Slashdot Mirror
Graphene Super Paper Is 10x Stronger Than Steel
Elliot Chang writes "The University of Technology in Sydney recently unveiled a new type of graphene nano paper that is ten times stronger than a sheet of steel. Composed of processed and pressed graphite, the material is as thin as a sheet of paper yet incredible durable — this strength and thinness gives it remarkable applications in many industries, and it is completely recyclable to boot."
"it’s two times as hard, six times lighter and ten times higher in tensile strength"
Well, to the materials scientists I work with, those words sound like advertising more than useful information.
Two times as hard as steel. Steel in what condition? There is a very wide variety of steel alloys, and these can be heat treated to be as whatever hardness is necessary. Find a piece of mild steel (the kind of stuff you might find at the hardware store) and try to scratch it with something hard. You can scratch it pretty easily, but try again on a piece of stainless steel cutlery and you'll probably find it quite a bit more difficult. Both are steel.
Six times lighter. Per unit volume? Ok, but how do the other characteristics compare given the same volume? Or given the same weight? The article doesn't give any real detail or any frame of reference.
Ten times higher in tensile strength - again, if you want to compare to steel you need to give the alloy grade (grade refers to composition, not quality), and the heat treatment - anyone who's bought nuts and bolts at the hardware store has noticed that these metal items are available in different strength grades even within the same basic metal family.
Those claims sound just like those given for aluminum - it's lighter (per unit volume), stronger (per unit weight), etc. But, in service, where toughness (ie. impact resistance, the ability to deform plastically before fracturing, etc), steel beats aluminum hands down.
Not that I'm a big fan of steel or anything, it's just that these comparisons are often incomplete and therefore meaningless. It's too bad the article writer didn't include any actual mechanical property values.
Putting moderation advice in your
bullet, if the bullet is fired from a WWII period carbine with standard powder load. More powerful than a locomotive, specifically an R100 with a half-load of diesel traveling on level ground, with standard moisture conditions. Able to leap tall buildings, that is any vertical structure with a height of 2,000 meters or less, in a single bound, a bound beind defined as a vertical motion impelled by a single push of the foot against the earth, being level with the first floor of the building's entrance, and also considering stable wind conditions, standard humidity, temperature, and pressure, and no precipitation.
Yes. It's called the Munroe Doctrine.