Definition
A welding process in which two pieces of metal are joined by passing a strong electric current through them at the point where they touch. The metal's natural resistance to the current produces intense, localized heat that melts the contact area, and pressure applied through the electrodes fuses the pieces together as they cool. Spot welding and seam welding are the most common forms used in aircraft sheet-metal work.
Plain English
A way of joining metal pieces by squeezing them together and running a strong electric current through the joint. The metal heats up at the contact point, melts just enough to fuse, and then sets as the current stops.
Context Anchor
Seen in aircraft manufacturing and maintenance discussions about how thin metal parts, brackets, or structural pieces are joined.
Derivation
From the electrical term 'resistance' -- a material's opposition to current flow. The heat used to make the weld comes from that resistance, which is why the process carries the name.
Why Pilots Care
A pilot does not normally perform resistance welding, but understanding the term helps when reading maintenance records, repair descriptions, or manufacturing information about how aircraft parts were joined.
Intuition Check
“Resistance” here does not mean air drag or reluctance. It means electrical resistance: the metal’s opposition to electric current, which creates the heat used for the weld.
Example Sentence 1
The stainless steel firewall was assembled using resistance welding, leaving small round spots where each weld was made.
Example Sentence 2
Factory-built aircraft often have many joints made by resistance welding for speed and consistency.