This material was isolated by P.J. Hjelm in 1781 at Uppsala, Sweden. The principal ore is molybdenite, purified, heated to MoO3 and reduced to Mo with hydrogen. The metal structure is bcc.
It is a lustrous silvery metal usually obtained as a grey powder. Molybdenum metal combines with oxygen at red heat and slowly assumes a blue patina in air.
It is attacked slowly by acids such as HNO3 and HF. It is used in alloys, electrodes and catalysts. When above 500°C it is necessary to exclude air from molybdenum to prevent formation of the oxide, which does not form a protective layer. The rate of oxidation is proportional to temperature and is very rapid above 1000°C.
Molybdenum in higher quantities up to 5% is present in almost all high speed tool steels, where hardness is necessary. The fact that molybdenum forms stable hard carbides with available carbon accounts for these qualities and the increased creep strength of nickel chromium molybdenum steel.
Relative Atomic Mass
In Soviet times Russia was a regular importer of Western produced Ferro Molybdenum, and Molybdenum Trioxide for additions in the domestic steel industry.
Those times have largely passed. Today with the separation of the Soviet Union into its various entities, Mongolia exports Molybdenum Sulphide Concentrates direct to the West or sends material to Chelyabinsk for conversion into Ferro Molybdenum for export.
Armenia sends Rhenium-bearing Moly concs abroad for conversion and Kazakhstan converts less Molybdenum bearing copper concentrates and rather imports non-Moly bearing raw materials for smelting. Lipmann Walton’s interest in Molybdenum is in the metal rather than the Ferro Alloy or the Concentrate. We have interest to buy Molybdenum Fully Sintered Metal Bars described as typically Mo 99.8% min, W 0.2% max. We can accept bars which usually have a 20mm cross section and 1000m length, as well as slabs or electrodes. We can also accept punchings, sheet and wire, although hair wire commands a heavy discount. We would be grateful if the supplier can advise details of form if other than bar & supply a full chemical analysis as well as full description of surface condition and whether the material is clean or oxidised.