The well-known Gas Metal Arc Welding was developed and is in use since the early nineteenth century. It gets in comparison with Laser Beam Welding, a new welding method that is industrialized since the late eighties and has become a common practice in the automotive industry as well as in the production of pipes for liquids.
Gas metal arc welding (GMAW) refers to welding which requires a current from an electrode. This creates an arc heating both the electrode and the workpiece metal. It is enabling the two to melt and weld together. Traditionally, TIG and MIG welding have been the manufactoring process of choice for welders. GMAW is considered a good choice because of its excellent finish.
Metal Inert Gas (MIG) Welding uses a consumable wire electrode to create an electric arc between it and the metal being welded. This electric arc melts the metal being welded and the wire and welds both metals together. A gas known as shielding gas is fed through the welding gun enabling the workpiece to be shielded from air contamination. A constant voltage Direct Current (DC) is commonly used in gas metal arc welding (GMAW). However, alternating current or constant current systems are also used. TIG welding uses a tungsten electrode to create the electrical arc and a handheld filler is used. Whereas in MIG welding the electrode also acts as a filler.
Laser welding is used more frequently in industrial processes because it has wider application than traditional welding as less heat is created because the beam is so focused. This means that heat transfer to the workpiece is much less and the metallurgical structure is less affected and the quality of the weld is much higher than with traditional forms of welding.
Laser welding is a much more accurate manufactoring process and welds can be as small as one hundredths of a millimetre. Small pulses of heat are used to create the weld which leads to a higher quality finish which is stronger providing a better depth to width ratio. Depending on the power of the laser, welding penetration up to 15 millimetre of steel or stainless steel can be achieved.
Another distinct advantage of laser welding over other methods is that lasers can weld a greater variety of metals such as high strength stainless steel, titanium, aluminium, carbon steel as well as precious metals like gold and silver.
With laser welding, welds are much more accurate and finish is superior as is strength. The manufactoring process is therefore excellent for fine components and it can be used in areas where there is limited access. Lasers enable precision and quality where required for fine components.
The benefits of laser welding for modern processes over traditional welding are many. Laser welding overall has a much wider application and an ability to weld a greater number of metals to a much higher quality which is vital where precision engineering is required.