Explain the term “spot welding” in autobody repair.

Spot welding is a crucial technique used in autobody repair that involves the fusing of metal surfaces through the application of heat. This process typically takes place at specific points, or "spots," on the metal panels being joined. In spot welding, electric current is passed through the metal pieces, generating heat that leads to the melting of the metal at the interface. As the molten metal cools, it solidifies to form a strong bond, effectively joining the two pieces together.

This method is particularly advantageous in automotive repair because it creates a durable joint that can maintain the structural integrity of the vehicle. It also allows for a faster assembly process compared to other methods of metal joining, making it efficient for manufacturers and repair technicians alike. Spot welding is commonly used to attach overlapping metal parts, such as in the assembly of car bodies.

In contrast to spot welding, the other mentioned processes involve different applications: using screws to hold panels (which relies on mechanical fasteners), applying paint (a surface treatment rather than a joining method), and adhering decals (which is a method of decoration rather than structural bonding). Each of these processes serves a distinct purpose in autobody work but does not replicate the fusion of metals that is essential in spot welding.