NEWER TYPES OF WELDING METHODS - LASER BEAM WELDING

These types are called "newer" since these are not in use for many many years and have been developed very recently. The types are :

1.) Electron - Beam Welding

2.) Laser - Beam Welding.

LASER BEAM WELDING AND ITS PROCESS :

Lasers are devices which are capable of generating a very intense beam of optical radiation. The word "laser" is an acronym of Light Amplification by the stimulated Emission of Radiation.

As even more concentrated beam is produced, but a lower overall efficiency , with the laser beam. A CO2 laser pumped with 500 W emits far-infared light (10.6 Um wavelength) and develops a peak energy density of 80kW/mm2, yet the heat affected zone is only 0.005 to 0.1 mm wide. Oxygen blown on the surface of the metals reduces the heat reflection and increases material removal rates by oxidation ; inert gas increases heat transfer for non metals.

The laser has the advantage that vacuum is not necessary and it is finding limited but growing application, particularly for thin gauge metals.

Lasers using for work such as welding very small wires to electronic devices and similar work is called micro welding . Welding speed of about 2500 m/min is achieved on the steel sheet 1.5 mm thick.

In practice , numerical control is used to move the workpiece ; and laser's use in heavy production work is still limited.

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Mechinopedia For Mechanical Engineers

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