Volume 6 Design Guide for Bonding Metals - …

1 Volume 6 Design Guide for Bonding MetalsGlobal Distributor of Henkel LOCTITE(800) 888-0698 LOCTITE Design Guide for Bonding Metals , Volume 6 | 1 ContentsSection 1 Why Bond Metals with LOCTITE Brand Adhesives? ..2 Section 2 How to Use this Guide ..3 Performance Characteristics ..3 Section 3 adhesive Joint Design ..4 Section 4 Factors Affecting Activator Selection ..7 Introduction ..7 Activators and Primers ..8 Fixture Time Matrix ..9 Performance Matrix ..10 Solventless vs . Solvent-borne Activators ..11 Section 5 Heat Cure Parameters for Two-Step Acrylic Adhesives.

2 13 Section 6 adhesive Review ..14 Acrylics, Two-Step ..14 Acrylics, Two-Part ..15 Cyanoacrylates ..16 Epoxies ..17 Hot Melts ..18 Polyurethanes ..19 Elastomers ..20 Section 7 metal Bonding Chapters ..21 How to Use the adhesive Sheer Strength Tables .. 21 Induced Gap ..22 Aluminum ..23 Anodized Aluminum ..26 Copper ..28 Nickel ..30 Stainless Steel ..32 Steel ..34 Zinc Dichromated Steel ..38 Galvanized Steel (Zinc) ..40 Section 8 Functional Coatings (Surface Treatment) ..42 Alkaline Cleaners ..42 Acid Cleaners ..42 Zinc Phosphate Process ..43 Conditioners for Zinc Phosphate.

3 43 Zinc Phosphate ..44 Iron Phosphate Process ..44 Non-Phosphate/Nanoceramic Technology ..45 Aluminum Conversion Coating Processes ..46 Light Metals ..46 Section 9 Test Methodology ..48 Substrate Preparation ..48 Cure Conditions ..48 Test Methods ..49 Disclaimer ..502 | The LOCTITE Design Guide for Bonding Metals , Volume 6 The LOCTITE Design Guide for Bonding Metals , Volume 6 | 3 LOCTITE AdhesiveOverlap Weld1/4" Nut & BoltPop RivetsDouble-sided Tape050010001500200025003500400045003000 Shear Stress (lbf)$ $ $ $ $ of LOCTITE Structural Adhesives vs.

4 Mechanical Fasteners: Adhesives distribute stress evenly across the bond linewhile mechanical fasteners create stress concentrationpoints which lead to premature failure . Improved aesthetics of the final assembly no boltheads sticking out . Adhesives minimize or eliminate secondaryoperations like punching holes required with manyfastener applications .Section 1 Why Bond Metals with LOCTITE Brand Adhesives?Advantages of LOCTITE Structural Adhesives vs . Welding, Brazing, and Other Thermal Joining Methods: Allow joining of dissimilar substrates . Thermal joining methods can cause distortion of thepart, which may affect the assembly s performance.

5 Adhesives do not distort parts . Improved aesthetics of the final assembly no visibleweld seams or discoloration . Adhesives minimize or eliminate secondary operationslike grinding and polishing .Visit and click on Bonds vs. Bolts to see video proof of bonds outperforming bolts, rivets, and spot Structural Adhesives are nearly as strong as overlap Structural Adhesives withstand the test of time better than spot welds and .Selecting the proper adhesive for an application demands a consideration of the processing and performance characteristics of the adhesive .

6 This Guide has been designed to provide this information in a format that will allow the end-user to rapidly identify the best adhesive option for evaluation in their application .PERFORMANCE CHARACTERISTICSWhen selecting an adhesive for an application, it is important to consider whether the adhesive s processing characteristics will be compatible with the assembly production process . The processing characteristics of greatest interest to the end-user typically revolve around the dispensing and curing properties of the adhesive . Information about these characteristics is important because it will help the end-user answer questions such as: What types of dispensing equipment will be requiredfor the adhesive ?

7 Is the adhesive easily dispensedusing automated or manual methods? Will special curing equipment, such as ovens or UVlight sources, be required? How will environmental factors, such as relativehumidity, affect the curing rate of the adhesive ? How long will it take the adhesive to develop sufficientstrength for the assembly to proceed to the next stepin the assembly process? Will racking of parts during cure be required? Willspecial fixtures be needed to hold the assembly whilethe adhesive is curing? How much floor space will berequired for the racked parts?

8 To gain an understanding of the processing characteristics of the adhesives in this Guide see: Section 3: adhesive Joint Design explains thebasic terms and concepts relating to joint Design ,including a discussion of types of joints, commonstresses associated with joints, and managing stressdistribution using key Design guidelines and best practices . Section 4: Factors Affecting Activator Selectionprovides detailed information on the effect that activatorselection has on the processing and performancecharacteristics of two-step acrylic products . Section 5: Heat Cure Parameters for Two-Step AcrylicAdhesives provides information on the times andtemperatures needed to heat cure these products whenan activator cannot be used.

9 Section 6: adhesive Review provides an overview ofthe dispensing and curing characteristics of each familyof adhesives . Section 7: metal Bonding Chapters provides detailedshear strength data for the adhesives evaluated in thisguide on aluminum, anodized aluminum, stainlesssteel, steel, zinc dichromated steel, zinc galvanizedsteel, nickel plated steel, and copper . Bond strengthsare evaluated at ambient conditions and after exposureto high temperatures as well as high humidity andcorrosive environments . For aluminum, steel, stainlesssteel and copper, the effect of surface roughening onbond strength is also evaluated.

10 Section 8: Functional Coatings (Surface Treatment)provides a basic overview of cleaning and pre-treatmentoptions for preparing Metals for painting or additionalprocessing steps . Topics covered include alkaline andacid cleaners/pickles, zinc and iron phosphate processconversion coatings, non-phosphate/nanoceramictechnology, and aluminum conversion coatings . Section 9: Test Methodology includes an overviewof metal coupon/substrate preparation, defines cureconditions by adhesive type and chemistry, and explainsthe various tests used to generate data for this Guide .