The key to strong bonds between surfaces isn’t just in choosing the right adhesive; it’s also about preparing the surfaces. When you are trying to adhere metal to metal, it can be tricky. Here is our quick guide to surface preparation to help you out.
For smaller projects, you may be able to carry out abrasion with sandpaper or an emery cloth. If you are working at a larger scale, sandblasting or wire brushing might be more appropriate. The purpose of abrasion is to remove any dirt or oxide that has attached itself to the surface and might interfere with the bond. Mechanical blasting techniques are more effective than manual ones, but whichever technique is employed, it is important to follow on with degreasing to ensure that the surfaces are as clean as possible prior to applying the metal bonding adhesive.
Removing any traces of grease from the surface prior to bonding is important. The simplest way to do this is with an alcohol cleanser. There are several of these available, including ethanol, isopropyl alcohol, toluene and methyl alcohol. Before you choose your solvent, make sure that you have checked the safety information in case of reactions with the substrate. For more information on health and safety issues, visit the website of the Health & Safety Executive.
The surface may also need to be prepared with a chemical solution, which will alter the chemical structure of the metal to allow metal to metal adhesives such as http://www.ct1ltd.com/product-applications/metal-to-metal-adhesive/ to create a reliable bond. This usually involves making up a chemical bath with one or more substances and heating it to the required temperature. The metal should then be submerged in the bath for a set amount of time, between one and 30 minutes depending on the metal. Once the metal has been chemically treated, it requires rinsing and drying prior to the application of the adhesive.
These three steps can be used in combination to ensure that your metal surfaces are as well-prepared as possible before using the adhesive. If these steps are not carried out, it is possible that the adhesive will not be able to form a perfect bond, which could lead to product failure. To avoid future problems and enjoy the cost-saving benefits of metal bonding, always complete your preparation.