Platinum metals include such metals as platinum, palladium , rhodium , iridium, ruthenium and osmium, which have white colour of different variations. Before World War II platinum was mainly used in the manufacture of jewellery (more than 50%), but the valuable properties of platinum made its use in jewellery irrational. Currently, about 90% of platinum is used in science and industry, the proportion of platinum jewellery is far less. This unique combination of such platinum properties as heat resistance, acid resistance and properties' constancy by calcination made platinum indispensable. Platinum is applied in manufacture of cups, crucibles, cans, vanes, spoons, spatulas, nozzles, filters, electrodes and etc. Platinum and its alloys are also used for the manufacture of surgical armaments. They are sterilized in alcohol burner flame without being oxidized, which is especially important when operating in field conditions. Platinum alloys are alloyed with such metals as palladium, silver, copper , zinc, nickel. Since these alloys do not have a flavour and are not subjected to oxidation with time, they are widely used in dentistry.
Iridium is mostly applied as an alloying element, as the metal improves the mechanical and physicochemical properties of other metals. It is usually used for improving the alloys' specific strength and hardness.
Palladium in turn is characterized by suitability for polishing, good processability, low melting temperature and relative cheapness. It is more often used in jewellery, as compared with other platinum metals. So palladium is used as a setting for precious stones. It is also popular as alloying element of white gold (an alloy of gold, refined with palladium additive) and is used as a material for watch cases.
Performance of platinum electrolyte-plasma treatment and polishing:
Recommended processing time for platinum polishing — 180 sec.
Grinding and deburring speed — 40 sec.
Average time to reduce the roughness value by 1 class — 90 sec.
The number of polishing cycles before changing the electrolyte — 30.