High Purity Rhenium Refined by Zone-Refining Process

Rhenium is classified as a refractory metal due to its extremely high melting point of 3180º C. Rhenium’s melting point is exceeded only by tungsten. And it is a very dense metal, having a density of 21.04 g/cc which is exceeded only by iridium, osmium and platinum. Unique among refractory metals, rhenium does not have a ductile-to-brittle transition temperature as it remains ductile from absolute zero up to its melting point of 3180º C. And thanks to its high re-crystallization temperature & high modulus of elasticity, parts produced from rhenium offer very good stability & rigidity and can withstand wide swings in temperature without being damaged.

Pure Rhenium is offered in three grades. For Rhenium metal, commercially minimum purity is 99.95% or 99.995% zone-refined, which is for applications that demand the higher purity. As for Rhenium powder, 99.999% is available.

What is “Zone Refining”?

Zone refining is a highly technological method for ultra-purification of metals. The principle of zone refining is that the impurities in an ingot of metal are more soluble in the melt state than they are in the corresponding solid state. In the zone refining process, the impurities are concentrated at one end of the ingot of metal so that the rest of the ingot is ultra-purified. It is an effective and easy method for ultra-purifying high-purity metals like Gallium, Germanium, Rhenium and others.  

Zone Refining Process

In the zone refining process, a circular mobile heating element is fixed at one end of the metal ingot to be purified. As the circular mobile heating element is moved slowly across the metal rod, the metallic impurities melt at the temporary position of the heating element. As the heating element moves forward, it increases the concentration of the impurities in the melt area. This is due to the fact that the metallic impurities are more soluble in their melt state than in their solid state. The melt containing the metallic impurities moves forward along with the heating element through the entire length of the metal ingot and the pure metal is left to solidify as the heating element moves forward along the ingot. The melting process is repeated many times in the same direction. Finally, the metallic impurities have accumulated at one end of the metal ingot. The end of the ingot containing the accumulated impurities is then cut off, leaving behind an ultra-pure metal ingot.

American GMG supplys high quality Rhenium products with purity up to 99.999% and its alloys as well as their related products as the following:

• Rhenium metal, bars, rods, plates, tubes, foils, wires, disks, powders, evaporation materials and sputtering targets, metallic powder and other customized Rhenium products and machined parts

• Ammonium Perrhenate (APR) (NH₄ReO₄), Rhenium trioxide (ReO₃), Rhenium Diboride (ReB2), Rhenium(VII) oxide (Re₂O₇), Rhenium (III) Chloride (ReCl₃), Rhenium (V) Chloride (ReCl₅) and other customized Rhenium chemicals.

• Rhenium alloys such as Tungsten-Rhenium, Molybdenum-Rhenium and its alloy products and machined parts or semi-finished and finished parts, custom sizes, and custom grades.

If you are in need of Rhenium (Re) metal and its related products, please contact us for details at sales@american-gmg.com.