Alexander Just Explained

Alexander Friedrich Just (12 April 1874, in Bremen – 30 May 1937, in Budapest) was an Austro-Hungarian chemist and inventor.[1] Later, in Hungary he used the name Just Sándor Frigyes. In 1904 with Austro-Hungarian Franjo Hanaman he was the first to develop and patent an incandescent light 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 vapors.[2] Just and Hanaman received a Hungarian patent in 1904, and later US Patent 1,018,502.[3] In 1905, Just and Hanaman patented a process for producing tungsten filaments by plating carbon filaments with tungsten, then removing the carbon by heating.[4] These early tungsten lamps were more efficient than a carbon filament lamp, because they could operate at a high temperature, due to the high melting point of tungsten. The tungsten was, however, so brittle that these lamps were of limited practical use.[5] It was supplanted by the drawn tungsten filament lamp, developed in 1910 by William David Coolidge.

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Notes and References

  1. Web site: Archived copy . 2012-10-23 . https://web.archive.org/web/20131111090715/http://theop11.chem.elte.hu/main_index_files/2012_BabayTanariSzakdolgozat.pdf . 2013-11-11 . dead .
  2. Coolidge. W. D.. Metallic Tungsten and Some of its Applications. Transactions of the American Institute of Electrical Engineers. XXXI. 1. 1912. 1220. 0096-3860. 10.1109/T-AIEE.1912.4768477. 51652033. https://books.google.com/books?id=YeAtAQAAIAAJ&q=hanaman&pg=PA1220
  3. US . 1018502 . patent . INCANDESCENT BODIEs FOR ELECTRIC LAMPS . 1912-02-27. "1905-07-06" . Just, Alexander . Hanaman, Franz .
  4. Hirst, H. "Recent progress in tungsten metallic filament lamps," The Electrical Journal, Volume LXI, May 22, 1908, pages 215-216. Retrieved December 14, 2011
  5. Day, Lance and McNeil, Ian "Biographical dictionary of the history of technology," Routledge, 1996. Cited edition is Taylor & Francis eBook, 2005, page 290. . Retrieved December 14, 2011.