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com slash brain Stuff. Welcome to brain Stuff from how Stuff Works. Hey, brain Stuff, I'm Christian Sager. The official Marvel Comics database says that Captain America's shield is a metal disc that's approximately two point five feet in diameter
and weighs twelve pounds, But Rheta. Laine at Wired Magazine did some math and figured out that it would be more likely to weigh forty three point nine pounds, despite the shield being made of a unique alloy combining vibranium, which is a fictional metal steal, and an unknown third component. Elaine also figured out that the density of the shield would be somewhere between eight thousand, seven hundred and sixty seven and four thousand, three eighty three kilgrams per meter cubed.
That is, somewhere between the density of iron and titanium. Now. In the Captain America comics, the story goes that Dr Myron McLean was attempting to replicate hercules golden mace by fusing vibranium with an experimental iron alloy. Some say it was a steel alloy, but even McClain didn't know what it was because he fell asleep when an unknown catalyst was introduced to the process. He was never able to duplicate the process, so the government painted the disk and
gave it to Captain America. But how would you forge such a thing, especially since metallurgy is so complicated. Just the forging temperature alone depends on the materials carbon content, it's alloy composition, maximum plasticity, and the amount of reduction required. Was it heated by induction or by continue was fuel fired furnaces With a material this unique, you would have
to carefully control the heating process. Now, forgibility is how easy or difficult a material resists deformation, And since Captain America's shield is indestructible, it would have to be a very narrow forging temperature range, meaning it could only be forged for a short time after heating. With metallurgical factors like crystal structure, chemical composition, and grain size at play.
The only way McClain could have diminished their influence would be by adding alloying elements, possibly compounds that easily dissolve within the metal. There are all types of elements that could have been introduced, but it's likely that Captain America's shield was forged like a super alloy. This is how metall aer just referred to iron based, nickel base and cobalt based alloys, specifically the ones that offer very high
strength at high temperatures. These really high string metals and iron based grades are the least difficult ones to work with, so that would narrow down McClain's experimental alloy to iron. Super alloys are really difficult to forge because of their narrow temperature range. You can't even use regular sizing presses and hammers on them because they'll deform. They even wear
down the tools designed for forging them pretty easily. They're also extremely expensive, like ten times the price of carbon steel. Sounds a lot like Captain America's shield, right, But how do we explain the shield's ability to absorb kinetic energy
supposedly from the vibranium in the alloy. Usually materials absorb kinetic energy through other mechanisms like plastic or elastic deformation or dynamic fluid flow, But cap shield doesn't seem to be an elastometric material, and it's not organic like polyurethane in the movies. It actually seems to reflect vibration rather than absorb it, like when Thor hits it with Mjolner in that first Avengers movie and the shock wave flattens a whole forest. Perhaps that was because the shield reached
its absorption limit. Another thing that's tough to explain is how aerodynamic the shield is. If it really weighed forty three point nine pounds, it would be difficult to throw, even for a guy in peak physical condition like Steve Rogers. In the comics, Tony Stark actually puts electro magnets under the shield to help control it in midflight, but Captain America later ditched them because they upset the shields natural balance. It seems like the soldier and the shield are made
for each other. Check out the brain stuff channel on YouTube, and for more on this and thousands of other topics, visit how stuff works dot com.