Question

Which of the following methods is best for preventing the solutions of gases in metals?

(a) Bubbling of gas

(b) Vacuum melting

(c) Venting arrangement

(d) Elements inclusion

The question was posed to me during an interview.

This intriguing question originated from Gases in Metals in portion Pouring – Gating Design, Melting Furnaces, Melting and Casting Quality of Casting-Forming-Welding I

Answer 1

The correct answer is (b) Vacuum melting

Best explanation: Vacuum melting is increasingly being used for preventing the solutions of gases in metals and the combinations of reactive elements in the melt. Additions in the ladle, rather than in the melt, have been found to be more effective for controlling the gases and chemical compositions.