• Molybdenum: history and industry development

• History

• In ancient times a number of substances were collectively known by the Greek word "molybdos", meaning lead-like. Molybdenite (MoS2), the most abundant molybdenum-containing mineral, was in this class along with lead, galena, graphite and others. Because at that time people did not distinguish between these various compounds, molybdenite was often confused and used as graphite to blacken a surface or as a solid lubricant. Although people used molybdenum as an alloying element to produce the blade of 14th-century Japanese swords, that art was never employed widely and was later lost.
• In the West in 1754, Bengt Andersson Qvist examined molybdenite and found that it did not contain lead, and thus was not the same as galena. In 1768, the Swedish scientist Carl Wilhelm Scheele determined that molybdenite was a sulfide compound of an as-yet unidentified element, by decomposing it in hot nitric acid and heating the product in air to yield a white oxide powder. In 1782, at Scheele’s suggestion, Peter Jacob Hjelm chemically reduced the oxide with carbon, obtaining a dark metal powder that he named “molybdenum”.

• Industry development

• Due to its relative scarcity, the difficulty of extracting the pure metal, and the lack of appropriate metallurgical techniques, molybdenum was mainly a laboratory curiosity and had no industrial use until the late 19th century when technology for the extraction of commercial quantities became practical. Experiments with steel showed that molybdenum could increase the hardness of steel alloys and could also effectively replace tungsten in many steel alloys. This change brought weight benefits, because the atomic weight of molybdenum is nearly half that of tungsten. In 1891, the French company Schneider & Co. first used molybdenum as an alloying element in armor plate steel.
• In 1913, Frank E. Elmore developed a flotation process to extract molybdenite from ores. During World War I, the demand for alloy steels caused tungsten demand to rise sharply, severely constraining its supply. Molybdenum gradually replaced tungsten in many hard and impact-resistant tungsten steels because of the tungsten shortage. This increase in molybdenum demand motivated people to search for new sources of supply. Finally, the massive Climax deposit in Colorado, USA was found and people began to exploit it in 1918.
• After the war, demand for alloy steels dropped sharply, people began to study new civilian applications for molybdenum, and several new low-alloy molybdenum automotive steels were soon tested and accepted. In the 1930s, researchers found the proper temperature ranges to forge and heat-treat molybdenum-bearing high-speed steels, a breakthrough that opened large new markets for molybdenum. By the end of the 1930s, molybdenum had become a widely accepted technical material.
• In World War II, molybdenum again saw strategic importance as a substitute for tungsten in steel alloys, thus its demand increased again. After World War II, people once again increased research investment to develop new civilian applications, and the post-war reconstruction also provided additional markets for molybdenum-containing structural steels.
• Nowadays, in addition to alloys, molybdenum is also widely used in many other products, such as chemicals, electrical products, fertilizers and so on. And global molybdenum production and consumption have also increased greatly.