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Material Tougher Than Diamond Developed
sporkme has handed us a link to a New Scientist article. The piece outlines the development of a new substance reported to be stiffer than diamond. A team of scientists from Washington, Wisconsin, and Germany combined the ceramic barium titanate and white-hot molten tin with an ultrasonic probe. The new material was, in some tests, almost 10x more resistant to bending than diamond. Composite materials researcher Mark Spearing of Southampton University comments on the result: "The material's stiffness results from the properties of the barium titanate pieces, Spearing says. As the material cools, its crystal structure changes, causing its volume to expand. 'Because they are held inside the tin matrix, strain builds up inside the barium titanate,' Spearing explains, 'at a particular temperature that energy is released to oppose a bending force.'"
I love them almost as much as dupes. :) Material Tougher Than Diamond Developed...(in some tests), like say: "The tests were carried out at a variety of temperatures. Between 58C and 59C the samples became stiffer than diamond."
Not to knock the experiment though, it seems interesting, and I'm sure there are all sorts of new exotic materials on the horizon.
Actually the word diamond is derived from the Greek word adamas, so in fact diamond is adamantium.
Don't conflate hardness with strength or stiffness. Hardness is not well quantified. For hardness we refer to the Mohs scale, which will tell you which of two substances is the harder, but doesn't strictly quantify hardness. A claim that substance A is "twice" as hard as substance B probably refers to the Young's Modulus, or stiffness, rather than to hardness.
A common way to measure the Young's modulus is to support a sample of the material on two struts, and then apply pressure from above to the center of the sample. The less it bends, the higher the Young's modulus. The apparatus looks like this.
Strength is a different quantity. Strength is the amount of force needed, per unit cross-sectional area, to cause the material to fail. For tensile strength, this means pulling apart. For compressive strength, it means collapsing. A material with great tensile strength can have a great weight hung from it without snapping, and a material with great compressive strength can act as a pillar to support a great deal of weight.
The article claims nothing about the strength of this material.
TFA says it's stiffer than diamond, that doesn't mean that it's harder than diamond.
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... doesn't mean it's tougher than diamond. Any mechanical engineer will remind you that strength, stiffness, and toughness are three different properties. IIRC my materials engineering class 15 years ago, they are approximately:
strength: maximum load before failure
stiffness: resistance to deformation
toughness: tendency to avoid reduction in strength over time in the face of repeated deformation
also:
hardness: ability to resist permanent deformation, particularly vs. small surface insults like scratches and indentations.
Diamond is very strong, very stiff, and very hard but it is definitely not tough: large blocks of the stuff are fairly brittle and tend to crack and chip. In fact extremely stiff materials are often not tough because they are brittle. OP has a very screwed-up title.
From TFA, we have no idea whether or not this new material is either strong or tough or hard: only that it is extremely stiff. (cue tasteless jokes)
I stole this sig from someone cleverer than me.