Originally posted by darthgoober
I'm pretty sure that has a lot to do with how tightly the wire is stretched. And whether it's springy or not, it's still tempered carbon steel according to it's Wiki article(though I guess it could be wrong since it's wiki)..."Piano wire is a specialized type of wire made for use in piano and other musical instrument strings, as well as many other purposes. It is made from tempered high-carbon steel, also known as "spring steel". Music wire is another name for piano wire: it is used for the cores of strings, which may be wound with other materials. Music wire is used for a variety of stringed instruments that use steel strings, such as guitars."
I guess it's possible that concrete is more durable than and equal amount of "springy" steel, but I'd have to see some proof to fully buy it. I'm not asking you to go find proof on it mind you because it has nothing to do with the thread topic, just pointing out my general view on it because I generally consider steel to be the tougher of the substances generic types.
To be honest, no one is going to be able to objectively answer a question on material durability based on real chemistry, because there isn't really a catchall durability for materials.
Diamond, for instance, is the hardest naturally occuring material. However, it certainly isn't the toughest. Jadiete, iirc, has that distinction, but is not as hard as diamond. Besides these two relatively umbrella terms, we also have the various tensile strengths, fracture strengths, impact strengths, buckling strengths etc.
Illustrating using the mentioned examples as parallels, a wheat straw can rend concrete while glass cannot not because it is simply more durable, but because it is "tougher" (using the catchall term). However, a straw cannot cut glass because the latter is "harder".