Inspired by an article described in the 6th edition of the S&D specialist (26-03-2021). In this blog we explain the various advantages of adhesive bonding compared to welding.
“Did you know that airplanes are, for the most part, glued?”
Why Glue and not Weld?
From the construction of the first aircraft, gluing techniques have been used. Weight is saved by implementing glue joints, originally this was also the reason to replace welding with gluing. Welding requires a minimum thickness in order to be implemented, which may cause limitations. Gluing does not
have this limitation, as even the thinnest material can be glued.
Adhesives are rare in metal assembly, but why?
The main reason is that there is often an assumption that adhesive joints are weaker than other joints.In fact, a good adhesive bond often turns out to be even stronger than a comparable weld.As Paul Hartgers named in the 6th edition of Q&A specialist: “In our youth we often ‘glued’ with the white paper glue or the white markers. And because that was never done very well, these glue joints were often bad. That stuck.”
Welding
Welding is a technique that is actually standard in the metal industry. Nevertheless, there are quite a few disadvantages associated with this welding, such as;
- Welding changes material properties to often worse in and around the weld.
- Loose defects are often indispensable when welding
Sheet metal must have a minimum thickness in order to be welded.
In some situations, metal deformations can be resolved by “‘narichten”.
Advantages Adhesive bonding?
“A good glue joint (well designed and well made) is always stronger than the best weld laid.” – Paul Hartgers
In the aircraft industry aircraft industry the first adhesive bonding was used with the Fokker in 1954, still these first models are still being flown. How durable do you want it to be? Advantages over gluing are:
First of all, the adhesive compared to the weld does not change the material properties at all. This allows the strength of the material to be maintained.This is especially important for the metal industry since high strength steels above 250 degrees lose this high strength, which could be prevented with adhesives.
Second, the use of adhesive bonding allows the material to follow the intended stress lines for joining. This prevents the creation of stress peaks around the joint.
In addition, welding often involves a lot of heat in the application process; adhesives do not. This eliminates the need to counteract shrinkage stresses.
Critical aspect of adhesives
Lijm Partner believes that in many cases adhesives are a perfect alternative to other joining methods such as welding, but we do not lose sight of reality. In fact, adhesives also have two potential critical caveats, namely;
First, grease-free working is important when using adhesives, unfortunately, grease is sometimes present in metal processing. This is because of corrosion protection and presents a challenge.
In addition, execution at all times determines the strength of the bond. For this, however, Non-Destructive Testing (NDT) techniques are also available to set the adhesive bond without damage.
Lijm Partner & Metal Adhesives
The metal industry metal industry is always looking for innovation. Glue Partner can help you do just that.
Nowadays it is no problem to bond metal parts with materials such as plastic or rubber. There is a wide range of industrial adhesives available that are ideally suited for the assembly of complicated products, for example in securing and sealing. With more than 30 years of experience in this field, Glue Partner is a solid partner when it comes to such industrial adhesive applications. Our product range includes a wide range of high-quality products. We attach great importance to the reliability of bonding, even under extreme conditions.
Want to know more? Then check out our website (www.lijmpartnershop.nl) or contact us at (+31)85 273 30 43 or info info@lijmpartner.nl.
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