What is the Fusion Zone in Welding?

The Fusion zone in welding is the area of base metal melted as determined on the cross-section of a weld. The size of the fusion zone depends on several factors, such as:

  • welding current,
  • electrode type and position,
  • shielding gas composition,
  • and so on.

Generally speaking, the larger the welding current, the bigger the fusion zone.

The fusion zone is the area where the base metal and filler metal have been completely melted and mixed together. In this zone, the microstructure of the metals has been changed due to the welding process, and new phases (e.g. weld metal) may have been formed.

What is the example of fusion welding?

TIG welding and MIG welding are two examples of fusion welding. In TIG welding, an arc is used to heat the metals to be joined, and filler metal may or may not be used. In MIG welding, an arc is used to heat the metals to be joined, and a filler metal is fed into the weld pool.

What are fusion welds used for?

Fusion welds are used to join two pieces of metal together. The resulting joint is as strong as the original metal. Fusion welds are used in various industries, such as automotive, construction, and manufacturing.

What is fusion and non-fusion welding?

Fusion welding is a type of welding that uses an arc to heat the metals to be joined. Filler metal may or may not be used. Non-fusion welding does not use an arc to heat the metals. It includes processes such as brazing and soldering.

Heat affected zone in welding

The heat-affected zone (HAZ) is the area around the fusion zone where the microstructure of the metal has been changed by the heat of welding but no new phases have been formed.

Different zones in welding

In welding, there are three zones: the fusion zone, the heat-affected zone, and the unaffected zone.

Related Links

Fusion Zone – an overview | ScienceDirect Topics
Fusion zone geometries, cooling rates and solidification parameters during wire arc additive manufacturing – Semantic Scholar

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