Question

The mixing of flux in the casting material produces endothermic reaction.

(a) True

(b) False

This question was posed to me during a job interview.

My doubt stems from Foundry Fluxes and Refractories topic in division Foundry Introduction & Materials of Casting-Forming-Welding II

Answer 1

The correct answer is (b) False

For explanation I would say: The flux is mixed with casting while solidification that basically reacts with a network of oxides and converts them into a powder that floats on the casting so it becomes easier to separate out that part. The whole reaction takes place is exothermic. The flux is normally used after the cleaning process which prevents progressive oxidation.