If the chisel edge dulls quickly after sharpening, which process is indicated?

• A. Hardening and tempering
• B. Polishing only
• C. Annealing
• D. Quenching only

Answer: (A)

Edge retention on a chisel depends on having a hard yet tough edge. If the edge dulls quickly after sharpening, the metal isn’t resisting wear as it should, which points to improper heat treatment. Hardening and tempering is the right process because hardening raises the steel’s hardness to resist abrasion, while tempering reduces internal stresses and increases toughness so the edge won’t chip or dull from minor impacts. Polishing alone won’t increase hardness, so wear continues; annealing softens the steel and makes dulling easier; quenching alone can make the edge very hard but brittle, leading to chipping. So the indicated process to achieve a durable, sharp edge is hardening and tempering.