To ensure successful welding of dissimilar metals, it’s important to partner with only highly experienced, expert welding fabricators. Typically, when customers venture outside the realm of standard materials, costs increase exponentially. And since specialty materials can’t be bought off the shelf, the lead time for replacement parts and fittings is usually prolonged as well. All of these factors limit the wiggle room welders have for trial and error.
Frequently, we are called upon when existing OEM equipment has original dissimilar metals that were not joined properly. In these situations, our team will repair an existing weld or add a new component to a piece of equipment.
Even if a fabricator has previously welded one of the two dissimilar metals, this experience won’t necessarily translate to a successful dissimilar weld. Welders often need to implement completely different techniques to accommodate both types of metal. To determine the proper techniques, the physical properties of the base material and the working conditions of the completed piece must first be determined.
Depending on the application, dissimilar metal joining processes can be extremely easy or incredibly difficult. Fabricators must consider important physical properties of each base material, including:
The fabricator needs this information to determine the proper filler metal for welding the dissimilar metals. A filler material must be selected that is as close a match as possible to the weaker of the two metals; this will prevent it from weakening any further and allows the two material being joined to shrink at different rates without causing cracking in the weld, thereby forming a stronger bond at the fusion point.