球墨铸铁是我国广大工人阶级在毛主席“独立自主,自力更生”的教导下发展起来的,经过无产阶级文化大革命有了更大的发展,球铁的应用日益广泛。为了更好的保证球墨铸铁的质量,及时发现生产中的问题,稀土镁中问合金化学成份的控制在球铁处理工艺中是十分必要的。因此,必须开展中间合金的化学分析。一般的分析方法,处理试样均采用酸溶法(即氢氟酸溶解),这样就要在铂器皿中处 The ductile iron was developed under the guidance of Chairman Mao ’s “independence and self-reliance ” by the working class in our country. After the great proletarian cultural revolution has been greatly developed, ductile iron has become more and more widely used. In order to better ensure the quality of ductile iron and find out the problems in production, the control of the chemical composition of rare earth magnesium alloy is very necessary in the ductile iron treatment process. Therefore, the chemical analysis of the master alloy must be carried out. The general method of analysis, the sample is treated with acid solution (ie hydrofluoric acid dissolved), so we should place in the platinum vessel