Essay On Laser Welding

APPLICATIONS OF LASER IN ENGINEERING

INTRODUCTION:

A LASER is a device that emits light through the process of optical amplification through stimulated emission. The acronym of LASER is Light Amplification by Stimulated Emission of Radiation. The four main characteristics of LASER are Monochromaticity, High Coherence, High Intensity and its Directionality. They can also have temporal coherence. Temporal coherence can produce pulses of light as short as femtosecond. There are many applications of LASER in different fields. Some of them are Optical disk drives, Laser Printer, Bar code scanner, fiber optic communication, Laser Surgery etc. Some of its engineering applications are as follows:

1.LASER BEAM WELDING Laser Beam Welding is a technique used to join multiple pieces of metal through the use of laser. The beam provides a concentrated heat source, allowing for narrow, deep welds, and high welding rates. The advantages of Laser welding are that there is no physical contact with external components, the heating is very localized, dissimilar metals can be

The absorbed intensity transformed into heat within the penetration depth of laser radiation .And when the illuminated spot on the surface reaches the boiling temperature, material removal starts due to the process of vaporization. The material is heated by powerful light pulses of 10-4 to 10-3 seconds duration. The advantages are non-contact process, problem of wear broken drills, faster process, high precision and possibility of drilling hard material. These techniques are used in perforation in plastic, nozzles and nylon buttons, aircraft engine turbine blade etc. Usually pulsed carbon dioxide and alexandrite lasers are used. Pulsed laser micro drilling is quite successful for some special operations for both metals and nonmetals. For some metals the alexandrite laser gives a cleaner entrance hole with more roundness and finer edges when compared with other