ASTM_F_1113_-_87_2011.pdf

Designation:F111387(Reapproved 2011)Standard Test Method forElectrochemical Measurement of Diffusible Hydrogen inSteels(Barnacle Electrode)1This standard is issued under the fixed designation F1113;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the procedure for measuringdiffusible hydrogen in steels by an electrochemical method.1.2 This test method is limited to carbon or alloy steels,excluding austenitic stainless steels.1.3 This test method is limited to flat specimens to whichthe cell can be attached(see 4.6 and 4.8).1.4 This test method describes testing on bare or plated steelafter the plate has been removed(see 4.4).1.5 This test method is limited to measurements at roomtemperature,20 to 25C(68 to 77F).1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2B183 Practice for Preparation of Low-Carbon Steel forElectroplatingB242 Guide for Preparation of High-Carbon Steel for Elec-troplatingB766 Specification for Electrodeposited Coatings of Cad-miumD1193 Specification for Reagent WaterF519 Test Method for Mechanical Hydrogen EmbrittlementEvaluation of Plating/Coating Processes and Service En-vironmentsG3 Practice for Conventions Applicable to ElectrochemicalMeasurements in Corrosion Testing3.Summary of Test Method3.1 A hydrogen-containing part is made the anode in anelectrochemical cell.The diffusible(atomic)hydrogen,whichcomes to the metal-electrolyte interface,is oxidized to protons(H+);H+combines with hydroxyl ions(OH)in the electrolyteto form water.The oxidation current is measured and related tothe hydrogen concentration.4.Significance and Use4.1 The critical level of hydrogen in steels is that hydrogenwhich can build up to high concentrations at points of hightriaxial stress causing embrittlement of the steel which can leadto catastrophic damage.This hydrogen can enter by variousmeans,such as during pickling and electroplating.Means ofreducing this hydrogen during processing are given in Speci-fication B766 and Practices B183 and B242.It is stillnecessary,however,to know how effective these methods are.Though the ultimate reason for measuring this hydrogen is torelate it to embrittlement,this is not within the scope of this testmethod.As susceptibility to hydrogen embrittlement is afunction of alloy type,heat treatment,intended use,and soforth,the tolerance for hydrogen must be determined by theuser according to Method F519.4.2 Though the actual hydrogen concentration is not deter-mined in this test method,the current densities have beenshown to be useful as an indication of relative hydrogenconcentrations(1-3),3and therefore the degree of hydrogenembrittlement(1,2).Thus,measurements can be compared toone another(see 4.1 and 7.1).4.3 This test method is applicable as a quality control toolfor processing(such as to monitor plating and baking)or tomeasure hydrogen uptake caused by corrosion.4.4 This test method is nondestructive;however,if there isa coating,it must be removed by a method which has beendemonstrated to neither damage the steel nor introduce hydro-gen to make the measurement.4.5 This test method is also applicable to situations produc-ing continuous hydrogen permeation,such as high pressure1This test method is under the jurisdiction of ASTM Committee F07 onAerospace and Aircraft and is the direct responsibility of Subcommittee F07.04 onHydrogen Embrittlement.Current edition approved Dec.1,2011.Published August 2012.Originallyapproved in 1987.Last previous edition approved in 2005 as F1113 87(2005).DOI:10.1520/F1113-87R11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Boldface numbers in parentheses refer to the list of references at the end of thisstandard.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 hydrogen cylinders or corrosion processes.The results,however,would require a different treatment and interpretation(4).4.6 This test method is also applicable to small parts,suchas fasteners.The technique,procedure,and interpretationwould,however,have to be altered.4.7 Use of this test method on austenitic stainless steels andother face centered cubic(FCC)alloys would require differentmeasurement times and interpretation of results because ofdiffering kinetics.4.8 This test method can be used on slig