Joining two or more components of metal together is a fundamental part of engineering. If you are associated with any manufacturing or processing industry, there’s a good chance that you will come across the need to join two metal components. There are several ways to go about it; however, welding and brazing are traditionally used to do so.

Most modern industries prefer using industrial adhesives for metal bonding. Using Adhesives over welding can vastly impact the final product. But the question remains, is adhesive bonding better than welding? That is the question we are going to answer in this blog! So if you are wondering if you should stick to traditional welding methods or switch to modern adhesive bonding, read this blog till the end to find out.

 

A] A Brief Overview Of Welding In Industrial Metal Bonding

Epoxy coating is a tough and durable material used to protect and enhance surfaces. The cross-linking between an epoxide resin and a polymine hardener is what gives epoxy coatings their strength and durability. They are resistant to chemicals, abrasion, and impact, and they have excellent adhesion to a variety of surfaces. Epoxy coatings are also resistant to UV radiation, which makes them ideal for outdoor applications.

However, there are several downsides to welding as well, which is leading many manufacturers to find alternatives. The permanent nature of the bond, the risk of damaging the material while welding, stress and distortion of the metal, and the overall safety concerns while welding are all reasons why industries are shifting towards adhesive bonding.

B] The Advantages Of Adhesive Over Welding For Industrial Metal Bonding

1. Adhesives Bond Dissimilar Materials

One factor that holds back welding from being the better choice for metal bonding is that it can only join two metal substrates. Whereas adhesive bonding can be used to bond metal with dissimilar materials, such as plastic, wood, and glass. Additionally, adhesives can bond materials that are difficult to bond, including oily metals and silicone rubber.

It was viable to use welding for every bonding requirement in the last century, as most structures were made of metal. However, in today’s industrial landscape, cheaper and lighter materials are preferred for the construction of automobiles, buildings, etc., which might not be able to withstand the high temperatures of welding.

2. Reduced Stress From Vibrations

Most industrial equipment faces vibrations during its lifetime. Vibrations can cause harm to the structural integrity of equipment by shaking the joints or altering the designs. Vibrations affect the entire welded surface which can lead to cracks and leaks in the metal sheets, causing safety risks.

Adhesives form a barrier between the two metal substrates that reduces the adverse effects of vibration on the metal. Industrial adhesives absorb vibrations making the final product more stable, safer and structurally sound. By absorbing the vibrations instead of amplifying them, adhesives contribute to the longevity of the machine.

3. Uniform Stress Distribution

One of the biggest benefits of metal bonding using adhesives is the uniform distribution of stress across the entire substrate surface. Uniform stress distribution eliminates unnecessary load on a single point on the substrate, making the bond more stable and safer.

Welding and even fasteners can cause stress concentrations by spot welding and drilling holes. Spot welding and ununiform stress distributions reduce the metal’s capability to bear the weight of the heavy equipment placed above it, becoming a safety hazard.

4. Next To None Added Weight

Being lightweight and flexible is one of the crucial adhesive bonding advantages for several industries. Adhesives are very lightweight in comparison to metal rivets and screws and welding. Welding and brazing often use additional metal to join two components, which increases the overall weight of the machine or structure.

The absence of such weld beads or reinforcements and the elimination of stress points offer better weight management solutions. Reduced weight of equipment increases their durability and reliability, which is always preferred.

5. No Risk Of Rusting

Rust is by far one of the most common reasons for structural failure. Rusted metal welding does not offer even half the strength and structural integrity of a healthy one. Welding can rust over time due to constant exposure to the sun, air, moisture, and other environmental elements. Rusted welding is a safety hazard and can cause huge losses in productivity and safety.

Adhesives are not only immune to rusting and corrosion but also act as a barrier between the environment and the metal. Adhesives can also be used as a barrier between a vulnerable metal substrate and a crucial part of the equipment. This barrier blocks the transmission of oxides that can potentially corrode valuable components.

6. Looks More Aesthetically Pleasing

Welding often leaves marks and bends in the metal, which may not always be aesthetically pleasing. The rough and mishappen metal at the point of welding is permanent and all the imperfections are visible to the end consumer.

Adhesives on the other hand are concealed between the substrates giving them a polished appearance. Adhesives significantly increase the aesthetic appeal of a structure. Engineers can leverage this to create beautiful structures and equipment without compromising safety or efficiency.

7. No Damage To The Structure

Structural adhesives can be applied on the edges of the substrates and set with the help of heat. The heat applied during the application and curing process is significantly lower as compared to welding. The process of joining metal using adhesives is non-invasive and does minimal damage to the structure.

Welding requires melting and reforming the metal using extreme temperatures. This can compromise the integrity of the metal and by extension the structure. This may not seem like much initially but this can go a long way. Adhesive bonding provides longevity and structural integrity, crucial for safety.

C] Industries Where Adhesives Can Perform Better Than Welding

• Automotive Industry: Automotive manufacturers are always looking to improve their vehicle designs. From aerodynamics to aesthetics, welding can never offer the flexibility that epoxy adhesives can. Plus, epoxy adhesives can be tailored to fit a wide array of requirements in the automotive industry, such as vibration reduction, electrical conductivity, and thermal resistance.
• Aerospace Industry: The problems and requirements of the Aerospace industry are quite similar to the automotive industry; however, there are some notable differences. Making the aircraft as much lighter as possible without compromising on safety is a key requirement of the industry. Adhesives are lighter and do not require any additional holes like rivets and screws.
• Construction Industry: As the construction industry evolves, engineers and architects are incorporating all sorts of materials for construction. Not all sorts of materials can be welded. Materials such as carbon fibre, ceramic, plastic, and plywood can only be bonded with metal using adhesives.

D] Adhesive vs. Welding: Factors to Consider When Choosing Between The Both

Adhesive bonding and welding are two of the most common and effective ways to bond metal substrates. However, it is often a topic of debate about which method is better than the other. Given that both methods have their advantages and disadvantages, it becomes difficult to choose between the two for a particular project.

It is often recommended to opt for welding if you require simple joining applications as it is cheaper than epoxy adhesives. However, if you need to bond metal with dissimilar materials, need lightweight & aesthetic alternatives, or require special properties from the bonding, adhesives are the right choice. It is best to find a reputed adhesive manufacturers in India to get your adhesive tailored according to your requirements.

Conclusion

Welding is a traditional means of joining bonding metal substrates. It is an inexpensive method to get high bond strength. Adhesive bonding is a modern method to bond metals and a lot of industries are already using it for their applications. Adhesive bonding offer a lot of advantages over conventional welding, making them a prime choice for metal bonding across various industries.

In some projects, you might even need to use both welding and adhesive bonding for the desired outcome. The mechanical, thermal, electrical, and chemical properties of epoxies are valuable for a lot of industrial applications which welding is not able to provide. If you have any queries about adhesives or are looking for custom epoxy adhesives for metal bonding, contact us today!