Application of Rhenium

With the various of excellent properties, Rhenium has become an important material used in many fields. More than 60 percent of global production of rhenium is used to make superalloy parts for jet engines. Another major application of rhenium is in platinum-rhenium catalysts, which can be used to produce unleaded, high-octane gasoline.

Superalloys: adding rhenium will increase the creep strength of nickel superalloy. Nickel-based rhenium alloys generally contain 3% to 6% rhenium. The rhenium content of the second generation alloy is 3% and was used in F-16 and F-15 fighter engines. The third generation single crystal alloy contains 6% rhenium. And was used in F-22 and F-35 engines. Rhenium superalloy is also used in industrial gas turbines. The superalloy will form a topological close packed phase (TCP)after adding rhenium, therefore its microstructure will become unstable. The fourth and fifth generation superalloys will use ruthenium to avoid this phenomenon.

Other rhenium alloys: pure tungsten and pure molybdenum will become fragile as glass at low temperature condition and hard to process,therefore its use is limited. But tungsten rhenium alloy or molybdenum rhenium alloy made by adding an appropriate amount of rhenium to tungsten or molybdenum has good plasticity,it can be processed into a variety of structural materials, while maintaining high hardness, high strength and high temperature resistance. Many parts of the U.S. manned spacecraft are made of this kind of rhenium alloy. Adding a small amount of rhenium in chromium nickel alloy can greatly improve the melting point and strength of the alloy. The service life of parts made of this alloy can be extended several to tens of times.

The use of rhenium in industrial temperature measurement, semiconductor, catalyst, nuclear industry and other fields is also eye-catching. With good chemical property,tungsten rhenium alloy wire can be used in high temperature tungsten rhenium thermocouple and as cathode filament.Used in vacuum, hydrogen, and inert atmosphere,the use temperature range of tungsten rhenium thermocouple wire is 0~2300℃. Due to the low vapor pressure and high resistance of rhenium, it has good dimensional stability when used in resistance heating and can achieve high heating efficiency,and the surface load is relatively high. The core resistance heater of the semiconductor MOCVD equipment is also made of rhenium material.

Besides,a processed product of rhenium--rhenium ribbon which can be used as a filament on a thermoelectric ionization mass spectrometer in the atomic and nuclear industry.

Catalyst: rhenium-platinum alloy is a catalyst in the catalytic reforming process.This petroleum processing can increase the octane number of naphtha. 30% of the catalysts used in catalytic reforming contains rhenium. Coating rhenium on the surface of bauxite (alumina) can be used as a catalyst for olefin metathesis reaction. Rhenium-containing catalysts can resist the poisoning of nitrogen, sulfur and phosphorus catalysts, they are used in certain hydrogenation reactions.

In a word,with the development of material science, rhenium and its alloys have been used more and more widely .