钢铁中微量钙的测定用络合滴定法误差大,不适用。以比色法最恰当。前川静弥用氟化物分离,二环己酮草酰双腙间接比色法测定钢中钙;田辺伊佐雄等用乙醚萃去铁,再于pH7.5～8.0分离锰及残余铁,用1-羟基-4-氯-2,2-二偶氮苯-1,8-二羟基萘-3,6-二磺酸钠(Plas-mocorinth B,CI 16680)作为显色剂;也有用汞阴极电解,再用铜试剂分离残余干扰元素,然后 Determination of trace calcium in steel with complex titration error, not applicable. Colorimetric method is the most appropriate. Maekawa static separation with fluoride, dicyclohexanone oxalic acid double hydrazone indirect colorimetric determination of calcium in steel; Tanaka Yi Zuo Xiong extracted with iron and other diethyl ether, and then at pH7.5 ~ 8.0 separation of manganese and iron, with 1- Plas-mocorinth B (CI 16680) was also used as a color former; mercury cathode electrolysis was also used , And then use the copper reagent separation of residual interference elements, then