in a related topic to the diamond questions earlier, what does it mean to say the hardest material in the world... if you place it on a steel floor and smash at it with a sledge hammer it wont break? i know from mild common sense that that is rubbish, but could someone give me an examplpe such as that to demonstrate the unbeatable hardness of Aggregated diamond nanorods or anything!?
2007-05-30 13:07:36 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Hardness and strength are two different things. Hardness is correlated with the product of tensile strength and elastic modulus. That is, somethng has to be both strong and stiff to be hard. It's just a correlation instead of a definition, though, since hardness is actually a phenomenological property defined by indentation testing. If you can make a small intentation or scratch with something else, the latter is defined as being harder.
2007-05-30 16:32:03 · answer #1 · answered by Dr. R 7 · 0⤊ 0⤋
Swiss watches have been made for centuries with the feature that they sport a "jeweled" mechanism. For these watches, the shaft-end thrust bearings were a jewel glued to the shaft's end, or a jewel was drilled to match exactly the shaft's diameter, and pressed into the chassis to provide rigidity and durability. During those times, synthetic materials were not as strong as the small jewels the watchmakers used, and the jewels were cheap!
Consider that the force of the sledge is not smashing the diamond, but the ability of the hammer to deform and transmit the heat and vibration, which the diamond cannot. The hammer is metal, so its molecules become molten and divert energy that the diamond must absorb. The metal plate must also deform and become molten under the force of the diamond.
Consider that if you were to express the same amount of work onto the diamond in place over a period of a minute which the hammer provides in a few milliseconds, the diamond would be untouched.
Also, diamonds are NOT forever. Every diamond you see today will be graphite in less than two hundred thousand years.
2007-05-30 13:47:58 · answer #2 · answered by science_joe_2000 4 · 0⤊ 0⤋
Its been a long time since i was in school, but i do remember from my Geology class a hardness scale for minerals. Mohars Scale(spelling might be wrong but it sounds right) where Talk is 1 up to Diamond 9 with Gypsum, Calcite, Thelspar, Ortheclase, Quarts, Corundum I've missed one out, but that's What i was taught in school
2007-05-30 20:59:06 · answer #3 · answered by wigiontree 2 · 0⤊ 0⤋
Its about durability.. its not about smashing... Do you know that a diamnond blade can cut marbel stones? Can ur sledge hammer cut it? Nope.. it can smash only.
2007-05-30 13:16:09 · answer #4 · answered by Galactic_Explorer 3 · 0⤊ 0⤋
The wiki has a definition and description of hardness.
2007-05-30 13:12:37 · answer #5 · answered by Anonymous · 0⤊ 0⤋
What, have you never played that game with stone, paper, scissors? It's very scientific.
2007-05-30 13:12:51 · answer #6 · answered by Who Yah 4 · 0⤊ 0⤋