镁是国防上的重要战略物资。研究新球化剂钙合金代替镁球化剂,引起了人们的重视。加进铸铁中钙含量甚低,都在0.00x％。用化学法测定,迄今尚有困难或因几次富集而烦琐。目前国内有些单位采用了具有简便快速的原子吸收法测定易切屑钢中的微量钙。为了减少共存元素的化学干扰和提高测定的灵敏度,最好使用笑气 Magnesium is an important strategic material for national defense. Study of new nodular agent calcium alloy instead of magnesium nodulizer, has attracted people’s attention. Added to the low iron content of cast iron, all at 0.00x%. Measured by chemistry, so far there are difficulties or due to several enrichment and cumbersome. At present, some units have adopted a simple and rapid method of atomic absorption spectrometry for the determination of trace calcium in free-cutting steel. In order to reduce the chemical interference of co-existing elements and improve the sensitivity of the assay, it is best to use nitrous oxide gas