One of the most widely used metal fabrication processes is welding. Welding is the fusion of metal parts to form unique metal structures. The welding of different metal elements often presents a challenge because the metals have different mechanical properties. There are several applications, however, which require weldings made from dissimilar metals. In order to achieve good welding results, it is important to use the right welding techniques. Here is a look at some of the most popular welding techniques used to join together metals of different compositions.
Also known as explosion cladding, explosion welding involves the use of controlled explosive detonations to fuse together two or more dissimilar metals at high pressures by using chemical explosives. This solid-state welding process is most widely used to clad carbon steel with a thin coating of rust-proofing material, such as nickel, titanium, brass, zirconium, or stainless steel. But that does not imply explosion welding cannot be used to other non-compatible metals. As a matter of fact, this welding process can be used to weld almost any metal combination, including those that are metallurgically compatible and those that are not. What is more, this process can be used to clad multiple layers onto the surfaces of the base metal, and each layer may comprise a dissimilar metal or metal alloy.
Like in explosion welding, friction welding requires heat to join dissimilar metal components. The heat is produced by rubbing two metal materials against each other. This welding technique is suitable where mass production is desired. Another notable advantage of friction welding is that it eliminates the need for filler material, resulting in lower cost per weld. This welding method can be used to successfully weld a wide range of dissimilar metals including bonding stainless steel to other types of metal or metal alloys.
As the name implies, no heat is required in cold welding. Instead different metals are joined with the use of pressure alone. This makes cold welding ideal for fusing together heat-sensitive metals and metal alloys, as the workpieces are welded without contamination from vapours or sparks. What is more, there is no need for any temperature-controlled environments, as the welding is effectively performed under room temperatures. This process is normally used to fuse aluminium to copper. But it can also be used to join together other dissimilar metals, like aluminium to steel, for instance.