The Katana (sword) of the samurai warrior is one of the best-known edged weapons in world military history.
It is also probably the finest, being made using metallurgical skills based on tradition and observation, a process that has enabled 800-year-old swords to be preserved in perfect condition.
Created from iron sand drawn from river beds, a mass of raw iron was created that was successively beaten and stretched to produce a billet of steel from which the sword bladed would be hammered.
Apart from low-grade daggers, a samurai blade was of a composite construction whereby a super-hard core was embedded partly within a more resilient and less brittle outer section. A wavy line along the blade indicated where the two parts met. When the sword was quenched, coatings of clay of varying thickness allowed the body to stay springy, so that as the cutting edge sliced through its target the body absorbed the shock of impact.
A skilled swordsman could deliver a killing stroke direct from the scabbard in one devastating swoop. Legend tells of one samurai who struck his victim so quickly and keenly that the man walked on for six paces before falling into two pieces.
It’s amazing to me that katanas have lasted for 800 years while maintaining their strength and edge. This makes me wonder how the metallurgic process you’ve mentioned works. I would imagine that katanas sold now are able to be made more easily and quickly than swords in the past.