1 00:00:01,920 --> 00:00:07,160 Speaker 1: Welcome to brain Stuff production of iHeart Radio. Hey brain Stuff. 2 00:00:07,160 --> 00:00:09,640 Speaker 1: I'm more in Vogelbaum, and today's episode is a classic 3 00:00:09,680 --> 00:00:13,399 Speaker 1: from our former host, Christian Sagar. The team here around 4 00:00:13,400 --> 00:00:16,560 Speaker 1: the currently virtual office loves a comic book and has 5 00:00:16,600 --> 00:00:19,040 Speaker 1: been delighted that Marvel has been bringing that love to 6 00:00:19,079 --> 00:00:23,400 Speaker 1: a wider audience with its cinematic universe. So today let's 7 00:00:23,440 --> 00:00:26,440 Speaker 1: get geeky with a deep look into how Captain America's 8 00:00:26,520 --> 00:00:30,080 Speaker 1: signature shield would work if it, you know, really existed. 9 00:00:34,760 --> 00:00:38,519 Speaker 1: Hey brain Stuff, I'm Christian Sager. The official Marvel Comics 10 00:00:38,600 --> 00:00:41,920 Speaker 1: database says that Captain America's shield is a metal disc 11 00:00:42,240 --> 00:00:45,840 Speaker 1: that's approximately two point five feet in diameter and weighs 12 00:00:45,880 --> 00:00:49,640 Speaker 1: twelve pounds, but Rhet Elaine at Wired Magazine did some 13 00:00:49,720 --> 00:00:52,240 Speaker 1: math and figured out that it would be more likely 14 00:00:52,320 --> 00:00:56,680 Speaker 1: to weigh forty three point nine pounds, despite the shield 15 00:00:56,720 --> 00:00:59,960 Speaker 1: being made of a unique alloy combining vibranium, which is 16 00:01:00,280 --> 00:01:05,160 Speaker 1: a fictional metal, steel, and an unknown third component. Elaine 17 00:01:05,200 --> 00:01:07,840 Speaker 1: also figured out that the density of the shield would 18 00:01:07,840 --> 00:01:11,240 Speaker 1: be somewhere between eight thousand, seven hundred and sixty seven 19 00:01:11,480 --> 00:01:15,920 Speaker 1: and four thousand, three eighty three kilograms per meter cubed 20 00:01:16,520 --> 00:01:21,240 Speaker 1: that is somewhere between the density of iron and titanium. Now, 21 00:01:21,240 --> 00:01:23,640 Speaker 1: in the Captain America comics, the story goes that Dr 22 00:01:23,720 --> 00:01:28,119 Speaker 1: Myron McLean was attempting to replicate Hercules golden mace by 23 00:01:28,160 --> 00:01:32,480 Speaker 1: fusing vibranium with an experimental iron alloy. Some say it 24 00:01:32,520 --> 00:01:35,200 Speaker 1: was a steel alloy, but even McClain didn't know what 25 00:01:35,319 --> 00:01:38,840 Speaker 1: it was because he fell asleep when an unknown catalyst 26 00:01:38,959 --> 00:01:41,840 Speaker 1: was introduced to the process. He was never able to 27 00:01:41,920 --> 00:01:45,280 Speaker 1: duplicate the process, so the government painted the disk and 28 00:01:45,319 --> 00:01:48,480 Speaker 1: gave it to Captain America. But how would you forge 29 00:01:48,560 --> 00:01:51,960 Speaker 1: such a thing, especially since metallurgy is so complicated. Just 30 00:01:52,040 --> 00:01:56,000 Speaker 1: the forging temperature alone depends on the materials carbon content, 31 00:01:56,320 --> 00:02:01,480 Speaker 1: it's alloy composition, maximum plasticity, and the out of reduction required. 32 00:02:01,920 --> 00:02:06,360 Speaker 1: Was it heated by induction or by continuous fuel fired furnaces. 33 00:02:06,400 --> 00:02:09,280 Speaker 1: With a material this unique, you would have to carefully 34 00:02:09,280 --> 00:02:13,960 Speaker 1: control the heating process. Now, forgibility is how easy or 35 00:02:14,120 --> 00:02:19,480 Speaker 1: difficult a material resists deformation, And since Captain America's shield 36 00:02:19,520 --> 00:02:22,800 Speaker 1: is indestructible, it would have to be a very narrow 37 00:02:22,840 --> 00:02:26,360 Speaker 1: forging temperature range, meaning it could only be forged for 38 00:02:26,400 --> 00:02:31,359 Speaker 1: a short time after heating. With metallurgical factors like crystal structure, 39 00:02:31,480 --> 00:02:35,000 Speaker 1: chemical composition, and grain size at play, the only way 40 00:02:35,080 --> 00:02:38,760 Speaker 1: McClain could have diminished their influence would be by adding 41 00:02:38,800 --> 00:02:43,960 Speaker 1: alloying elements, possibly compounds that easily dissolve within the metal. 42 00:02:44,560 --> 00:02:47,079 Speaker 1: There are all types of elements that could have been introduced, 43 00:02:47,280 --> 00:02:50,520 Speaker 1: but it's likely that Captain America's shield was forged like 44 00:02:50,600 --> 00:02:54,040 Speaker 1: a super alloy. This is how metall are just referred 45 00:02:54,040 --> 00:02:59,040 Speaker 1: to iron based, nickel base and cobalt based alloys, specifically 46 00:02:59,080 --> 00:03:03,000 Speaker 1: the ones that offer very high strength at high temperatures. 47 00:03:03,040 --> 00:03:06,120 Speaker 1: These really high strength metals and iron based grades are 48 00:03:06,160 --> 00:03:09,200 Speaker 1: the least difficult ones to work with, so that would 49 00:03:09,240 --> 00:03:13,800 Speaker 1: narrow down McClain's experimental alloy to iron. Super alloys are 50 00:03:13,840 --> 00:03:16,800 Speaker 1: really difficult to forge because of their narrow temperature range. 51 00:03:17,240 --> 00:03:20,440 Speaker 1: You can't even use regular sizing presses and hammers on 52 00:03:20,520 --> 00:03:24,160 Speaker 1: them because they'll deform. They even wear down the tools 53 00:03:24,280 --> 00:03:29,440 Speaker 1: designed for forging them pretty easily. They're also extremely expensive, 54 00:03:29,560 --> 00:03:33,160 Speaker 1: like ten times the price of carbon steel. Sounds a 55 00:03:33,160 --> 00:03:36,160 Speaker 1: lot like Captain America's shield, right, But how do we 56 00:03:36,200 --> 00:03:39,800 Speaker 1: explain the shield's ability to absorb kinetic energy, supposedly from 57 00:03:39,840 --> 00:03:44,000 Speaker 1: the vibranium in the alloy. Usually materials absorb kinetic energy 58 00:03:44,040 --> 00:03:49,160 Speaker 1: through other mechanisms like plastic or elastic deformation or dynamic 59 00:03:49,160 --> 00:03:52,520 Speaker 1: fluid flow, but cap shield doesn't seem to be an 60 00:03:52,520 --> 00:03:57,640 Speaker 1: elastometric material, and it's not organic like polyurethane in the movies. 61 00:03:57,720 --> 00:04:01,640 Speaker 1: It actually seems to reflect vibration rather than absorb it, 62 00:04:02,000 --> 00:04:04,080 Speaker 1: like when Thor hits it with m Olner in that 63 00:04:04,200 --> 00:04:07,840 Speaker 1: first Avengers movie and the shock wave flattens a whole forest. 64 00:04:08,280 --> 00:04:12,120 Speaker 1: Perhaps that was because the shield reached its absorption limit. 65 00:04:12,720 --> 00:04:15,520 Speaker 1: Another thing that's tough to explain is how aerodynamic the 66 00:04:15,520 --> 00:04:19,520 Speaker 1: shield is. If it really weighed forty three point nine pounds, 67 00:04:19,800 --> 00:04:21,960 Speaker 1: it would be difficult to throw, even for a guy 68 00:04:22,080 --> 00:04:26,080 Speaker 1: in peak physical condition like Steve Rogers. In the comics, 69 00:04:26,279 --> 00:04:29,800 Speaker 1: Tony Stark actually puts electro magnets under the shield to 70 00:04:29,880 --> 00:04:33,880 Speaker 1: help control it in midflight, but Captain America later ditched 71 00:04:33,920 --> 00:04:38,000 Speaker 1: them because they upset the shields natural balance. It seems 72 00:04:38,040 --> 00:04:41,039 Speaker 1: like the soldier and the shield are made for each other. 73 00:04:47,040 --> 00:04:50,200 Speaker 1: Today's episode was written by Christian and produced by Tyler Klang. 74 00:04:50,720 --> 00:04:52,560 Speaker 1: For more on this and lots of other topics that 75 00:04:52,600 --> 00:04:56,800 Speaker 1: shout excelsior, visit how stuff works dot com. Brain Stuff 76 00:04:56,839 --> 00:04:59,040 Speaker 1: is a production of my heart Radio. For more podcasts 77 00:04:59,040 --> 00:05:00,920 Speaker 1: to my heart Radio is the i heart Radio app, 78 00:05:01,000 --> 00:05:03,560 Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows. 79 00:05:14,640 --> 00:05:14,680 Speaker 1: H