After this, the blade still had to be heated to temper it, and quenched by being plunged into water. The rapid cooling increases the blade's hardness so that it can hold a sharp edge.
刀身打造好之後，還需要經過入水「淬火」→屬經過急遽冷卻，可以增加刀的硬度，而變得鋒利異常。