ASTM E381-20 Standard Method of Macroetch Testing Steel Bars,Billets,Blooms, andForgings

Designation: E381-20 Standard Method of Macroetch Testing Steel Bars,Billets,Blooms, andForgings1 1. Scope= 1.1 Macroetching，which is the etching of specimens formacrostructural examination at low magnifications.is a fre-quently used technique for evaluating steel products such asbars,billets,blooams, and forgings. 1.2 Included in this method is a procedure for rating steelspecimens by a graded series of photographs showing theincidence of certain conditions. The method is limited inapplication to bars, billets,blooms, and forgings of carbon andlow alloy stecls. 1.3 A number of different etching reagents may be usedcepcnding upon the type of examination to be madc. Steelsreact differently to etching reagents because of variations inchemical composition. method of manufacture. heat treatmentand many other variables.Establishment of general standardsfor acceptance or rejection for all conditions is impractical assome conditions must be considered relative to the part inwhich it occurs. 1.4 This standard does nor purporr to adldress all of thesafety concerns.if any. associated wirh iss use. it is therespovsibility of the user of this standard to establish appro-priate sefety,healrha. cand ervirorutental practices and deter-erire the applicabiliry of regselatory limitcrions prior to use.Sce the specific precautionary statement in 5.3. 1.5 7his iuternacfional srendard was developed in accor-dance with inernctionally recognized principles ov standard-ization esicblishec in the Decisiow on Principles for theDevelopmen of Internacational Standards,Guides and Recomn-mewdcrions isseed by the World Trade Organization TechnicalBarriers ro Trade (TBTy Conanitiee. E381-20 Standard Method of Macroetch Testing Steel Bars,Billets,Blooms, andForgings