ASTM_D_2651_-_01_2008.pdf

Designation:D265101(Reapproved 2008)Standard Guide forPreparation of Metal Surfaces for Adhesive Bonding1This standard is issued under the fixed designation D2651;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.This standard has been approved for use by agencies of the Department of Defense.INTRODUCTIONIt is impossible and impractical to present a single surface-preparation method for a metal group,such as aluminum alloys,stainless steels,magnesium alloys,etc.The wide variety of individual alloysand heat treatments under each group,the fact that certain adhesives exhibit specific compatibilitieswith surface preparation and the complexity and nature of parts being bonded preclude the use of anall-inclusive procedure for a metal group.Procedures for aluminum alloys are well standardized,possibly because more bonding has been done with these alloys.Preliminary tests should be conductedwith the specific adhesive and the exact lot of metals to determine performance.This is especially truefor stainless steel.The adhesive manufacturers recommendation should also be considered.1.Scope1.1 This guide covers procedures that have proved satisfac-tory for preparing various wrought metal surfaces for adhesivebonding.It does not address the preparation of cast metals.1.2 Surface preparation methods are included for:MetalSectionAluminum Alloys7Stainless Steel8Carbon Steel9Titanium Alloys10Magnesium AlloysCopper and Copper Alloys11121.3 Procedures included herein are based on the commercialpractice of numerous agencies and organizations.The methodsmay be revised or supplemented,as necessary,to includemethods based on proven performance.1.4 The surface preparation of metal systems used forqualification and quality control testing of the adhesive shouldbe agreed upon by both manufacturer and user.1.5 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.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:2D907 Terminology of AdhesivesD1125 Test Methods for Electrical Conductivity and Resis-tivity of WaterD2674 Methods of Analysis of Sulfochromate Etch SolutionUsed in Surface Preparation of AluminumD3933 Guide for Preparation of Aluminum Surfaces forStructural Adhesives Bonding(Phosphoric Acid Anodiz-ing)2.2 ASM International Document:3Metals Handbook Volume V2.3 Military Specifications:4MIL-A-8625 Type II,Anodic Coatings for Aluminum andAluminum AlloysMIL-M-3171 Magnesium Alloy,Processes for Pretreatmentand Prevention of CorrosionMIL-M-45202 Magnesium Alloy,Anodic Treatment of1This guide is under the jurisdiction ofASTM Committee D14 on Adhesives andis the direct responsibility of Subcommittee D14.80 on Metal Bonding Adhesives.Current edition approved April 1,2008.Published April 2008.Originallyapproved in 1967.Last previous edition approved in 2001 as D2651 01.DOI:10.1520/D2651-01R08.2For 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.3Available from American Society of Metals(ASM International),9639 Kins-man Rd.,Materials Park,OH 44073-0002,http:/www.asminternational.org.4Available from Standardization Documents Order Desk,DODSSP,Bldg.4,SectionD,700RobbinsAve.,Philadelphia,PA19111-5098,http:/www.dodssp.daps.mil.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 2.4 SAE Standards:5Aerospace Material Specification 2470 E Anodic Treatmentof Aluminum Base Alloy,Chromic Acid Treatment3.Terminology3.1 DefinitionsMany of the terms in this guide are definedin Terminology D907.4.Apparatus4.1 Trays or Pans,suitable for preparation of laboratoryspecimens and small parts.Generally in production,a series oftanks containing the necessary solutions is arranged withoverhead cranes to transport parts to be prepared.Tanks shouldbe lined with suitable materials to resist the solutions,andmethods for circulating the solutions and heating with tempera-ture controls should be included if required.4.2 Hooks,Baskets,Clamps,or other holding devices,maybe used to convey parts being prepared.The use of a 300 Seriesstainless steel for such equipment is suggested.Other metalsmay be used if they are resistant to the solution used.5.Conditions5.1 HandlingAll parts during and after processing andbefore bonding should be handled as little as possibl