The PGMs or Platinum Group Metals are referred to as the six transitional metals that are physically, chemically as well as anatomically similar. They are the densest metal elements ever known. Uniquely rare, they also occur in the same ore bodies. They are extremely durable and because of their higher value, they are often recycled which makes them more durable. On the periodic table as well, these noble metals are placed so close to one another and they are termed as transition metals. They are classified into sub groups:
- The iridium-group platinum group elements or IPGEs
- The palladium-group platinum group elements or PPGEs
The six PGMs are as follows:
- Iridium (Ir)
- Osmium (Os)
- Palladium (Pd)
- Platinum (Pt)
- Rhodium (Rh)
- Ruthenium (Ru)
The IPGE group entails osmium, ruthenium, and iridium. And the PPGEs entail rhodium, platinum and palladium.
Features of PGMs
- Platinum is deemed the best metal among this group and a major chunk of it is used in the jewelry department. It is dense, stable, and rare in nature and is also widely used in medical and electronic department as well.
- Palladium is considered a soft and silvery white metal which is famous for its catalytic features. It also has the highest melting point, but also the lowest melting point in all the PGMs. Both palladium as well as the platinum are used as PGM catalysts. In other words, they tend to speed up the chemical reactions without being chemically changed in the process. Visit this site, if you want to know more about PGM catalyst.
- Iridium is deemed the most common corrosion proof pure metal which can also be salt-, oxide-, and mineral acid-proof. However, it is impacted by sodium chloride and sodium cyanide as well. It also has a high melting point and is deformation proof. Hence, an excellent alloy strengthener.
- Rhodium as well as iridium are hard in nature and are tough to work with. Albeit, the chemical compounds of these metals are useful in alloy applications. Rhodium is considered as a catalyst material and bears high reflectance. It has a low electrical resistance as well as a low and stable contact resistance.
- Osmium and ruthenium have hard and brittle natures. They also have a poor resistance to oxidation but are deemed precious alloy additives and catalysts.