Jed Bothell Vice President Atlas UHV
A S S E M B LY: m e t h o d s
What methods are available to bond dissimilar metals for use in critical applications? Bimetal components do not require bolting or the use of an adhesive. Advanced joining technologies enable engineers to reliably apply the ideal properties of one metal with those of another, offering an advantage in several industries, including the vacuum, cryogenic, and semiconductor sectors, and others.
Where many applications might allow for the use of mechanical bolting or an adhesive or sealant to bond two dissimilar metals, high-performance applications in aerospace, medical, cryogenic, and vacuum often require greater strength and longevity. Mechanical fasteners are ideal for several applications but are subject to cracking or corrosion, depending on the environment, and add weight to an assembly. Adhesives provide a solid bond at the beginning of use, but they typically degrade over time.
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December 2021
www.fastenerengineering.com
Additionally, the process of joining certain materials, such as aluminum to other metals, is challenging. Its tenacious oxide surface protects it from rust-like oxidation, which is visible on iron and steel, preventing close metal-to-metal contact. Fortunately, there are alternative methods for bonding dissimilar metals that ensure a solid bond. The two most recognized methods are explosion bonding (or explosion welding) and diffusion bonding. Each one offers benefits and drawbacks, depending on the application. But both DESIGN WORLD
