Sheet Metal Adhesive Bonding

On a painted surface the adhesive is not bonding to the metal but instead to the paint coating.

Sheet metal adhesive bonding.

Structural adhesives an adhesive s heat resistance and chemical resistance are important considerations for metal bonding. These are used extensively to bond metal hinges knobs and fixtures to glass doors. Metal substrates and adhesives have widely different coefficients of thermal expansion cte which during repeated heating and cooling can cause the bonded joint to weaken. Technicians can save time by welding only where adhesive peel failure or ghost lines are a concern and achieve better results by bonding in areas where sheet metal can warp during the welding process.

Many epoxy metal glues require mixing adhesive and hardener components then applying with a specialized tool. Pieces to be glued must fit closely as these glues are poor gap fillers. Notice the heavy bead 1 4 inch of adhesive along the entire bare metal contact area for positive adhesion and rust protection. Follow the instructions on the packaging for amounts.

Open the product cap and apply metal glue to the prepared surface. Polyurethane glues are very sticky adhesives that will bond metal to metal as well as to a long list of other materials. These single part glues need moisture to set but are waterproof once cured. If coated before the adhesive is actually bonding to any coating rather than the steel itself which affects surface energy and how well the adhesive wets out.

One option is to mask the mating surfaces before coating preserving the metal surface. Ms polymer adhesive are ideal metal adhesives for thin sheets of metal such as truck panel bonding where the low shrinkage provides no read through you can t see where the adhesive is placed through the panel providing a good aesthetic finish. Nevertheless it s possible to achieve a successful bond to the metal or its surface coating depending on the bond strength you need. Super glues require about one drop per square inch of surface.

Steel surfaces are typically coated before or after bonding to prevent corrosion either with zinc galvanized steel or some type of paint.