Word: tungsten
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Dates: during 1940-1949
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...infinitesimal sub-atomic particles. They are similar to radium rays and they work in exactly the same way to destroy living cells. They are created when a powerful electric current-i.e., a stream of electrons -jumps through a vacuum tube and hits a "target,", usually a piece of tungsten. The electrons batter from the tungsten a secondary stream of chargeless particles, X-rays, whose wave lengths are thousands of times shorter than those of ultraviolet light and almost as short as those of radium's gamma rays. The shorter waves are the farther they penetrate into matter before...
...refined copper, wants back only about 6% of the U.S. supply. It furnishes 25% of U.S. zinc, wants 8%. Of lead it supplies 25%, wants 9%. It has been getting about one-fifth of its needs in these materials. It supplies the U.S. with raw aluminum, mercury, tungsten and antimony, but can get none back in manufactures...
...Welding electrodes which combine the high electrical conductivity of silver or copper with the heat resistance of tungsten, molybdenum or nickel...
Germany's contribution to powder metallurgy came about 1916 when the great Krupp Works learned from the electrical industry to press and sinter mixtures of tungsten carbide with cobalt into the hardest cutting compound known, began producing it commercially. These hard-cemented carbides have a hardness between diamond and sapphire. They are often shaped into cutting tools by another product of powder metallurgy: a solidified mixture of diamond dust and bronze powder. They work without softening at high, cherry-red heats while cutting ordinary armament steels two to ten times faster than cutting tools made of the toughest high...
...from the Door Latch. About 1922 the U.S. electrical industry created a byproduct of its work with tungsten: bearings pressed from copper and iron alloys. Their sponginess was their advantage: the fine continuous pores (up to 40% by volume) can absorb oil, exude it by capillary action as needed. Often they require no further oiling after impregnation; they can be sealed into machinery (e.g., household refrigerators) and forgotten. By 1932 "oil-less" bearings were used for many purposes in automobiles and were in time found to outlive the rest of the machine. Billions of such bearings...