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前言高速钢中锰、铬和钒三元素的测定,一般都采用氧化还原容量滴定法,分别称取样品单独进行测定:锰——过硫酸盐银盐法;铬——过硫酸盐银盐-高锰酸钾逆滴定法;钒——高锰酸钾容量法。由于高速钢中含锰量较少(<0.4%),含铬量较高(3.8～4.4%),在锰氧化之前生成的铬酸的黄色,防碍锰的滴定,使滴定终点难以判别。因此,一般文献都提到:对于含铬2%以上的钢,必须预先用氧化锌分离铬或用碳酸氢钠分离铬,其分离手续烦琐,很费时间,不能满足生产要求。上海材料研究所采用过硫酸盐光电比色法测定不锈钢中的锰和铬钢中的锰,此法
Preface High-speed steel in the determination of manganese, chromium and vanadium three elements, are generally used by the redox volumetric titration, were weighed samples were measured separately: manganese - persulfate silver salt; chromium - persulfate silver salt - Potassium permanganate reverse titration; Vanadium - potassium permanganate capacity method. High-speed steel contains less manganese (<0.4%), high chromium content (3.8 ~ 4.4%), chromic acid generated before oxidation of manganese yellow, hinder the titration of manganese, the end point of titration difficult to distinguish. Therefore, the general literature mentions that for steels containing more than 2% chromium, chromium must be separated from zinc oxide or sodium bicarbonate in advance. The separation procedure is cumbersome and time consuming to meet the production requirements. Shanghai Institute of Materials used persulfate photoelectric colorimetric determination of manganese and chromium in stainless steel manganese, this method