GB/T 7737-2007Ferroniobium (English PDF)

Foreword

The degree of consistency between this Standard and ASTM A550-06 is non-

equivalent.

This Standard replaces GB/T 7737-1997 "Ferroniobium".

The revision of this Standard made modifications to the followings.

- adjusted some chemical compositions of GB/T 7737-1997;

- GB/T 7737-1997 has five designations and this Standard has seven;

- added the method for arbitration;

- added Annex A.

Annex 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 Metallurgical Industry

Information Standards Institute.

Main drafting organization of this Standard. Conghua Tantalum and Niobium

Smelter.

The drafting organizations of this Standard. CITIC Metal, Yingde Jiate New

Material Co., Ltd., Metallurgical Industry Information Standards Institute.

Main drafters of this Standard. Liang Yongtai, Wang Weizhe, Wu Lijue, Zhang

Ruixiang, Zeng Guozhong, Li Huichao, Zhong Yuelian, Huang Shuang, Lin

Shaoping.

Versions of standard substituted by this Standard are.

- GB/T 7737-1987, GB/T 7737-1997.

Ferroniobium

1 Scope

This Standard specifies technical requirements, test methods, inspection rules,

packaging, storage, marks and quality certificate of ferroniobium.

This Standard is applicable to ferroniobium that is made from niobium pentoxide

and niobium concentrate and is used for steelmaking or casting as an additive,

for electrode as alloying agent, magnetic material.

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 3650, The general rules for inspection packing storing transportation

marking and certification of ferroalloy

GB/T 3654.1, Methods for chemical analysis of ferroniobium. The paper

chromatographic gravimetric method for the determination of niobium and

tantalum content

GB/T 3654.3, Ferroniobium - Determination of silicon content - Gravimetric

method

GB/T 3654.4, Methods for chemical analysis of ferroniobium. The

combustion gravimetric method for the determination of carbon content

GB/ T 3654.5, Methods for chemical analysis of ferroniobium. The

molybdenum blue photometric method for the determination of the

phosphorus content

GB/T 3654.6, Ferroniobium - Determination of sulfur content - Combustion-

iodate titrimetric method, methylene blue photometric method and infrared

absorption method

GB/T 3654.7, Methods for chemical analysis of ferroniobium - The methylene

blue photometric method for the determination of sulfur content

3 Technical requirements

4 Test methods

5 Inspection rules

6 Packaging, storage, marks and quality certificate

The packaging, storage, marks and quality certificate of ferroniobium shall

comply with the provisions of GB/T 3650.

Annex A

(informative)

Determination of arsenic, antimony, lead, tin, bismuth and manganese in

ferroniobium - Inductively coupled plasma emission spectroscopy

A.1 Scope

This annex specifies the method that uses inductively coupled plasma emission

spectroscopy to determine arsenic, antimony, lead, tin, bismuth, manganese in

ferroniobium.

This Annex is applicable to the determination of arsenic, antimony, lead, tin,

bismuth, manganese in ferroniobium. Determination range. the mass fraction

of arsenic, antimony, lead, tin, bismuth is 0.001%~1.0%; the mass fraction of

manganese is from 0.001%~2.0%.

A.2 Method summary

Use hydrofluoric acid and nitric acid to decompose the sample and dilute to a

certain volume. Through matrix matching, eliminate spectral interference.

Introduce atomized solution into the inductively coupled plasma emission

spectrometer. Determine the luminous intensity values of arsenic, antimony,

lead, tin, bismuth, manganese and other elemental analysis lines. Determine

the mass fraction of the corresponding element by the working curve method.

A.3 Reagents and materials

A.3.8 Antimony standard solution 1000µg/mL. Weigh 1.0000g of high-purity

antimony. Place in a 250mL beaker. Add 90mL of hydrochloric acid (A.3.4),

30mL of nitric acid (A.3.2). Heat to dissolve. Move into a 1000mL volumetric

flask. Use pure water to dilute to the scale. Mix well.

1mL of this solution contains 1000µg of antimony.

A.3.9 Lead standard solution 1000µg/mL. Weigh 1.0000g of high-purity lead.

Place in a 250mL beaker. Add 150mL of nitric acid (A.3.3). Heat to dissolve.

Move into a 1000mL volumetric flask. Use pure water to dilute to the scale. Mix

well.

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