The density of molybdenum is 10.2 g/cc. Melting point is 2610 ℃. The boiling point of 5560 ℃. Molybdenum powder is pressed into green billet by isostatic pressure and sintered at about 2100 ℃, and hot processed at 870 ~ 1260 ℃. Molybdenum alloy sheet, strip, foil, pipe, bar, wire and profile can be produced by plastic processing. The strength and low temperature plasticity can be improved by adding different raw materials.

Molybdenum is also chemically stable and will not be corroded by hydrochloric, hydrofluoric, or alkaline solutions, but will be corroded by nitric acid, aqua regia, or hot concentrated sulfuric acid. Molybdenum is also an important additive element. At high temperature, molybdenum can effectively accelerate solid strengthening, prevent chloride pitting, and improve the anticorrosion performance in reducing liquid.

The high demand for oil has forced accelerated production of the AISI 4100 series CR-Mo steels containing 0.15% to 0.25% molybdenum, which are often contaminated by corrosive hydrogen disulfide, carbon dioxide and highly chlorinated brine on land and offshore. The modified 4140 series containing 0.4% to 0.6% molybdenum is the most resistant low-alloy steel to sulphide stress erosion (SCC) and can be used in sulphide Wells.

The use of stainless steel and nickel-based alloys with higher molybdenum content, such as alloys C-22 (13% Mo) and C-276 (16% Mo), will increase as drilling depth increases and service conditions deteriorate. Stainless steel is corrosion resistant because chromium naturally forms a thin protective passivation film on the surface of the steel. Molybdenum actually makes the passivated film stronger and allows rapid regeneration of the passivated film when it is destroyed by chloride. The increase of molybdenum content can improve the corrosion resistance of pitting and cracking of stainless steel. Type 316 (2% ~ 3% Mo) is the most widely used stainless steel containing molybdenum. It is designated as a tank, pipe and heat exchange material for food processing and processing as well as pharmaceutical production. Increased molybdenum content increases resistance to airborne chlorides, so type 316 can also be used as a material of choice for large amounts of offshore and coastal use.

Molybdenum forms volatile oxides when exposed to air at temperatures above approximately 600 ℃, so high temperature applications of molybdenum are best in inert gas protection or vacuum environments. http://www.youyouwudao.com