Flying Crane
Sr. Grandmaster
Agreed. A shorter blade like a butterfly sword could be thick enough that it does not flex, but is made from a steel with a springy temper. I have some kukhri made from 5160 spring steel, but are thick and do not flex.How do you know?
That makes it more likely that it is, in fact, something that would fall into the broad category of spring steel. That includes pretty much any low-manganese, medium- or high-carbon content steels. Which is pretty much all the best blade steels.