Bonding metal with adhesives can be a highly effective method when done correctly. The process involves preparing the surfaces of the adherend to ensure the best possible bond. This means not only removing oils, dirt, and waxes but also addressing the oxide that forms on the metal surface. When done properly, you can expect lap shear adhesion to exceed 1000 psi in most cases.
Proper Surface Preparation
For optimal results, it is crucial to follow thorough surface preparation guidelines. One useful resource is Hysol's surface preparation guide, which provides detailed instructions on how to clean and prepare surfaces for bonding.
Understanding Epoxy Types
Another common oversight is the assumption that all epoxies are the same. Epoxy adhesives available at marine or hardware stores for fiberglass laminating are not the same as true bonding adhesives. True bonding adhesives often contain an elastomer in their molecular structure, which enhances their toughness.
Favorite Metal Bonding Adhesives
Based on my experience, I have found three particularly effective metal bonding adhesives:
Lord Chemical Fusor T21 - This epoxy has a thixotropic viscosity like peanut butter, which prevents it from running on vertical surfaces. ProSet 175/276 and 176/276 - With a consistency similar to Vaseline and a butter-like spreading, these adhesives also feature thixotropic properties, making them ideal for vertical applications. Hysol E120HP - This adhesive has a viscosity like honey, though it is not thixotropic, which makes it prone to running on vertical surfaces.Conclusion
When it comes to bonding metal with adhesives, the key to success lies in proper surface preparation and selecting the right adhesive type. By following these guidelines and using the right adhesives, it is possible to achieve highly effective bonds that can exceed 1000 psi in lap shear strength.
For detailed surface preparation and product usage, be sure to consult reliable resources such as Hysol's surface preparation guide. Additionally, understanding the differences between various epoxy types and selecting the appropriate adhesive for the specific application will significantly enhance the effectiveness of the metal bonding process.
Keywords: metal bonding, adhesives, bonding adhesives