Properties of Rhenium

Rhenium is a silvery-white heavy metal with a melting point of 3180℃,boiling point 5600℃ and density 21.02g/cm3. Rhenium is stable at room temperature and starting to be oxidized when temperature reached 300℃. Rhenium and sulfur vapor will synthesize into rhenium disulfide and halide with fluorine, chlorine, bromine. The chemical properties of Rhenium depending on its aggregation and rhenium powder is more lively. The oxidation state of Rhenium including -1,+1,+2,+3,+4,+5,+6 and +7 valence. The oxides of Rhenium are Re2O、Re2O3、ReO2、ReO3、Re2O7.

Rhenium is very rare in earth’s crust,it’s usually associated with molybdenum and copper ores, it also can be found in uranium. Until 1930,the world’s total output of rhenium is only 3 grams. Even now,the world’s total annual output of rhenium is only dozens of tons,much less than the other metals.

Rhenium is a high melting point metal whose melting point is second only to tungsten.The chemical properties of Rhenium is stable and it has a strong corrosion resistance. It is not oxidized in the air, acid and alkali has a very little corrosion effect on it. Rhenium has an extremely high mechanical strength, a rhenium alloy wire thinner than human hair can withstand more than 7 kilogram of gravity. Rhenium also has very good wear resistance and corrosion resistance characteristics, its wear resistance is second only to metal osmium.Besides, rhenium also has high resistance and other electrical characteristics.

Rhenium has no brittle critical transition temperature and has good creep resistance under high temperature and rapid cooling and heating conditions.

In the metallurgical industry,adding a small amount of rhenium into certain alloys can greatly improve the properties of alloys, a phenomenon which known as the rhenium effect.