You can join two substrates in a few different ways. One option is a permanent joining, such as through welding or fasteners. Another is using adhesive, which connects two surface areas. Often the surfaces have unique qualities, so you need to evaluate their conditions to find the optimal adhesive. 

If you're considering tape, you should look at a variety of factors impacting the surface, including: 

•Roughness or smoothness

•Coating

•Flexibility

•Cleanliness

•Size

•Surface energy

The importance of surface energy

You may think of surfaces as immovable and immobile, but they actually have measurable energy. Surface energy refers to the energy it takes to increase the surface's size. The higher the surface energy, the greater the adhesion effectiveness. 

An adhesive must "wet out" to achieve a strong bond. That means the adhesive has to flow to increase the contact area and improve the attractive forces between the adhesive and the bonding surface. For instance, lower-energy surfaces can wet out higher-energy surfaces. You can measure wetting through the contact angle of the liquid on the surface. 

Examples of High Surface Energy Surfaces

When searching for the right tape for your substrates, keep in mind that that the higher the surface energy, the better the adhesion. Glass and metals demonstrate the highest surface energy. A few other substances with high surface energy include: 

•Tin, aluminum, zinc and copper

•Acrylic and epoxy paint

•Lead and stainless steel

•Polycarbonate

•Glass

•Porcelain

Examples of low surface energy substrates

Low surface energy adhesives are specially formulated to address the substrate's makeup because they tend to bond less effectively with tape. A substance can change the energy level of an object. The unwaxed hood of a car is high energy, but a waxed hood is low energy and won't "wet out." Other examples of substrates with low energy surfaces include: 

•Powder-coated paint 

•Acetal

•Polyethylene, polystyrene and polypropylene 

•EVA and PVA

 

You can find low surface energy adhesives, which are made to adhere with maximal wetting, among tesa's inventory. Our choices include acrylic core and ACX^plus. 

What else will help form a good adhesive bond? 

Adhesive bonds depend on more than just surface energy, of course. Unless you use a flexible base material, you need to ensure your substrate is clean, dry and flat. You can remove debris and dirt from a surface or use abrasion to help it bond. Your surface should also be at the right temperature. Hot surfaces will turn tape gummy, and cold ones can make it hard for the tape to stick. 

Find the right tape for your surface

Substrates and adhesion can be tricky if you lack the correct information. You can share your application with tesa's tape experts and receive assistance in identifying the best tape for your surface. Contact us today to schedule a consultation and discover the best product for your needs.