近年来的研究表明,稀土元素是铜合金中良好的细化剂,不仅能除去金属中的气体和有害杂质,还能控制浇注时的宏观偏析.用稀土铜合金铸造的推进器,强度高,塑性好,性能优良,服役寿命长.合金中稀土加入量一般为0.00x～x%之间.三溴偶氮胂是不对称变色酸双偶氮类显色剂(简称TBA),在较强的酸性溶液中与稀土元素形成十分稳定的蓝紫色络合物,其摩尔吸光系数ε=1.3×10~5.最大吸收波长为630～640nm.在25ml In recent years, studies have shown that the rare earth element is a good refiner in copper alloy, not only to remove the gas and harmful impurities in the metal, but also to control the macroscopic segregation during casting.Radium casting with rare earth alloy, high strength, Plasticity, good performance, long service life. The amount of rare earth added to the alloy is generally between 0.00x ~ x% .Tribromine arsenazo asymmetric chromotropic acid disazo color reagent (referred to as TBA), in the stronger Acid solution with rare earth elements to form a very stable blue-purple complex, the molar extinction coefficient ε = 1.3 × 10 ~ 5. The maximum absorption wavelength of 630 ~ 640nm in 25ml