Laser beam welding, Mechanical Engineering

LASER BEAM WELDING


In this process, fusion is achieved by directing a highly concentrated beam to a fine spot. The word LASER  is an abbreviation of Light Amplification by Stimulated Emission of Radiation. High energy output is available from CO2 Laser and Nd-YAG Lasers. In CO2 Lasers, CO2 is the lasing medium. A high voltage of the order of 20 to 30 KV is applied through a pair of electrodes. This high voltage excites the gas particles. When a fundamental particle of light such as
photon hits the excited gas CO2 gas atom, the excited CO2 gas atom returns to normalcy. But, in the process it emits another photon with same direction, amplitude and frequency. This achieves the light amplification by stimulated emission of radiation.

The emitted photons travelling in the same direction, hits the mirror in one direction, reflected back & hits the mirror in the opposite direction. Within a short time, a narrow, coherent beam of laser light is formed, a part of which comes out through the partially transparent output mirror. This beam is further focused to achieve the welding or cutting, etc. Depending on the lasing medium, we have solid, liquid, gas and semiconductor lasers. CO2  Laser is the most popular gas laser and Nd-YAG is the most popular solid laser used for industrial applications. Laser beam can be used to weld otherwise difficult to weld metals such as nickel, tungsten steel, titanium and columbium. This can also be used for cutting hula rubber, plastic, paper, cloth, etc. Lasers are used in medical, electronic,  automobile, sheet metal
works, aerospace, defence, communication and fabrication industries.

Posted Date: 9/13/2012 7:06:16 AM | Location : United States







Related Discussions:- Laser beam welding, Assignment Help, Ask Question on Laser beam welding, Get Answer, Expert's Help, Laser beam welding Discussions

Write discussion on Laser beam welding
Your posts are moderated
Related Questions

Q. Pressure and Temperature in Unfired pressure vessels? The design pressures and coincident maximum and minimum metal temperature, shall be determined by carefully considering

Illustrate the following terms:- a) Mechanism and Inversion b) Slip and Creep of belt drive c) Centrifugal Tension of belt drive d) Initial Tension of belt drive

Once the total volume of an individual vessel has been established the detailed dimensions or mechanical design can be performed. Much of this is based on "Rules of Thumb"  built f

ELECTRON BEAM WELDING In this process fusion is achieved by focusing a high power density beam of electrons on the area to be joined. Upon striking the metal, the kinetic ener

Use the graphics and the equation to define the term principal stress and principal planes.

Types of couple: Explain about different types of couple?  Sol.: There are mainly two types of couples: 1 . Clockwise Couple   A couple whose tendency

Determine the maximum bending stresses: A rectangular beam of breadth 100 mm & depth 200 mm is simply supported over a span of 4 m. The beam is loaded with a uniformly distrib

Effect of the parameters in spot welding The passage of more current than what is required causes the following defects. I. Weld expulsion ii. Cavitations iii. Weld cracking

Sweep pattern It is used to sweep the complete casting by means of a plane sweep. These are used for generating large shapes which are axis-symmetrical or prismatic in nature s