Upgrade your account to a Community Supporter account and remove most of the site ads.
Rocket your D&D 5E and Level Up: Advanced 5E games into space! Alpha Star Magazine Is Launching... Right Now!

Reply to thread

Message: <blockquote data-quote="buzzard" data-source="post: 1147308" data-attributes="member: 3003"><whips out metallurgist hat>OK the problem here is that D&D uses a bad term. It seems logical enough that hardness would work to describe how "hard" something is to break, but it doesn't. It causes complications based on real work hardness meaurements. In the real world hardness is measured by how much force is required to locally deform a substance . Usually this is done using an indentor. It is directly indicative of the strength of the interatomic bonds in the substance (be they metallic, covalent, or ionic). However this does not tell you anything about how much energy it will take to break the material. When you break something you, in almost all cases, induce fracture. Thus the key to how tough (which means how much energy is needed to break) a substance   is, can be related to how hard it is to propagate a crack through it. Metals are generally quite tough. They are tough because they are malleable. Stone, diamonds, and glass are not tough because (at room temperature) they are not at all malleable. This has to do with the nature of the bonds, and the atomic stacking. What does malleability have to do with cracks? Well, a crack works by concentrating stress at the crack tip. Because of this concentration, a mild load is able to break very strong bonds, because it is only doing it to a few bonds at a time. In the case of a malleable material, a region around the crack tip deforms, which distributes the stress, thus blunting the crack tip. Unknown to most people it is possible to make ceramics which can be tough. You just do it by playing some complicated games (too complicated to explain here). I have played with a ceramic hammer before. However this technology is certainly too modern for a D&D setting. But, to get back to game mechanics, the value for glass is probably fine. Glass has an amorphous structure which, at room temperature, is incapable of rapid deformation because there is no way for atomic stacks to slide past each other in a uniform manner (which is about as simply as I can put it without explaining dislocation theory). I definitely don't recommend upping the hardness for diamonds. They are, like glass, extremely brittle. If you happen to be a De Beers heir, you can test this out by hitting one with a hammer. It will shatter.  Also, please don't starting thinking about tensile strength. It is generally not a useful measure for about any practical purpose. Yield strength is generally accepted as much more useful, though in this case it still isn't a good bet. If you take a small enough glass fiber, which has no cracks, it will have an enourmous tensile strength. Diamond would be even stronger by this measure. However both of these materials have poor toughness, which is what you should care about. If you want a tough material it has to be both strong and malleable. This pretty much limits you to metals (and composites, but D&D doesn't tend to have those). buzzard</blockquote>

Verification