ASTM_B_839_-_04_2014.pdf

Designation:B83904(Reapproved 2014)Standard Test Method forResidual Embrittlement in Metallic Coated,ExternallyThreaded Articles,Fasteners,and Rod-Inclined WedgeMethod1This standard is issued under the fixed designation B839;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.INTRODUCTIONWhen atomic hydrogen enters steels and certain other alloys,it can cause loss of ductility or loadcarrying ability or cracking(usually as submicroscopic cracks),or catastrophic brittle failures atapplied stresses well below the yield strength or even the normal design strength for the alloys.Thisphenomenon often occurs in alloys that show no significant loss in ductility,when measured byconventional tensile tests,and is frequently referred to as hydrogen-induced delayed brittle failure,hydrogen stress cracking,or hydrogen embrittlement.The hydrogen can be introduced duringcleaning,pickling,phosphating,electroplating,autocatalytic processes,and in the service environmentas a result of cathodic protection reactions or corrosion reactions.Hydrogen can also be introducedduring fabrication,for example,during roll forming,machining,and drilling due to lubricantbreakdown as well as during welding or brazing operations.1.Scope1.1 This test method covers the determination of,on astatistical basis,the probability of the existence of hydrogenembrittlement or degradation in:1.1.1 A batch of barrel electroplated,autocatalytic plated,phosphated,or chemically processed threaded articles or fas-teners and1.1.2 A batch of rack plated threaded articles,fasteners,orrod.1.2 Industrial practice for threaded articles,fasteners,androd has evolved three graduated levels of test exposure toensure reduced risk of hydrogen embrittlement(see Section 3).These levels have evolved from commercial applicationshaving varying levels of criticality.In essence,they representthe confidence level that is required.They also represent thetime that finished goods are held before they can be shippedand used.This time equates to additional cost to the manufac-turer that may of necessity be added to the cost of the finishedgoods.1.3 This test method is applicable to threaded articles,fasteners,and rod made from steel with 1000 MPa(withcorresponding hardness values of 300 HV10 kgf,303 HB,or 31HRc)or surface hardened threaded articles,fasteners,or rod.1.4 This test method shall be carried out after hydrogenembrittlement relief heat treatment in accordance with therequirements of Guide B850.It may also be used for assessingdifferences in processing solutions,conditions,and techniques.This test method has two main functions:first,when used witha statistical sampling plan it can be used for lot acceptance orrejection,and second,it can be used as a control test todetermine the effectiveness of the various processing stepsincluding pre-and post-baking treatments to reduce the mobilehydrogen in the articles,fasteners,or rod.While this testmethod is capable of indicating those items that are embrittledto the extent defined in Section 3,it does not guaranteecomplete freedom from embrittlement.1.5 This test method does not relieve the processor fromimposing and monitoring suitable process control.1.6 This test method has been coordinated with ISO/DIS10587 and is technically equivalent.(WarningGreat careshould be taken when applying this test method.The heads ofembrittled articles,fasteners,or rod may suddenly break offand become flying projectiles capable of causing blindness orother serious injury.This hazard can occur as long as 200 hafter the test has started.Hence,shields or other apparatusshould be provided to avoid such injury.)NOTE1Test Method F1940 can be used as a process control and1This test method is under the jurisdiction ofASTM Committee B08 on Metallicand Inorganic Coatings and is the direct responsibility of Subcommittee B08.10 onTest Methods.Current edition approved May 1,2014.Published May 2014.Originallyapproved in 1994.Last previous edition approved in 2009 as B839 04(2009).DOI:10.1520/B0839-04R14.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 verification to prevent hydrogen embrittlement in fasteners covered by thistest method.NOTE2The use of inhibitors in acid pickling baths does notnecessarily guarantee avoidance of hydrogen embrittlement.1.7 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:2B602 Test Method for Attribute Sampling of Metallic andInorganic CoatingsB697 Guide for Selection of