning;

44、 f) where multiple procedures are used, the appropriate details for each method and the sequence of methods; g) the results of control clea ning (see 2.1.3.1) or from repetitiv e cleaning cycles (see 2.1.3.2) designed toassess mass lossfrom the removal of base metal during the cleaning process;h) th

45、e mass loss due to corrosion (see 2.1.3.3). BS EN ISO 8407:2014 ISO 8407:2009 (E) ISO 2009 All rights reserved 5Annex A(informative) Chemical and electrolytic cleaning procedures for removal of corrosion products A.1 General In the development of this International Standard, a number ofsources were

46、consulted to identify chemical and electrolytic cleaning procedures. This annex summarizes the results of this survey. Prior to adopting these cleaning procedures, the user should conduct a test on control samples to ensure theefficiency of the chosen method. A.2 ProceduresTables A.1 and A.2 summari

47、ze various chemical and electrolytic cleaning procedures for removal of corrosion products. The specific choiceof procedure for a given materialwilldepend on many factors, including previous experience. If more thanone chemical or electrolytic cleaningprocedure isgiven for a metal, the procedures ar

48、e usually listed in preferred order. This International Standard should be consulted for guidancein the proper application of the procedures in Tables A.1 and A.2. For all the cleaning procedures listed, it is recommended that the surfaces should be maintained vertical during cleaning. This will min

49、imize retention of any gases released during the cleaning procedure. The times specified represent recommendations appropriate for mass-loss s tudies in the context of Figure 1. However,when the cleaning procedure is adopted for other purposes (e.g. cleaning of fracture surfaces forinspection, using a microscope), the exposure timemay be longer. WARNING When working with dangerous substances (such as cyanide, chromium trioxide, zincdust), all necessary safety precautions shall be taken.Table A.1 Chemical cleaning procedures for removal of co