Aluminum was only identified as a unique element in The first part of the system most commonly used today is called the Bayer process, named after Austrian chemist Karl Bayer, who invented it in The Bayer Process: Bauxite is mined and crushed, then mixed with water and lye, and heated in tanks. This heat and lye cause the alumina in the ore to dissolve in the water, while impurities sink to the bottom.
The alumina-rich water is then siphoned off and filtered to remove further impurities, and then pumped into huge precipitation tanks, where the water is allowed to precipitate away. The crystals are washed and allowed to dry. So a powerful electric current is sent through the molten material—and that causes the bonds to break.
The oxygen is released as gas, and is attracted to carbon rods suspended above the molten mix, where it bonds with carbon to form CO2 gas just like in the iron smelting process.
The freed-up aluminum melts and collects at the bottom of the pot. At this point it is Aluminum is used in a wide variety of applications, in its pure form aluminum foil is made from nearly pure aluminum , and more commonly in alloys, mixed with elements such as silicon, copper, and zinc.
Some are stronger than steel, and have the added benefit of being much lighter. Common uses include in cookware, soft drink cans, and automobile engine blocks. More than 90 percent of the platinum mined in the world today comes from just four sites: three in Russia and one in South Africa. Production is quite complicated. More than ten tons of ore must be mined to make a single ounce of platinum. A brief description of the process is as follows:.
H, He, and dark matter? But I see your point. The metal in the ring on my finger is older than the planet…. The calcium, nitrogen, oxygen, iron, carbon, sodium, etc are also from some ancient star. And the hydrogen is even older than that. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment.
Enjoy this article? Articles Science. Drew November 13, pm. Hence, like silver and gold, they used copper to make ornaments and decorative items. 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. One will find bits of copper metal in smart phones, computer chips, large industrial motors, digital cameras, and industrial transformers.
Furthermore, copper is also used in heating systems, electrical, and electronic equipments. Carnegie began his ascent as a teenage messenger boy in a telegraph office.
One day, a high-ranking official at the Pennsylvania Railroad Company, impressed by the hardworking teen, hired Carnegie to be his personal secretary. He owned stakes in a bridge-building company, a rail factory, a locomotive works, and an iron mill. When the Confederacy surrendered in , the year-old Carnegie turned his attention to building bridges. Thanks to his mill, he had the mass production of cast iron at his disposal. But Carnegie knew he could do better than cast iron.
A durable bridge needed steel. About a decade before Sidney Thomas refined the Bessemer Converter with a lime-based lining, Carnegie brought the Bessemer process to America and acquired phosphorus-free iron to produce steel. By this point, Carnegie was single-handedly producing about half as much steel as all of Britain. Additional steel companies started sprouting up around the country, creating new towns and cities, including an iron mining town in Connecticut named " Chalybes " after the ironmakers of antiquity.
America was suddenly steamrolling its way to the top of the steel industry. To keep manufacturing costs down, wages were low. In July , tensions boiled over between the Carnegie Steel Company and the union representing workers at the Homestead mill.
The company chair, Henry Clay Frick, took a hard stance, threatening to cut wages. The workers hanged an effigy of Frick, and he responded by surrounding the mill with three miles of barbed-wire fence, expecting hostilities. About 3, strikers took control of Homestead, forcing out local law enforcement. Frick hired agents from the Pinkerton Detective Agency to guard the mill, and on the morning of July 6, , a civil battle ensued.
Men gathered at the riverbank, throwing rocks and firing guns at the Pinkerton agents trying to get ashore in boats. The strikers used whatever they could find as weapons, rolling out an old cannon, igniting dynamite, and even pushing a burning train car into the boats.
Order was restored when a National Guard battalion of 8, entered the town and placed Homestead under martial law. Ten people were killed in the clash. Frick was later shot and stabbed in his office by an anarchist who heard of the strike, but survived. He left the company shortly after, and in , Carnegie hired an engineer named Charles M.
Schwab not to be confused with the founder of the Charles Schwab Corporation to serve as the new president. The American steel industry continued to explode into the 20th century. In , the United States produced , tons of steel. By , America accounted for It was a rate of production never before seen across the globe, but the steel foundries were just getting warmed up.
Disagreements at U. Steel led Charles Schwab to find a new job presiding over a different, rapidly growing company: Bethlehem Steel. Hours later, he bought a ticket to cross the Atlantic under a false name. Schwab accepted and went to his next meeting, this one with the First Lord of the Admiralty, Winston Churchill. Churchill placed an order of his own: submarines for the Royal Navy to combat German U-boats, and he needed them immediately.
But Schwab had a problem. Neutrality laws in the U. Undeterred, Bethlehem Steel sent submarine parts to an assembling plant in Montreal ostensibly for humanitarian rebuilding efforts—and American steel started leaking into the Allied war effort.
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.
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