Temper: The Definition and Meaning

Temper, in the context of metallurgy and sword-making, refers to the precise heat treatment process that alters the hardness and flexibility of a blade. After a sword is forged and hardened—usually by heating it to a high temperature and then quenching it rapidly—the blade can become excessively brittle. This brittleness arises from internal stresses locked within the steel during the rapid cooling process. Tempering is used to relieve these stresses, fine-tune the steel’s microstructure, and balance hardness with the toughness required for an effective, durable weapon.