There's always the mayhem about the Japanese katana to the point that it's exaggerated. After doing some research, Understanding the Japanese katana would at least help consider some of the misconceptions about the sword itself.
The process of steel folding
There is the myth that the folding the steel took up to a million times. That statement really made me go, "HUH?!" because I guess that's just pretty impossible. Folding of steel happened during the manufacturing process was because of lower quality steel back then. To make quality steel out of what was available, iron sand was purified for 72 hours straight to get rid of the slag and later, the tamahagane had uneven carbon content. It required heating and breaking to find which ones where harder steel (kawagane) and softer steel (shingane). The kawagane are all stacked together, they are covered in Japanese paper, muddy clay water and straw ash to help even out the carbon. The process of folding is done.
In recent times, modern steel does not need to be folded because of the more even carbon content. In the past, folding steel was required because the overall composition and impurities had to removed. The heating and folding process was not done a million times. Instead, it was done usually up to fifteen times only depending on the amount of impurities. Too much folding done would make the sword too brittle where the iron layers become thinner than the atoms themselves. In modern times, katanas can be mass produced with even better quality than the traditional way. I'd want to have my blades done the modern way instead of the traditional Japanese way.
Laminating the steel
Laminating the steel involves the use of softer steel and harder steel. There is the monosteel katana but others combined softer steel types with the harder steel types. The method usually involves using the softer steel as the spine underneath the blade or as the backward part of the blade. Another method involves using medium steel, softer steel and harder steel. This might have been to increase durability and shock absorption. In today's application, there are also laminated steel knives which might have better advantage over monosteel knives.
Coating the steel
A mixture of clay and ash is done to the blade. The back part of the blade is coated in more of the clay mixture. The upper part is coated more while the lower where the sharpened edge will be is coated less. It is returned to the furnace to a temperature to just below 815.56 degrees Celsius. If it's hotter than that, the blade will break. It's then submerged into the water creating the curve. Any wrong move would destroy the blade in the process. The finished blade is ready for polishing and adding the final touches.
They're not the best swords in the world either
Forget about Kill Bill or a lot of sensationalist samurai films that exaggerate the power of the katana. The samurai sword is not that powerful as you think. It's not the best sword in the world. There are plenty of misconceptions saying like for instance, the katana had a nice sharp edge and curve, it was designed for slashing. Many show the power of the katana but there are other swords that also have that design. It can't break through armor or steel like it was butter. Sure it can cut through bone so fast but the efficiency and effectiveness of the katana relied on the wielder more than the katana itself. You know, the Riddle of Steel anyone?
Swords like everything else are subject to deterioration. In combat, you may need to replace your sword sooner or later. Even if you may have a laminated katana blade where the spine is used with softer metal to absorb the shock, it can still break at the hands of another. These weapons are not indestructible. They may either take a permanent bend or they could also break in battle.
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