In the forging process, the induction furnace argon is used for shielding smelting, the ingot must be heated and then processed for cold processing, and the fine wire of 0.008mmP-tIr25 alloy is drawn. It is difficult to smelt and process 60% iridium alloy by electric arc furnace.
(1) platinum iridium alloy has high melting point, high density, high hardness, high strength and high elasticity. These properties are enhanced with the increase of iridium concentration.
(2) the alloy containing more than 10% iridium has an aging hardening effect and increases with the increase of iridium concentration, but the precipitation rate is low.
(3) the resistivity of platinum-iridium alloy increases with the increase of Ir concentration, while the resistivity temperature coefficient decreases. Platinum-iridium alloy has low contact resistance, but it is easy to be polluted by organic atmosphere. Platinum-iridium alloy presents positive thermoelectric potential to platinum-and increases with the increase of iridium concentration.
(4) the addition of iridium into platinum significantly improves the chemical resistance of platinum, and the alloy containing more than 30% iridium is actually free from the corrosion of boiling king water.
(5) as the iridium concentration and heating temperature rise, the volatile weight loss of platinum-iridium alloy increases.
(6) platinum-iridium alloy has high deformation resistance and hardening rate, and its processing performance decreases with the increase of iridium content. The inner segregation and dendrites of the alloy are well developed.
