This also applies to the vehicle manufacturing segment of the transportation industry. Bonding the most diverse range of metal substrates is common practice and bonding is often preferred over conventional joining technologies.
What kind of metals are used in the vehicle manufacturing sector?
Different types of metals are used in the vehicle manufacturing sector, such as treated steels, untreated steels, and stainless steel and aluminium structures. Stainless steel is used in the bodywork and vehicle manufacturing industry because of its high stability in multiple areas. Aluminium, of various qualities, is indispensable in the industry for achieving weight reduction. These different metals are attached to each other or to other materials. Bonding a window to the metal chassis of a bus or fixing a sandwich panel inside an aluminium profile are examples.
Load-bearing elements are mostly made of steel in vehicle construction. Stainless steel is used because of its high corrosion resistance. To achieve weight reduction, aluminium, in various grades of quality, has become indispensable in body and vehicle construction.
If you would like additional information about using Sabatack® to bond metals in the transportation industry, download the free brochure here. The brochure contains a comprehensive overview of our adhesives and sealants, their commonly occurring applications and key benefits.
Bonding or welding metals: these are the four main advantages of bonding over welding or mechanical fixation
- Uniform stress distribution
When an adhesive is used to bond metal, the tension is uniformly distributed across the connection. This is in contrast to other joining techniques, in which the tension is concentrated at the connecting points. This peak tension creates a local load and a less durable bond.
- Efficient
The adhesive to metal application process is faster than the connection process of other joining techniques, such as using screws or welding. Furthermore, in many cases adhesives are suitable for bonding, as well as for sealing seams, joints and overlaps. This therefore eliminates an extra sealing step.
- Aesthetic benefits
Bonding metals also yields benefits in terms of the vehicle's appearance. This is because the bond is invisible in the exterior. MS polymer adhesives adhere to virtually any surface, which results in a large freedom of choice of materials. Furthermore, elastic MS polymer adhesives are easy to paint over and provide for a smooth surface in comparison to nuts and bolts.
- Protection against corrosion
An elastic adhesive that also seals furthermore provides extra protection against various forms of corrosion. Contact corrosion can occur when two metals with a potential difference come into contact with each other. The use of adhesive, instead of screws, for example, creates a non-electrically conductive barrier between the two different metals and prevents contact corrosion.
What to pay particular attention to when bonding metals
- The type of material
Depending on the type of metal to be bonded, pretreatment may be required to ensure a proper bond. For example, raw aluminium often requires pretreatment, while, normally speaking, anodized aluminium can be bonded without needing any extra pretreatment.
- Cleaning and pretreatment
In certain cases, pretreatment with a cleaning agent or activator is sufficient. Under more severe conditions, specific primers are recommended to create a durable bond.
Practical example
SABA is working together with students of the Arnhem and Nijmegen University of Applied Sciences (HAN) on the HAN Hydromotive project. One of the challenges of this project is bonding the aluminium chassis to the floor plate. Elastic bonding is used here as an alternative to conventional joining methods, such as screws and welding.
An illustration of the aluminium chassis bonding process is described in this video.
This article was originally published as SABA - Bonding or welding metals? The benefits and drawbacks (saba-adhesives.com)
