Iridium belongs to the transition element of Group VIII of the periodic table. Iridium is a rare precious metal with element symbol Ir, atomic number 77 and atomic weight 192.2. The content of iridium in the earth’s crust is one ten-millionth, and it is often dispersed together with platinum group elements in various ores of alluvial deposits. In this article, let’s take a look at the iridium uses & properties.
The application of iridium mostly uses its high melting point, high hardness, and corrosion resistance. Iridium metal, along with iridium-platinum alloy and osmium-iridium alloy, has a very low loss and can be used to manufacture porous spinnerets. Spinnerets are used to extrude plastic polymers into fibers, such as rayon. Osmium-iridium alloys can also be used for compass bearings and weight scales.
Iridium has strong corrosion resistance and high-temperature resistance, so it is very suitable as an alloy additive. Some long-term components in aircraft engines are made of iridium alloy, and the iridium-titanium alloy is also used as a material for underwater pipes. The addition of iridium increases the hardness of the platinum alloy. Pure platinum has a Vickers hardness of 56 HV, while platinum alloys containing 50 percent iridium can exceed 500 HV.
Iridium is also often used in instruments that must withstand high temperatures. Iridium alloy can resist arc erosion, so it is an ideal material for spark plug electrical contacts. Cativa catalytic method is the process of converting methanol into acetic acid. In this process, iridium compounds can be used as catalysts.
The radioisotope iridium-192 is an important energy source in γ radiography, which helps in the non-destructive testing of metals. In addition, brachytherapy uses the gamma rays released by Ir to treat cancer. This treatment method places the radiation source near or inside the cancer tissue and can be used to treat prostate cancer, cholangiocarcinoma, and cervical cancer.
Made in 1889, the International Prototype Metre is made of an alloy containing 90 percent platinum and 10 percent iridium and is kept by the international bureau of weights and measures near Paris.
Unmanned spacecraft such as Voyager, Viking, pioneer and Cassini-Huygens, Galileo and New Horizons have all used thermal motors containing radioactive isotopes of iridium. Since the thermal motor has to withstand high temperatures up to 2000 ° C, the container wrapped with plutonium-238 isotope is made of iridium which is both hard and high temperature resistant.
Iridium is also used in X-ray telescopes. The mirror of the Chandra X-ray Observatory has a 60-nm-thick iridium coating. After testing a variety of metals, the X-ray reflectivity of iridium proved superior to nickel, gold, and platinum.
Iridium is white like platinum, with a little yellow. Iridium is hard and brittle, and its melting point is very high, so it is difficult to cast. The manufacturing process therefore generally uses powder metallurgy.
Iridium is the only metal that maintains excellent mechanical properties in temperature above 1600 ° C. Its boiling point is extremely high, ranking 10th among all elements. The density of iridium ranks second among all elements, only slightly lower than osmium (about 0.12% lower).
Iridium is one of the most resistant metals. At high temperatures, it can withstand almost all acids, aqua regia, molten metals, and even silicates.
Thank you for reading your article, hoping it can let you have a better understanding of iridium uses & properties. If you want to know more about iridium and other refractory metals, you can visit Advanced Refractory Metals (ARM) for more information.
Headquartered in Lake Forest, California, ARM is a leading manufacturer & supplier of refractory metals throughout the world. We offer our customers high-quality refractory metal products like tungsten, molybdenum, tantalum, rhenium, titanium, zirconium, etc.
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