mcq2-22

What is the primary heat source used in flame hardening?

• Electric current
• Induction
• Specially constructed burners
• Furnace heating

What is the typical carbon content range in steels used for surface hardening like flame hardening?

• 0.05% to 0.2%
• 0.2% to 0.5%
• 0.35% to 0.7%
• 0.7% to 1.5%

Which of the following is an advantage of flame hardening?

• Long hardening time
• Low fuel consumption
• Suitable for small workpieces
• High distortion

Why is stress-relieving required before flame hardening?

• To increase hardness
• To reduce fuel consumption
• To prevent hardening through
• To control the flame temperature

What is the key advantage of flame hardening for large workpieces?

• Long hardening time
• Low distortion
• High fuel consumption
• Small depth of hardening