| Rhenium is one of the last naturally occurring elements to be discovered. (see background) It is right next to tungsten on the periodic table. Rhenium is known for its high melting point 3,180° C and its high density 21.04 g/cc- (5700 ° F and about 3/4 of a pound per cubic inch). One of the key reasons 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! 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 and other rather unique properties make it the material of choice for many critical applications. Most rhenium today is produced as a by-product of the copper mining industry. It is found in those copper ores contaminated with molybdenum. When they purify the copper the rhenium is extracted with the molybdenum in the form of sulfurous sludge. The high temperature roasting of the sludge to form molybdenum oxide releases the rhenium and it is collected and concentrated in special units. The next step is to make a medium purity ammonium salt containing rhenium called ammonium perrhenate (APR). This APR is sold around the world to various metal traders and catalyst manufacturers and is also used by Rhenium Alloys, Inc. We refine it to high purity at our in-house facility and produce a variety of powders, chemicals and fabricated materials.
Workable and weldable, rhenium simplifies the fabrication process
Although a highly dense element (21.04 g/cc at room temperature), rhenium's ductility is retained after complete recrystallization at high temperatures. Rhenium keeps it strength and will not become brittle from welding.
Rhenium can be welded using inert gas or electron beam methods when protected against oxidation. ECM (electrochemical machining), EDM (electrical discharge machining), and abrasive cutting/grinding methods achieve excellent results for rhenium and rhenium alloys. Rhenium offers high electrical resistivity across a wide temperature range. Its high temperature strength gives flexibility in design. Rhenium has the third highest modulus of elasticity of any metallic element.
____________________________________________________________________________________________________ "You have nothing without your health." Lou Guazzelli, whose time is of the essence. Prayers with you, Uncle Lou. 
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