Welding, Weldability And Types Of Welding

Welding is the process of joining similar metals by application of heat with or without application of pressure and addition of filler material. The result is a continuity of homogeneous material, of the composition and characteristics of two parts which are being joined together. The application of welding are so varied and extensive that it would be no exaggeration to say that there is no metal industry and no branch of engineering that does not make use of welding in one form or another. In fact, the future of any new metal may depend on how far it would lend itself to fabrication by welding.

The term "Weldability" has been defined as the capacity of being welded into inseparable joints having specified properties such as definite weld strength, proper structure , etc. This means, of course, that if a particular metal is to have good weldability, it must be welded readily so as to perform satisfactorily in the fabricated structure. However, the real criterion in deciding on the weldability of a metal is the weld quality and the ease with which it can be obtained.

Weldability depends on one or more of five major parts :

(1) melting point

(2) Thermal conductivity

(3) Thermal Explosion

(4) Surface condition, and

(5) change in microstructure.

TYPES OF WELDING :

There are so few types of welding process, they are :

1. Gas Welding.

2. Arc Welding.

3. Resistance Welding.

4. Thermit Welding.

5. Solid State Welding.

6. Newer Welding.

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