Welding Dissimilar Metals is desirable for many reasons. Whether you have an issue with mechanical wear problems, or a high-temperature situation, different metal properties are required for different applications. More often, Friction Welding accounts for nearly half the welding of Dissimilar Metals.Benefits of Welding Dissimilar Metals include:
Welding Dissimilar Metals using conventional welding techniques, creates a lot of heat, which erodes the strength of the welded joint. Friction Welding is most effective because of its solid state process. The American Welding Society (AWS) classifies Friction Welding as, a solid state welding process that produces a weld, at temperatures lower than the melting point of the base metals, under compressive force contact of work pieces rotating, or moving relative to one another, to produce heat, and plastically displays material from the surfaces.
With Bi-Metal welds, as with all welds, an investigation of the HAZ (Heat Affected Zone) will determine crack sensitivity, ductility, and susceptibility to corrosion. If both materials have mutual solubility, you will have a successful metal joining. The micro-structure of this union is important to review. When welding Bi-Metals, you need to consider thermal expansion of both materials. If they are widely different, there will be internal stress on the HAZ during any temperature change of the weldment, which could lead to cracking. Bi-Metal Consideration on an electrochemical scale, susceptibility to corrosion, is also necessary. Sometimes, it is necessary to introduce a third metal, that is soluble to each, in order to produce a successful weld.
With Friction Welding, only a small amount of the base metal is heated. That metal is thrown from the joint creating a mushroom effect of material, or flash, that can be removed or left on. The flash that is created over the upset area is repeatable, once an R&D has been performed. Parameters will be calculated and recorded so that the process is repeated with each run.
Spinweld’s customers’ span nearly every market, applying friction welding to a wide range of applications. The technology to join different materials with a fast, environmentally friendly, and highly-controlled process is beneficial to all industries.
We invite you to call or contact us with your potential application and learn if our process can save you money, while often yielding better parts!