The development of civilisation has relied heavily on the discovery of metals. At Makin Metal Powders we supply a range of metal powders and decided to highlight the discovery of all known metals in a graphical timeline there is a text version below - please share it and let us know what you think.
Few artifacts or ruins remain from the period, which lasted roughly years. Classical Greece was an era of cultural achievements including the Parthenon , Greek drama and philosophers including Socrates. During the Iron Age in the Near East, nomadic pastoralists who raised sheep, goats and cattle on the Iranian plateau began to develop a state that would become known as Persia.
The Persians established their empire at a time after humans had learned to make steel. Steel weapons were sharper and stronger than earlier bronze or stone weapons. The ancient Persians also fought on horseback. They may have been the first civilization to develop an armored cavalry in which horses and riders were completely covered in steel armor. Celts lived across most of Europe during the Iron Age.
The Celts were a collection of tribes with origins in central Europe. They lived in small communities or clans and shared a similar language, religious beliefs, traditions and culture. Their legacy remains prominent in Ireland and Great Britain, where traces of their language and culture are still prominent today. People throughout much of Celtic Europe lived in hill forts during the Iron Age. Walls and ditches surrounded the forts, and warriors defended hill forts against attacks by rival clans.
Inside the hill forts, families lived in simple, round houses made of mud and wood with thatched roofs. They grew crops and kept livestock, including goats, sheep, pigs, cows and geese. Hundreds of bog bodies dating back to the Iron Age have been discovered across Northern Europe. Bog bodies are corpses that have been naturally mummified or preserved in peat bogs. The mysterious bog bodies appear to have at least one thing in common: They died brutal deaths. For instance, Lindow Man, found near Manchester, England, appears to have been hit over the head, had his throat slit and was whipped with a rope made of animal sinew before being thrown into the watery bog.
On the other hand, among the Egyptians, copper was a sacred metal. They believed that it gave magical powers to persons who wore it. Besides using copper to make artifacts, ancient civilizations also used copper for medical purposes. Around BC, ancient Egyptians used copper to heal wounds and sterilize water. In addition, copper eased pain caused by headaches.
It was also effective medicine for burns and itching. Among the Indians, copper was part of the surgical instruments used by doctors. Copper occurs naturally in the oceans, earth's crust, lakes, and rivers. In , when the war was just getting started, the United States produced American steel gave the Allies a decisive advantage in the fight against the Central Powers. When the war ended, U. Art Deco towers began to sprout up among the New York and Chicago skylines, with the vast majority of the steel coming from two companies: U.
Steel and Bethlehem Steel. Less than a year later, the Empire State Building, with 60, tons of steel supplied by U. Steel, would reach higher than Chrysler to become the enduring symbol of Manhattan. The material went into a bonanza of cars, home appliances, and food cans.
Bethlehem Steel and U. Following the stock market crash of , steel production slowed as the economy tumbled into the Great Depression.
American steelworkers were laid off, but the mills never went completely dark. Railroad tracks still spread across the country, canned food remained popular, and as Prohibition drew to a close, a new steel product emerged: the steel beer can, introduced in the s by Pabst for its Blue Ribbon brew. Following the Depression, the metal-hungry engines of war again ignited the foundries of the world.
Germany moved to occupy land in Denmark, Norway, and France, gaining control of new iron mines and mills. Suddenly, the Nazis were capable of producing as much steel as the United States. In the East, Japan took control of iron and coal mines in Manchuria. The industrialized nations of the world, hurtling headfirst into world war, began rationing steel for a select few purposes: ships, tanks, guns, and planes.
The American mills melted metal 24 hours a day, often with primarily female workforces. The economy began to boom again, and soon American steel production was more than three times larger than that of any other country. When the war was over at last, the U. Steel from leftover ships and tanks was melted down in enormous furnaces to be reused in bridges and beer cans.
But overseas, a dire need to rebuild, and the introduction of new steelmaking technology, was about to help foreign steel companies flourish. Even with mills churning non-stop during wartime, manufacturers had not yet perfected the art of smelting steel.
It would take an idea dreamed up years before the end of WWII to revolutionize the process once more—and ultimately, to dethrone the U. German scientist and glassmaker William Siemens, living in England to take advantage of what he believed to be favorable patent laws, realized in that he could lengthen the amount of time a furnace held its peak temperature by recycling the emitted heat.
Siemens built a new glass furnace with a small network of firebrick tubes. Hot gases from the melting chamber exited through the tubes, mixed with external air, and were recycled back inside the chamber. In the s, a French engineer named Pierre-Emile Martin learned of the design and built a Siemens furnace to smelt iron.
The recycled heat kept the metal liquefied for longer than the Bessemer process, giving workers more time to add the precise amounts of carbon-bearing iron alloys that turned the material to steel. And because of the additional heat, even scrap steel could be melted down. By the turn of the century, the Siemens-Martin process, also known as the open hearth process, had caught on all over the world. Jump forward to the 20th century, when a Swiss engineer named Robert Durrer found an even better way.
Durrer was teaching metallurgy in Nazi Germany. He blasted pure oxygen into the furnace rather than air, which is only 20 percent oxygen , and found that it removed carbon from the molten iron more effectively. Durrer also discovered that by blowing oxygen into the furnace from above, rather than below as on a Bessemer Converter, he could melt cold scrap steel into pig iron and recycle it back into the steelmaking process. The method combined the advantages of both the Bessemer and Siemens-Martin furnaces.
Thanks to Durrer's innovations, producing vast quantities of steel became cheaper yet again. While nations in Europe and Asia immediately adopted the basic oxygen process, American mills, still at the top of the industry, soldiered on using the Siemens-Martin process in confident contentment—unwittingly opening the door for foreign competition.
In , a British metallurgist named Harry Brearly was looking for a way to preserve the life of gun barrels. Experimenting with chromium and steel alloys, he found that steel with a layer of chromium was particularly resistant to acid and weathering. His friend, Ernest Stuart, who needed to sell the knives to the public, came up with a catchier name: stainless steel.
A company called Victoria was forging steel knives for the Swiss Army when it caught wind of the new anticorrosive metal from Great Britain. Today, there is a good chance you could find one of their red pocketknives in your desk drawer.
Suddenly stainless steel was all over the world. The anticorrosive, glimmering metal became a critical material for surgical tools and home goods. The hubcaps at the top of the Chrysler Building are made of stainless steel, which helps them retain their silver sheen in the sunlight.
In , workers broke ground in St. Louis to build the stainless steel Gateway Arch, which remains the tallest man-made monument in the Western Hemisphere. But just as St. Louis was building the Gateway to the West, the rest of the world was catching up with American steel production.
Low wages overseas and the use of the basic oxygen process made foreign steel cheaper than American steel by the s, just as the steel industry took a hit from a cheaper alloy for home goods: aluminum. In , U. As of , the United States ranked fourth in steel production according to the World Steel Association. These metalworks do not make steel from scratch, but rather melt down scrap steel for reuse.
The most common furnace in a mini mill—the electric arc furnace, also invented by William Siemens—uses carbon electrodes to create an electric charge to melt down metal. The spread of mini mills in the last half-century was a critical step toward recycling old steel, but there is a long way to go to achieve fully sustainable smelting. Forging steel is a well-known emitter of greenhouse gases. The basic oxygen process, still used widely today, was developed almost a century ago, when the ramifications of climate change were only just entering circles of scientific research.
The basic oxygen process still burns coal , emitting about four times more carbon dioxide than electric furnaces. But phasing out the oxygen blasts entirely for the electric arc is not a sustainable solution—only so much scrap steel is available for recycling.
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