Metal substrates and their bonding methods

There are many ways in which metal substrates can be fixed and bonded together, from adhesive bonding to metal fasteners and thermal joining. Here is a look at the most common forms.

Thermal Joining

This can entail brazing, soldering and welding, which only work on metals that are homogeneous with close melting points. The problem with thermal joining is that it can result in discolouration and distortion, warping the metal and damaging the alloy.

Mechanical Fasteners

Fasteners are easy to use and can connect different metal substrates. They can also be easily removed. However, with mechanical fasteners, you need to drill holes into the metal that will be connected, which can change the design and damage the metal substrates.

Shrink Fitting and Press Fitting

This method functions by heating a hole within the metal so it expands. Once it’s expanded, another piece from an additional substrate is fitted into the hole under pressure. When the hole cools, it contracts to form a very tight connection and seal.

Press fitting doesn’t use thermal energy like shrink fitting. Instead, it uses high pressure to connect metal substrates. Although press fitting requires less energy, the bond between the metals is weaker.

Metal Fasteners

These come in two types: permanent fasteners and releasable fasteners. Bolts and screws with rivets and clamps make up the first kind, while the latter is made up of clamps and couplers, which are quick-release. Metal fasteners need to be strong because they have to support a lot of weight, so they are often made of iron or titanium.

Adhesives

According to https://www.sciencedirect.com/topics/materials-science/adhesive-bonding), adhesive bonding is a process whereby two or more parts are joined together through the solidification of a non-metallic adhesive material. Bonding through the use of adhesives involves epoxies, glues and plastics. Metal bonding adhesive like those found at http://www.ct1ltd.com/product-applications/metal-to-metal-adhesive/,
such as super-glues, can bond metal substrates with a potency that is close to the strength of the substrates themselves.

The advantages of adhesives are that they are more resistant to stress than other methods of bonding. In addition to creating a bond, they also create a seal that prevents joints between metal substrates from corroding. You can also use adhesives to join two metals with irregular surfaces as well as two completely different metal substrates with different melting points.