Refractory Alloys Rhenium

One of rhenium's major uses is as a catalyst in the crack distillation of petroleum products. Another common use is as filaments in mass spectrometers. Rhenium is available in 99.97 (commercial) purity and 99.995 (zone refined) purity. These purity levels become most important in the mass spectrometer industry. Use for mass spectrometer filaments is a high demand area. These are normally stocked for quick delivery in purities of both commercial (99.97%) and zone-refined (99.995%) grades.

Molybdenum and tungsten normally have to be warmed up to their ductile/brittle transition temperatures before they can be formed. This is not true of rhenium. Pure rhenium sheet is produced using powder metallurgy techniques. Similar to tantalum, rhenium can be formed into a variety of shapes quite readily at room temperature.

Rhenium is not machinable by conventional methods such as turning, milling, etc. It can be ground and EDM machined. It can also be formed and welded. Rembar will advise you on the practicality of making a part out of rhenium and, if it can be made, Rembar can make it.

Rhenium has several unique properties that are also imparted to its alloys. One of the most important of these is its high melting point of 3180°C. This is second only to tungsten. The high melting point, coupled with its ability to maintain ductility even after recrystallization, offers many advantages. Rhenium also offers high electrical resistivity over a wide temperature range. The resistivity is higher than tungsten. This characteristic, plus having a low vapor pressure, make it a good choice for filaments. This is especially true when considering ductility and the fact that it is not affected by the oxidation/reduction cycle as is tungsten. Excellent data on rhenium can be found at http://www.rembar.com/tant.htm.

Since it maintains its ductility after recrystallization, it can easily be welded without fear of a brittle weld area. It also remains extremely ductile after welding.