Rhenium is a silvery metal which is usually obtained as grey powder. It is one of the last naturally occurring element to be discovered . Re is known for its high melting point 3,180℃,boiling point 5,600℃ and density 21.02 g /cm³.
　　One of the key reasons why rhenium is so important today is that rhenium has a rather unique property. Rhenium has no known ductile to brittle transition temperature unlike molybdenum and tungsten even after complete recrystallization annealing. Products from rhenium can be thermally cycled thousands of times with no ill effect. It can be alloyed with tungsten or molybdenum and, near the solubility limits, imparts improved ductility to those materials. High-temperature strength, low friction, ductility... More