I Tried Railroad Thermite Welding

How Thermite turned the clickety-clack of railroads into seamless, silent tracks. Get an exclusive 15% discount on Saily data plans! Use code veritasium at checkout. Download Saily app or go to https://saily.com/veritasium A massive thank you to everyone at Goldschmidt for making this possible. With special thanks to Dr. Axel Hoeschen, Christof Gassmann and Claudia Koch. If you want to learn all the details about why we don’t need expansion joints anymore, check out Grady’s excellent video here: youtu.be/zqmOSMAtadc If you’re looking for a molecular modeling kit, try Snatoms, a kit I invented where the atoms snap together magnetically. https://snatoms.com/ ▀▀▀ 00:00 The problem with continuous welded rail 03:33 How to weld two rails together 10:16 Why is rapidly cooled steel brittle? 11:40 Thermite reaction and a see-through mold 16:30 Clean up 19:11 Metallurgy 22:15 How strong is the weld? 24:26 Why don’t the rails buckle? ▀▀▀ References: Practical Engineering. Why Railroads Don't Need Expansion Joints youtu.be/zqmOSMAtadc Stress–strain curve In Wikipedia - https://ve42.co/stressstrain The Efficient Engineer. Understanding Metals via Youtube https://youtu.be/PaGJwOPg2kU moodlemech. Properties and Grain Structure via Youtube - youtu.be/uG35D_euM-0 Images & Video: bhadeshi123. Martensitic transformation via Youtube youtu.be/OQ5lVjYssko Stratford Works In Wikipedia - https://ve42.co/stratford Electric Tram 1881 In Wikipedia - https://ve42.co/tram Water Quenched Steel In Wikipedia - https://ve42.co/quench Synagoge 1922 In Wikipedia - https://ve42.co/synagoge ▀▀▀ Special thanks to our Patreon supporters! Join the community to help us keep our videos free, forever: https://ve42.co/PatreonDE Alexander Tamas, Autodidactic Studios, Farbod Mansorian, Gnare, Juan Benet, Lee Redden, Meekay, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Ubiquity Ventures, Adam Foreman, Albert Wenger, Anton Ragin, Bertrand Serlet, Blake Byers, Bruce, Dave Kircher, David Johnston, Evgeny Skvortsov, Garrett Mueller, gpoly, Greg Scopel, I. H., KeyWestr, Kyi, Marinus Kuivenhoven, Matthias Wrobel, meg noah, Michael Krugman, Spilmann Reed, Tj Steyn, TTST, wolfee. ▀▀▀ Directed by Derek Muller and Casper Mebius Written by Derek Muller and Casper Mebius Edited by Trenton Oliver Animated by Mike Radjabov, Rokas Vikšraitis and Fabio Albertelli Filmed by Derek Muller, David Bochmann, Casper Mebius, Luise Dietert, Henning Fischer and Harald Schweiger Additional research by Geeta Thakur Produced by Derek Muller, Casper Mebius, Gregor Čavlović, Geeta Thakur, Rob Beasley Spence, Emily Lazard and Tori Brittain Thumbnail contributions by Peter Sheppard and Ren Hurley Additional video/photos supplied by Getty Images and Story Blocks Music from Epidemic Sound


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