Real Engineering
Уровень B2· 856 слов
This was one of the first devices in the world to make use of a new wonder material. Like too often, it's a weapon.
Its casing made from a new magnesium alloy developed in Germany in 1908, dubbed Elektron. Magnesium in its pure form is a tremendously light, shiny metal that rapidly corrodes. It isn't particularly strong, and when ignited, it is incredibly hard to put out. This highly reactive material burns so hot and
aggressively that all three of these fire extinguishers can actually make fires worse. When sprayed with water, the burning magnesium rips the hydrogen and oxygen apart, providing an explosive atmosphere for itself. When sprayed with carbon dioxide, it rips the oxygen off carbon.
Incredibly attractive as a fuel source in a bomb, but not as a structural casing. The Germans had formulated this alloy to address those problems. It was 9% by weight aluminum. They didn't fully understand why this made magnesium so much stronger, but this made the magnesium strong enough to be used in
lightweight structural parts in planes and zeppelins of World War I. The war ended before this monstrous little bomb could be used for its intended targets, Paris and London.
Just 1 kg in weight, thanks to its innovative casing, a single German bomber aircraft could carry hundreds of them.
These tiny bombs were filled with thermite, which burned hot enough to ignite the magnesium metal casing.
Similar bombs were used by the British when they attacked civilians in Dresden. When this bomb cracked through the roofs of the buildings below, it would ignite everything in sight. The goal, to overwhelm the enemy cities fire departments. This horrible weapon of terror finally got its target during the
Spanish Civil War, when the Germans used it to lay waste to the Basque stronghold of Guernica, inspiring the great anti-war painting by Pablo Picasso, Guernica. [music] And yet, for all of its terrible uses, today, magnesium alloys have evolved.
Gradually being adapted and improved, being used in World War aircraft engines, and entering the commercial market with lightweight custom mag wheels. Today, it's being used in the casing of high-performance electric motors. I interviewed Seth Hawthorne, the design system engineer for Corvette's hybrid electric E-Ray.
>> Yep, so we have magnesium case, so we did that really because of mass savings. Um this is uh we worked with a supplier who has proprietary information over this. But we even had what we started with theirs and we had it tweaked even further. And in terms of doing that, we wanted to get the
the strength that we needed for the the unit. Um obviously mass was another big savings. Uh but durability. So, we didn't want to just have it too soft cuz if you have this that's too soft, you'll end up getting bending frequencies inside there. You'll get gear scuffing, bad things happening there. So, we had to