Topic: Manufacturing Processes
Brass is welded using oxidizing flame due to
- A. $O_2$ is prevented entering from the atmosphere
- B. Zinc is prevented from evaporating
- C. Zinc is oxidised
- D. All of the above
Answer: B. Zinc is prevented from evaporating
Explanation: Brass is an alloy of copper and zinc. During gas welding, the high heat causes the zinc to evaporate rapidly since its boiling point is relatively low. Using an oxidizing flame creates a protective scum/layer of zinc oxide on the molten pool, which suppresses the further evaporation of zinc.