-
1 Chatelier, Henri Louis le
Biographical history of technology > Chatelier, Henri Louis le
-
2 Le Chatelier, Henri Louis
SUBJECT AREA: Metallurgy[br]b. 8 November 1850 Paris, Franced. 17 September 1926 Miribel-les-Echelle, France[br]French inventor of the rhodium—platinum thermocouple and the first practical optical pyrometer, and pioneer of physical metallurgy.[br]The son of a distinguished engineer, Le Chatelier entered the Ecole Polytechnique in 1869: after graduating in the Faculty of Mines, he was appointed Professor at the Ecole Supérieure des Mines in 1877. After assisting Deville with the purification of bauxite in unsuccessful attempts to obtain aluminium in useful quantities, Le Chatelier's work covered a wide range of topics and he gave much attention to the driving forces of chemical reactions. Between 1879 and 1882 he studied the mechanisms of explosions in mines, and his doctorate in 1882 was concerned with the chemistry and properties of hydraulic cements. The dehydration of such materials was studied by thermal analysis and dilatometry. Accurate temperature measurement was crucial and his work on the stability of thermocouples, begun in 1886, soon established the superiority of rhodium-platinum alloys for high-temperature measurement. The most stable combination, pure platinum coupled with a 10 per cent rhodium platinum positive limb, became known as Le Chatelier couple and was in general use throughout the industrial world until c. 1922. For applications where thermocouples could not be used, Le Chatelier also developed the first practical optical pyrometer. From hydraulic cements he moved on to refractory and other ceramic materials which were also studied by thermal analysis and dilatometry. By 1888 he was systematically applying such techniques to metals and alloys. Le Chatelier, together with Osmond, Worth, Genet and Charpy, was a leading member of that group of French investigators who established the new science of physical metallurgy between 1888 and 1900. Le Chatelier was determining the recalescence points in steels in 1888 and was among the first to study intermetallic compounds in a systematic manner. To facilitate such work he introduced the inverted microscope, upon which metallographers still depend for the routine examination of polished and etched metallurgical specimens under incident light. The principle of mobile equilibrium, developed independently by Le Chatelier in 1885 and F.Braun in 1886, stated that if one parameter in an equilibrium situation changed, the equilibrium point of the system would move in a direction which tended to reduce the effect of this change. This provided a useful qualitative working tool for the experimentalists, and was soon used with great effect by Haber in his work on the synthesis of ammonia.[br]Principal Honours and DistinctionsGrand Officier de la Légion d'honneur. Honorary Member of the Institute of Metals 1912. Iron and Steel Institute Bessemer Medal.Further ReadingF.Le Chatelier, 1969, Henri Le Chatelier.C.K.Burgess and H.L.Le Chatelier, The Measurement of High Temperature.ASDBiographical history of technology > Le Chatelier, Henri Louis
-
3 Metallurgy
См. также в других словарях:
Chatelier , Henri Louis Le — See Le Chatelier, Henri Louis … Scientists
Le Chatelier, Henri Louis — Le Chatelier , Henri Louis … Scientists
Le Chatelier , Henri Louis — (1850–1936) French chemist Le Chatelier was born in Paris, the son of the inspector general of mines for France. He himself began studying mining engineering, before becoming professor of chemistry at the School of Mines in 1877. He later became… … Scientists
Henri Louis Le Châtelier — Henry Le Chatelier Pour les articles homonymes, voir Le Chatelier. Henry Le Chatelier Henry Louis Le Chatelier (Paris le 8 … Wikipédia en Français
Henri Louis le Chatelier — Henry Le Chatelier Pour les articles homonymes, voir Le Chatelier. Henry Le Chatelier Henry Louis Le Chatelier (Paris le 8 … Wikipédia en Français
Le Châtelier, Henry-Louis — born Oct. 8, 1850, Paris, France died Sept. 17, 1936, Miribel les Échelles French chemist. A professor at the Collège de France and the Sorbonne, he is best known for the principle of Le Châtelier, which makes it possible to predict the effect… … Universalium
Louis — Louis, Joe * * * (as used in expressions) Henry Louis Aaron Louis Francis Cristillo Agassiz, (Jean) Louis (Rodolphe) Aragon, Louis Louis Andrieux Armstrong, Louis Barrault, Jean Louis Barthou, (Jean) Louis Barye, Antoine Louis Berger, Victor… … Enciclopedia Universal
Henri Le Chatelier — Henry Le Chatelier Pour les articles homonymes, voir Le Chatelier. Henry Le Chatelier Henry Louis Le Chatelier (Paris le 8 … Wikipédia en Français
louis — /looh ee/; Fr. /lwee/, n., pl. louis /looh eez/; Fr. /lwee/. See louis d or. [1680 90] * * * (as used in expressions) Henry Louis Aaron Agassiz Jean Louis Rodolphe Aragon Louis Louis Andrieux Armstrong Louis Barrault Jean Louis Barthou Jean Louis … Universalium
Louis — /looh is/ or, for 2, /looh ee/, n. 1. Joe (Joseph Louis Barrow), 1914 81, U.S. boxer: world heavyweight champion 1937 49. 2. a male given name: from a Germanic word meaning loud battle. * * * (as used in expressions) Henry Louis Aaron Agassiz… … Universalium
Louis Massignon — (July 25 1883–October 31 1962) was a French scholar of Islam and its history. Although a Catholic himself, he tried to understand Islam from within and thus had a great influence on the way Islam was seen in the West; among other things, he paved … Wikipedia