Laser beam welding is a technique in manufacturing which uses high intensity laser beam for joining different materials together. The characteristics of laser beam is that it is coherent and have monochromatic wavelength. The laser beam has high energy content and very low divergence. It produces heat when it strikes the surface
Laser Source for Welding:
Mainly, gas laser (Co2), solid state laser (Nd:YAG and ruby lasers) and Fiber laser are primary types of lasers used in welding.
Characteristics of Laser Beam Welding include the following:
The power density of laser beam is high, and It is of the order 1 MW/cm2. Due to high power density it has small heat-affected zones. So, the rate of heating and cooling is high.
For welding purpose pulsed or continuous laser beams are used.
Laser welding is a versatile process since it is capable of welding different types of material like carbon steels, stainless steel, HSLA Steels, aluminum and titanium.
It produces high quality weld.
Laser welding can easily accessible since the beams can be focused, aligned and directed by optical elements.
Laser beam can be focused on a small area, permitting the joining of small, closely spaced components with tiny welds.
Due to high laser penetration power it’s aspect ratios (i.e., depth-to-width ratios) is high i.e. 10:1.
Application of Laser beam welding:
The application range of LBW covers the finest welding of non-porous joints in medical technology to precision spot welding in electronics or the jewellery industry, to deposit welding in tool and mould-making and welding complete car bodies in auto mobile construction.
Laser Brazing: Brazing is a joining process that uses a filler metal or alloy to melt at temperatures above 450°C.
Laser Soldering: During the soldering process, the filler metal or alloy is heated up-to melting temperatures less than 450°C. So, generally laser output power less than 100 watt is required for melting the filler material
Laser Plastic Welding: Diode lasers are the ideal choice for plastic welding. With different wavelengths ranging from 808 to 1470 nm
Spot and seam welding: Seam welding are a variation of spot welding. In laser seam welding, the part to be welded is moved or rotated under the focus head allowing laser spot welds to overlap.