Why do you strike the sword repeatedly with a hammer when casting the sword?

The purpose of repeatedly beating the sword with a hammer when casting a sword is to exert pressure on the metal blank to make it plastically deformed, so as to obtain a forging with a certain shape, size and mechanical strength.

In addition, repeatedly beating the sword can also eliminate inclusions, even composition and dense structure, and sometimes refine grains, thus greatly improving the material quality, improving the toughness of the sword and making the oxide layer fall off. In addition, according to the principle of work hardening, its strength and hardness can be increased, thus obtaining good comprehensive properties.

Extended data

The process of casting a sword:

1. hammer: the iron block is melted in the furnace, and the sword blank is made by carburizing process, which is repeated many times, depending on the quality of the sword (hard sword, soft sword or martial arts sword).

2. File flat: File flat with a steel knife, so that the thickness of the blade is moderate and there is a certain inclination between the ridge and the blade. The ridge of the sword must be in the middle of the blade and in a straight line. ?

Third, quenching: the traditional quenching method is adopted, and after "strong forging" and "softening" treatment with special quenching agent, the sword body is both rigid and flexible, full of elasticity and ductility.

4. Polishing: Put the filed sword on the stone and polish it. Polishing is twice as difficult as hammering and filing.

Steel grinding: an elastic sword will be sharpened with steel blocks; Or tie the blade tightly with a steel ruler and grind it on a stone.

6. Mosaic: After polishing, the sword body is engraved with the pattern, sword name, shop number and words instructed by the customizer with a steel needle, and inlaid with red copper. After chemical treatment, the green light sword body is golden yellow, which produces color contrast and has a sense of brilliance and treasure.