Argon arc welding differs from all other types in that this process uses an electric arc with argon as a protective medium. An inert gas is supplied primarily to protect metals from contact with oxygen during processing. In this article, you will learn the basic principle of argon welding, as well as in what cases it is used.
How it Works
With suitable oxygen contained in an inert gas atmosphere, you can weld metal to metal. You apply the maximum amount of energy to the metal part that you intend to weld by using a welding needle to spark the arc. The heating and cooling action creates a path of ionization of the carbon and oxygen components of the arc.
Air flow provides the vacuum or partial vacuum that prevents air and oxygen from mixing in a process known as sublimation, so the metals remain in air alone. In this process, the metal is not directly heated by the electric arc; instead, the metal undergoes secondary heating as it strikes the arc. During the process, the metal is lowered into a partial vacuum by convection that has ignited the arcs. An inert gas shield prevents the gas from mixing with the metal. Some people call this process ultraviolet welding, but its function is not to fuse the metal by direct contact, rather by making an otherwise permeable metal into a more permeable metal. The welding medium cannot directly fuse or burn the metal, but by generating an ionic pathway, it provides greater energy levels to bond the metal to the metal electrode.
An important aspect of the ionic pathway is the path that the oxygen path takes. While it is not known exactly, a significant amount of time is required for oxygen to diffuse through the metal, so welding can be difficult or impossible for metal parts that are hydrated or hydrophobic. In most cases, if there is not a significant amount of metal available to absorb this oxygen, the welding process must be interrupted and the metal is heated further to accommodate this path of ionization.
Besides the path of ionization, another important aspect of the ionic pathway is that the metals can still cool to metal again. This process allows a significant temperature reduction and cools metal to metal by reducing the ionic pathway. When the metal cools, the metal-ion pathway is disrupted. This process is known as welding, and sometimes it is used for welding lighter metals to heavier metal with the metals cool to metal.
Another interesting thing about this process is that there are two pathways for the metal to metal pathway; both operate at a different temperature. This is the reason that you have two weld points, one for metals at relatively high temperatures, and one for metals at relatively low temperatures.
There are three methods to reduce the amount of metal on the welding head or welding tool.
Throwing metal: This is the method used when the metal is at relatively low temperature, such as welding lead plates. The metal is thrown or thrown from the head directly onto the metal electrode. Some iron alloys, such as ferritic, are preferred for this process. Warming metal: Warming metal: This method is used to weld extremely cold metals, such as copper alloys and powdered stainless steel. When a sharp-edged, thin metal bead is heated to very high temperatures, the metal beads are heated to the metal electrode.