1 mo (1 ~ 5) in history in
1.1 Mo discovery process "
Under natural conditions, there is no metal speciation of molybdenum, and mainlymolybdenite are distributed in the form of nature, the average crustal abundanceof 1.3 mg/kg. In eighteenth Century the galena is called molyldena, they haveroughly the same shape and density of Molybdenite mistaken for galena. In 1778,the Swedish scientist Carle. William. Scheele (Carl Wilhelm Scheele) get molybdic acid decomposition of Molybdenite by nitric acid, and obtained the molybdenum salt, the same year the molybdenum oxide, molybdenum are confirmed, and borrows the misunderstanding will be named molybdos. In 1782, Scheele'scompatriot Peter. Jacob. Hjelm (Peter Jacob Hjelm) with linseed oil adjusted the confined mixture burning charcoal and molybdate successfully restored the oxide,a black metal powder, and the metal powder as "Mo", molybdenum. In 1893, the German chemist M. Moissan with a mixture of electric heating carbon and twomolybdenum oxide, molybdenum content in the obtained 92% ~ 96% of the cast metal molybdenum. At the beginning of twentieth Century, Biel Qi Julius by hydrogen reduction of molybdenum trioxide obtained the metal molybdenum more pure.
The development history of 1.2 molybdenum
Although the eighteenth Century molybdenum is found, but very earlyapplication, such as in a fourteenth Century Japanese Wu Jianzhong foundcontaining molybdenum. The Mo easy oxidation, high brittleness, coupled with the twentieth Century molybdenum smelting and processing level is limited,mechanical processing of molybdenum has been unable, in the industry can not be a large number of applications, with only some molybdenum compounds, such as ammonium molybdate, as phosphorus reagents for use as a pigment using molybdenum blue and certain other compounds. In 1891, France's Snyder Schneider) the company will take the lead in molybdenum as an alloying elementproduction of molybdenum containing armor plate, found that its performance is superior, and the density of molybdenum tungsten is only 1/2, can effectivelyreplace tungsten in the field of application of many steel alloys of molybdenum,thus beginning the molybdenum industrial application. In 1900, successfullydeveloped the ferromolybdenum production process, also found thatmolybdenum steel can meet the special properties of steel materials to beprocessed, the rapid development of steel production in 1910. Since then,become the important component of various structure of molybdenum steel heat resistant and anticorrosive, is also an important component of non-ferrous metalalloy of nickel and chromium.
Molybdenum industry and is widely used in electrical industry, is about andtungsten metal at the same time (1909) began. Because of powder metallurgy and processing of production of these two kinds of dense metal have been successfully, can be applied to production. Another reason is the outbreak of the first World War, led to a surge in demand and supply of tungsten ferrotungstenextreme tension, which replaces the tungsten molybdenum in many highhardness and impact resistant steel. The results of molybdenum demand growthcontributed to the further research on molybdenum. At this time, AmericanColorado's large-scale mining clay Max (Climax) with the development of mine,and put into operation in 1918.
The end of the first World War led to a collapse in demand for molybdenum, to solve this problem is development of molybdenum in the new application ofcivilian industry, soon to many new low molybdenum alloy steel for automobile industry is tested and approved by. 30's reached such a point of view, the forging and heat treatment of molybdenum based high speed steel must request the appropriate temperature, put forward this view is a breakthrough technology.Since then, as the development of alloying elements in steel and other fields have entered a new stage of molybdenum. In twentieth Century 30 time end,molybdenum is widely used in industrial raw materials. 1945 the end of the second world war once again to stimulate the development and application ofmolybdenum in the civilian industry, coupled with the post-war reconstruction for many molybdenum containing tool steel application opens up broad market.During the Second World War, the vacuum arc melting method of clay Maxmolybdenum industry company American. To use this method to get the weight of 450 ~ 1000 kg Mo ingot, and made use of Mo as structural materials for road.Powder metallurgy development has been able to produce blank weight above 180 kg in the 50's.. After 50 years, the research work of molybdenum is the maincomposition and production process and actively explore the heat resisting Mobased alloy. Now, molybdenum material of high purification, nano composite, is the main research orientation.
