Standard No.:	GB/T 223.78-2000
Chinese Name:	钢铁及合金化学分析方法 姜黄素直接光度法测定硼含量
English Name:	Methods for chemical analysis of iron,steel and alloy-Curcumin spectrophotometric method for the determination of boron content
Professional Classification:	H11 Steel and iron alloy analysis method
Professional Classification:	GB National Standard
ICS Classification:	77.080
Issued by:
Issued on:	2000-10-25
Implemented on:	2001-09-01
Status:	VALID
Language:	English
File Format:	PDF
Word Count:	7000 words
Price(USD):	210 (USD)
Delivery:	via email in 1-3 business day

1 Scope

This standard specifies the determination of boron content in steel by curcumin spectrophotometric method.
This method is applicable to the determination of 0.0005 % (m/m) ~0.012 % (m/m) boron content in steel and 0.0001% (m/m) ~0.0005% (m/m) boron content in non-alloy steel.

2 Normative References

The following documents contain provisions which, through reference in this text, constitute provisions of this standard. At time of publication, the editions indicated are valid. All standards are subject to revision, and parties concerned are encouraged to discuss the possibility of applying the latest edition of the following standards. Members of IEC and ISO support the current effective international standard register.
ISO 385-1: 1984 Laboratory Glassware -- Burettes -- Part 1: General Requirements
ISO 648: 1977 Laboratory Glassware -- One-Mark Pipettes
ISO 1042: 1983 Laboratory Glassware -- One-Mark Volumetric Flasks
ISO 3696: 1987 Water for Analytical Laboratory Use - Specification and Test Methods
ISO 5725-1: 1994 Accuracy (Trueness and Precision) of Measurement Methods and Results -- Part 1: General Principles and Definitions
ISO 5725-2: 1994 Accuracy (Trueness and Precision) of Measurement Methods and Results -- Part 2: Basic Method for the Determination of Repeatability and Reproducibility of a Standard Measurement Method
ISO 5725-3: 1994 Accuracy (Trueness and Precision) of Measurement Methods and Results -- Part 3: Intermediate Measures of the Precision of a Standard Measurement Method
ISO 14284: 1997 Steel and Iron—Sampling and Preparation of Samples for the Determination of Chemical Composition

3 Principle

The sample is dissolved in hydrochloric acid, nitric acid and will decompose to boron compounds (such as nitride) in the action of phosphoric acid and sulfuric acid at 290℃. In the acetic acid-acetate buffer solution, the boric acid and curcumin will form colored compound. The photometric measurement is carried out at 543nm wave length.