稀贵金属,也叫铂族金属,系指元素周期表中第八族的铂Pt、钯Pd、铑Rh、铱Ir、锇Os和钌Ru。它们在地壳中的含量极低,铂和钯的含量约0.005-0.01 ppm,铑、铱、锇和钌的含量约为0.001 ppm。稀贵金属的物理力学性能优异、化学性质极为稳定,富有非凡的催化性能和对气体的吸附能力,难熔,铂、钯的可塑性、可煅性、可延性和可拉伸性均好。因之,这些金属及其合金或化合物广泛用于宇宙航行、核能、电子、石油、化学和精密仪器制造等传统和新兴工业 The rare metal, also called platinum group metal, refers to platinum Pt, palladium Pd, rhodium Rh, iridium Ir, osmium Os and ruthenium Ru of Group VIII of the periodic table. They are extremely low in the earth’s crust and contain about 0.005-0.01 ppm of platinum and palladium and about 0.001 ppm of rhodium, iridium, osmium and ruthenium. Precious metals have excellent physical and mechanical properties, extremely stable chemical properties, extraordinary catalytic performance and gas adsorption capability. Refractory, platinum, palladium plasticity, calcinability, ductility and stretchability are all good. As a result, these metals and their alloys or compounds are widely used in traditional and emerging industries such as space navigation, nuclear energy, electronics, petroleum, chemical and precision instrument manufacturing