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Get ready for the Amorphous Age.
The history of metalworking provides a good overview of technological development. In fact, eras are often named after the metal most prevalent at the time.
This began in the Bronze Age. Bronze was the metal of choice for everything from wine jugs to weapons and armour. It was very versatile.
The next revolution came in the Iron Age. Iron is considerably harder to work with than bronze, but it has the advantage that it is not as soft. Cast iron is still very heavy and it is brittle as well.
In 1856 steel made its first appearance. Invented by Henry Bessemer, the word steel refers to an entire family of metals, all alloys in which iron is mixed with carbon and other materials. It’s minor disadvantages are outweighed by the fact that steel is incredibly strong.
Strong it may be, but there are materials under development right now that makes steel look like tissue paper. Called glassy metal (or sometimes amorphous metal), descriptions of this material sound like something out of science fiction.
Glassy metals are nothing less than an entirely new class of materials. They can be used to build lighter and stronger versions of absolutely anything, including body panels and other parts.
The main virtue of glassy metals is their strength. A strip of amorphous metal thinner than a dime simply cannot be cut with hand tools. How is a material with that sort of strength made?
The term glassy metal gives an important clue. When molten, both glass and metals exist in an amorphous state, with their atoms jumbled up.
When metal cools, its atoms rapidly form into a lattice of crystals. It is this crystallization that makes regular metal break, dent and rust, caused by defects in which the crystals are pushed out of alignment. In order to make a glassy metal, you have to find a way to frustrate that crystallization.
Glassy metals first made an appearance in the early 1950s. By cooling vapourized tin and lead extremely rapidly, scientists were able to make a metallic material with some of the properties of glass. These were roughly 1/100th the thickness of aluminum foil. Not very useful for practical applications.
By 1990 researchers in Japan found they could make metallic glass by using three or more elements. To do this, the atoms of the elements have to differ in size by at least 12 per cent. Basically, when an alloy like this cools, the atoms don’t know where to go to form crystals.
Work is still being done on glassy metals. The main barrier right now is money. Amorphous steel has a cost roughly 60 times that of regular steel.
However, once this is overcome, glassy metals will change both manufacturing and the repair process forever.
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