Aleksandar Just (1872-1937) was a physicist and inventor who, with Croatian Franjo Hannaman, in 1904 was the first to develop and patent an electric bulb with a Tungsten filament, made by extruding a paste of tungsten powder and a carbonaceous binder, to produce a fine thread, then removing the carbon by heating in an atmosphere of hydrogen and water vapor.[1] It received a Hungarian patent in 1904 and later US Patent 1,018,502. In 1905, Just and Hanaman patented a process for producing tungsten filaments with by plating carbon filaments tungsten, then removing the carbon by heating.[2] These early tungsten lamps was more efficient than a carbon filament lamp, because it could operate at a high temperature, due to the high melting point of tungsten, but because the tungsten was not ductile, it was so brittle as to be of limited practical use.[3] It was supplanted by the drawn tungsten filament lamp, developed in 1910 by William David Coolidge.
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