ASTM_D_2094_-_00_2014.pdf

Designation:D209400(Reapproved 2014)Standard Practice forPreparation of Bar and Rod Specimens for Adhesion Tests1This standard is issued under the fixed designation D2094;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 practice describes bar-and rod-type butt-joinedadhesion test specimens and procedures for preparing andbonding them.The specimens are intended to be used withvarious adherend materials in like or unlike combinations fordetermining the strength properties of adhesives in accordancewith Test Method D2095.1.2 The values stated in SI units are considered to be thestandard.The values in parentheses are for information only.1.3 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:2D907 Terminology of AdhesivesD2093 Practice for Preparation of Surfaces of Plastics Priorto Adhesive BondingD2095 Test Method for Tensile Strength of Adhesives byMeans of Bar and Rod SpecimensD2651 Guide for Preparation of Metal Surfaces forAdhesiveBonding2.2 ASTM Adjuncts:Alignment Fixture Drawings33.Terminology3.1 DefinitionsMany terms in this practice are defined inTerminology D907.4.Significance and Use4.1 The procedures outlined in this practice are designed tostandardize the test specimens,surface preparations,combina-tions of materials,and adhesive selection.Because of theflexibility in the procedure,it is important to have some idea ofthe kind of properties that will be observed during testing.5.Test Specimens5.1 GeometryTest specimens conform to the forms anddimensions shown in Fig.1,Fig.2,or Fig.3.Only the barspecimen(Fig.1)shall be used for cleavage strength tests.Only the rod specimen(Fig.2)or the modified bar specimen(Fig.3)shall be used for tests in torsional shear.Amodificationof the specimen is permissible in tensile tests with dissimilaradherends,particularly if one of the adherend materials isdifficult to machine(for example,glass)or if the strength of theadherend is such that failure under stress occurs at the drilledhole.This modification consists of a sheet of the materialapproximately 19 mm(34in.)square and 112to 6 mm(116to14in.)thick inserted and bonded between the ends of the bar orrod specimens.For comparison purposes,specimen geometryshall be the same unless the effect of insert dimensions is understudy.5.2 Machining of Adherends:5.2.1 Use metal adherends machined from bar or rod stockwith the surface to be bonded finished to 1 m.5.2.2 Machine plastic from laminated flat panels using adiamond charged wheel for rough machining and a carbide-tipped tool for finish machining.Do all machining dry usingcare not to damage surfaces by overheating or contaminationwith lubricants.Machine laminar materials so that the axis ofthe specimen will lie in the plane of the lamina,and so that theplane of the lamina coincides with one side of the specimenwith the hole perpendicular to the plane of the lamina.Finishplastic to 80 m or better unless studying surface finish.5.2.3 Nonreinforced plastics(either thermoplastic or ther-mosetting)molded in a 127 by 12.7 by 12.7-mm(5 by 0.5 by0.5-in.)bar mold,machined to a 38.1 mm(1.5 in.)length anda hole drilled as shown in Fig.1.Specimens machined fromextruded,cast,or molded plastic rod or sheet are also accept-able.5.3 Surface Preparation of Adherends:1This practice is under the jurisdiction of ASTM Committee D14 on Adhesivesand is the direct responsibility of Subcommittee D14.80 on Metal BondingAdhesives.Current edition approved March 1,2014.Published March 2014.Originallyapproved in 1962.Last previous edition approved in 2006 as D2094 00(2006).DOI:10.1520/D2094-00R14.2For 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.3Detailed working drawings of the fixtures shown in Fig.4 and Fig.5 and theirparts are available from ASTM International Headquarters.Order Adjunct No.ADJD2094.Original adjunct produced in 1966.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.3.1 Prepare specimen surfaces in accordance with recom-mendations of the adhesive manufacturer,unless it is desired toevaluate other methods of preparation,or,unless in the case ofspecific surfaces,other methods are considered superior(seeGuide D2651).5.3.2 The minimum acceptable method for preparation ofmetallic adherend surfaces,instead of a chemical treatment