Question

In electric arc wire spray process, preheating of metal before welding is mainly done to prevent surface cracking.

(a) True

(b) False

This question was posed to me in homework.

I'd like to ask this question from Salvaging Techniques in section Salvage of Defective Castings of Casting-Forming-Welding I

Answer 1

The correct answer is (a) True

Easiest explanation: In salvaging of the casting metal, the weld-ability may depend on special techniques. For example, preheating before welding is mainly done to prevent cracking due to thermal stresses and to reduce residual stresses, distortion and hardness of the casting metal. This makes electric arc wire spray process easy and reliable.