The maximum heat in resistance welding is at the-

Explanation

Explanation: Asperities between touching plates the resistance of the joint R is a complex fact to know because it is compared of The resistance of the electrode The contact resistance between the electrode and the workpiece The contact resistance between the two workpiece plates The resistance of the workpiece plates The amount of heat released is directly proportional to the resistance. It is likely to be released at all of the above-mentioned points, but the only place where a large amount of heat is to be generated to have an effective fusion is at the interface between the two workpiece plates. Therefore, the rest of the component resistance should be made as small as possible, since the heat released at these places would not aid in welding. The critical variable in a resistance welding process is the contact resistance between the two workpiece plats and their resistance themselves. The contact resistance is affected by the surface finish on the plates since the rougher surface has higher contact resistance.