What Are The Classifications of Welding

What are the classifications of welding? Welding is mainly classified into three categories based on the physicochemical properties of the welding process. The core conclusion is that welding can be divided into fusion welding, pressure welding, and brazing, each category containing various specific welding methods.

1. Fusion Welding (Fusion Welding)

Core characteristics: During the welding process, both the base metal and the filler metal are heated to a molten state, and a joint is formed without applying pressure.

Common types:

Arc welding: Uses an electric arc as the heat source, such as manual arc welding, submerged arc welding, and gas shielded welding (CO₂ welding, argon arc welding).

Gas welding: Uses the combustion of combustible gas (such as acetylene-oxygen) as the heat source; the equipment is simple and the operation is flexible.

Electroslag welding: Uses electroslag as the heat source; suitable for thick plate welding; high welding efficiency.

2. Pressure Welding (Pressure Welding)

Core characteristics: Pressure is applied to the workpiece during welding; some methods require heating (but the base metal does not melt or only partially melts), and the pressure is used to tightly bond the joint.

Common types:

Resistance welding: Utilizes contact resistance for heating, such as spot welding, seam welding, and projection welding. Suitable for mass production of thin plates.

Friction welding: Generates heat through mechanical friction, resulting in stable joint quality. Suitable for butt welding of round workpieces.

Ultrasonic welding:Utilizes ultrasonic vibration energy. Suitable for welding precision, thin-walled parts (such as electronic components).

3. Brazing

Core characteristics: Uses a filler metal with a melting point lower than the base metal. Upon heating, the filler metal melts and wets the base metal surface. After cooling, a joint is formed, and the base metal does not melt.

Common types:

Soft brazing:The filler metal's melting point is below 450℃, such as tin soldering (electronic circuit connections).

Hard brazing: The filler metal's melting point is above 450℃, such as copper brazing (mechanical parts connections).