Flash welding

From GAWDAwiki

Flash welding is a form of resistance butt welding in which work-pieces clamped between dies are slowly brought together, allowing current to travel between them. Successive points of contact heat quickly, melt and are expelled from the joint, creating the “flash,” from which the method derives its name.

Once a pre-determined amount of material loss has occurred, the interior portions of the base pieces are forged together, expelling melted material and contaminants. The result is a solid-phase forge weld.^[1]

Advantages of Flash Welding

• Well suited for welding complex or large pieces
• Energy efficient
• Localized and evenly-heated zones
• Relatively short weld time¹

Disadvantages of Flash Welding

• Elevated safety risk due to flash
• Loss of metal during flashing and upsetting
• Restricted to work pieces with similar shapes^[2]

References

1. http://www.twi.co.uk/content/kssaw006.html
2. http://www.welding-technology-machines.info/resistance-welding-processes-and-equipments/disadvantages-of-flash-welding.htm