Standard No.:	GB/T 223.20-1994
Chinese Name:	钢铁及合金化学分析方法 电位滴定法测定钴量
English Name:	Methods for chemical analysis of iron steel and alloy.The Potentiometric titration method for the determination of cobalt content
Professional Classification:	H11 Steel and iron alloy analysis method
Professional Classification:	GB National Standard
ICS Classification:	77.080
Issued by:
Issued on:	1994-01-17
Implemented on:	1994-10-01
Status:	VALID
Language:	English
File Format:	PDF
Word Count:	2500 words
Price(USD):	75 (USD)
Delivery:	via email in 1-3 business day

1 Subject Content and Application Scope
This Standard specifies a method for the determination of the cobalt content using a potentiometric titration method.
This Standard is applicable to the determination of cobalt content in alloy steel, high temperature alloy and precious alloy. Determination range: above 3.00%.
2 Principle
Cobalt is oxidized using potassium ferricyanide in the ammoniacal medium in the presence of ammonium citrate and excessive potassium ferricyanide is subject to back titration with cobalt sulfate standard solution.
No more than 30 mg of chromium, 5mg of copper and 3mg of manganese in the titrated solution has no influence on its determination.