What does "differentially hardened" mean and how do you do it?

Many medieval weapons were differentially hardened, which means that they were made of materials of varying hardenability and were heat treated in order make certain parts of the weapon harder than others. This is often the case with axes, hammers, and spears, and also with certain kinds of historical swords. In this video Nathan demonstrates how Arms and Armor creates a differentially hardened spearpoint.

[@Wf250]

Great video! thank you for teaching this! God Bless.

[@armsarmorinc.4153]

My pleasure!

[@dustinleebladesmith9135]

Good stuff!

[@raphlvlogs271]

was the same thing done no axe heads?

[@armsarmorinc.4153]

Yes

[@KartikSingh-oo5tq]

is tempering in an oven required in the case of slack hardening too?

[@armsarmorinc.4153]

not if you do it right!

[@mozes3280]

Isn’t the sword supposed to be harder to bend at the base of the blade and more flexible as it gets closer to the tip? Isn’t that what differentially hardening is for in medieval swords ? Ty

[@armsarmorinc.4153]

nope, that is due to the distal taper where the sword gets thinner as it gets to the end. Swords that are differentially hardened will be harder at the edge than in the center of the blade.

[@gobbygoberton7113]

Are you implying that medieval Europeans did produce differential harden steel?

[@armsarmorinc.4153]

Not as a desire to do so but as a function of material and processing. The steel/iron mix of the middle ages had variable carbon content in most items and they used this to advantage in design and function. Our steel today is more highly refined then they would have achieved.