GB/T 11261-2006Steel and iron Determination of oxygen content The pulse heating inert gas fusion-infra-red absorption method (English PDF)

Foreword

This Revision of this Standard mainly modified the following contents.

--- Modified the standard name;

7 Preparation of Apparatus";

10 Test Report";

--- Added Appendix A;

--- Original 1, modified the name and contents of this Chapter;

--- Original 2, modified the normative references of this Chapter;

--- Original 3, modified the name of this Chapter;

--- Original 6, modified the name of this Chapter;

--- Original 7 is changed into 8, modified the contents of this Chapter;

--- Original 8 is changed into 9, modified the contents of this Chapter. This Standard replaced GB/T 11261-1989 Methods for Chemical Analysis of High Carbon Chromium Bearing Steel; the Pulse Heating Inert Gas Fusion; Infra-Red Absorption Method for the Determination of Oxygen Content. Appendix A of this Standard is informative. This Standard was proposed by China Iron and Steel Industry Association. This Standard shall be under the jurisdiction of National Technical Committee for Standardization of Steel. Drafting organizations of this Standard. Baosteel Group Shanghai No.5 Steel Co., Ltd.. Participating drafting organizations of this Standard. National Center for Quality Supervision & Testing of Iron and Steel, Wuhan Iron and Steel (Group) Corporation, Baosteel Group Shanghai Iron and Steel Research Institute, Baosteel Group Shanghai No.1 Steel Co., Ltd., Shandong Metallurgical Science Research Institute, Shanghai Research Institute of Materials, and Fushun Special Steel Co., Ltd.. Chief drafting staffs of this Standard. Wang Yujuan, Cui Qiuhong, Fan Yongfei, and Yu Xinxia. This Standard was first-time published in 1989. Steel and Iron - Determination of Oxygen Content - The Pulse Heating Inert Gas Fusion-Infrared Absorption Method

1 Scope

GB/T 11261-2006 is the Chinese national standard on steel and iron determination of oxygen content the pulse heating inert gas fusion-infra-red absorption method, in the field of metallurgy. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 2 March 2006 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 September 2006. Classification: ICS 77.080.01, CCS H11. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This Standard specifies using the pulse heating inert gas fusion-infrared absorption method to determine the oxygen content in the steel and iron. This Standard is applicable to the determination of oxygen content with mass fraction of 0.0005%~0.020% in the steel and iron.

2 Normative References

The provisions in following documents become the provisions of this Standard through reference in this Standard. For dated references, the subsequent amendments (excluding corrigendum) or revisions do not apply to this Standard, however, parties who reach an agreement based on this Standard are encouraged to study if the latest versions of these documents are applicable. For undated references, the latest edition of the referenced document applies.

GB/T 6379 (all Parts) Accuracy (Trueness and Precision) of Measurement Methods and Results

3 Principles

Put the pre-prepared test materials into the graphite crucible in the helium (or argon) airflow; use low-voltage AC to directly heat to about 2300°C to fuse; the oxygen in the test materials is precipitated in the form of carbon monoxide (or through heating 400°C rare earth copper oxide to change into carbon dioxide); introduce the infrared detector to determine.

4 Reagents and Materials

4.1 Helium (or argon) gas with purity 99.99% above.

6 Sampling and Sample Preparation

6.1 The specimen shall be machine-made a round bar with Phi (4~5) mm, length greater than 30mm, surface roughness Ra 3.2µm above. Polish the silicon carbide emery cloth and deerskin successively at the speed of about 800r/min till Ra is 1.6µm above; after polishing, cut off the end with thread cutter, cut off the required length; then clean with carbon tetrachloride (or ether) and acetone (4.4) successively in the ultrasonic cleaner for 3min~7min; dry with hot air, and place in the dryer for backup.

6.2 Specimen shall be prevent oxidation and contamination during the operating period, machine-making shall be performed at speed of 800r/min to add coolant; turning tool and thread cutter shall be cleaned by carbon tetrachloride (or ether) (4.3) in advance.

6.3 The bottom specimen through washing shall be taken by the tweezers rather than touch with hand. NOTE. When determining the high content of oxygen, other methods can also be used to remove the oxygen attached on the specimen surface.

7 Preparation of Apparatus

7.1 The apparatus shall be in the normal state before analysis.

7.2 Check with oxygen certified standard material (4.10) before analysis; the standard oxygen content of the used material shall be slightly greater than the oxygen content of analyzed specimen; the extreme deviation value among three calibration values is less than the repeatability value; otherwise re-calibrate.

8 Analytical Procedures

8.1 Test materials Weigh 0.5g~1.0g of specimen, accurate to 1mg.

8.2 Blank test The determination of blank value shall firstly return the blank value of original storage to zero; then perform the blank test according to the apparatus specified procedures and provisions of 8.3.2. If the determined oxygen content <=0.0030%, the blank value shall be less than 0.00005%.

10 Test Report

The test report shall contain the following contents.

a) All materials required by identifying the sample, laboratory, and test date;

b) The used standards and methods;

c) Test results and expressions;

d) Abnormal phenomena observed during the test period;