Pt-iridium wire is a platinum-based binary alloy containing selenium. It is a continuous solid solution at high temperature. When slowly cooled to 975~700 ºC, solid phase decomposition occurs, but the phase equilibrium process proceeds very slowly. It can significantly improve the corrosion resistance of platinum due to its easy volatilization and oxidation. There are Ptlr10, Ptlr20, Ptlr25, Ptlr30 and other alloys, with high hardness and high melting point, high corrosion resistance and low contact resistance, the chemical corrosion rate is 58% of pure platinum, and the oxidation weight loss is 2.8mg/g. It is a classic electrical contact material. Used for high ignition contacts of aero-engines, electrical contacts of relays with high sensitivity and Wei motors; potentiometers and conductive ring brushes of precision sensors such as aircraft, missiles and gyroscopes

Widely used in chemical plants, filaments, spark plugs