Question

Season-cracking of brass can be prevented by cold-working at

• A. 15$^\circ$C
• B. 100$^\circ$C
• C. 300$^\circ$C
• D. 550$^\circ$C

Hint:

Season cracking in brass is mainly prevented by removing residual stresses through stress-relief heating at about 300$^\circ$C.

Answer 1

The Correct Option is C

Step 1: Understanding season cracking.
Season cracking is a type of stress corrosion cracking observed mainly in brass alloys. It occurs due to the combined effect of residual tensile stresses and a corrosive environment such as ammonia.
Step 2: Role of residual stresses.
Residual stresses are introduced during cold working processes like rolling or drawing. These stresses make brass susceptible to cracking over time.
Step 3: Prevention method.
Season cracking can be prevented by stress-relief treatment. Heating brass to about 300$^\circ$C removes residual stresses without significantly altering its mechanical properties.
Step 4: Conclusion.
Cold working followed by stress relieving at around 300$^\circ$C effectively prevents season cracking in brass.