Question

Why alternating current is most suitable for resistance welding?

Answer 1

Answer:

resistance welding is a thermo electric process used for joint two metallic parts.

Electricity is used to provide heat.

Now, we know that Alternating Current is a pulsatile current having sine or cosine functions.

So in each cycle, the current crosses zero mark. This provides a time to cool down the joined parts of the metal.

But if we use direct current, we get continuous supply of heat , which doesn't allow metal to cool and solidify.

That's the reason we use alternating current. Hope you will be able to understand.