ICS 77.140.

20

H 40

National standard of the People’s Republic of China

GB/T 699-1999

Quality Carbon Structural Steels

Issued on November 1, 1998 Implemented on August 1, 2000

Issued by the State Bureau of Quality Technical Supervision Bureau

GB-T 699-1999 Quality Carbon Structural Steels

Foreword

This standard is a revision on GB/T 699-1998 "Specifications for Quality Carbon Structural Steels".
The current revision of this standard has made modifications in respect of the following items:
— The name of standard is changed to "Quality carbon structural steels";
— The applicable scope is extended to such extent that quality carbon structural steels with diameter or
thickness greater than 250mm may be supplied;
— The chapter of "Order Information" is added;
— Th size, dimensions and allowance shall be in accordance with the stipulations in standard GB/T
702-1986 or GB/T 908-1987;
— Marking symbols of steel products and unified numerical representation for various designations are
added;
— The range of carbon content for designations below 40 (with exception of 08F) is narrowed by 0.01%;
— The phosphorus and sulfur contents and macroscopic structure of steels are classified into three grades
based on the metallurgical quality;
— For steels delivered in the hot-rolled or hot forged state, the mechanical properties may be exempted
from inspection if the supplier can guarantee the conformance;
— In note 2 of Table 3, the quench cooling medium for designation 75, 80 and 85 steels is changed from
"water cooling" to "oil cooling";
— The "fracture" test is cancelled;
— The acceptable grading of non-metallic inclusions is cancelled.
This standard shall replace GB/T 699-1988 "Specifications for Quality Carbon Structural Steels" since its
implementation.
This standard is proposed by the State Bureau of Metallurgical Industry.
This standard shall be under the jurisdiction of the National Technical Committee of Steel Standardization.
This standard is prepared mainly by the Information Standard Institute of the Ministry of Metallurgical
Industry, Chongqing Special Steel Co., Shanghai Pugang Group Corporation, Daye Special Steel Co., Ltd. and
Handan Iron and Steel Corporation.
Main draftsmen of this standard are: Luan Yan, Tang Yifan, Tang Zhibai, Chen Changxi, Sun Ping, Teng
Changling, Zhao Gaunxin
This standard was initially issued in January 1965 and revised for the first time in February 1988.

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 GB-T 699-1999 Quality Carbon Structural Steels

NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA

GB/T 699-1999
Replace GB/T 5785-1988

Quality Carbon Structural Steels

1. Scope

This standard defines the size, dimensions, weight and allowance, technical requirements, test methods,
inspection rules, packaging, marking and quality certificates of hot rolled or forged quality carbon structural
steels.
This standard is applicable to quality carbon structural steel bars with diameter or thickness not greater
than 250mm. Those with diameter or thickness greater than 250mm may also be supplied as agreed between
the buyer and the supplier.
The designations and chemical composition as specified in this standard is also applicable to steel ingots,
steel billets and their manufactur.

2. Normative Reference

Provisions from the following standards shall form part of this standard by being cited herein. At the time
of publication of this standard, the revisions of these standards as shown are valid. All standards shall be
subject to amendment and revision, and all users of this standard should probe into the possibility of applying
the updated revisions of the following standards.
GB/T 222-1984 Method for sampling of specimens for chemical analysis of steels and allowance for
chemical composition of finished products
GB/T 224-1987 Method for decarburized layer depth test of steels
GB/T 226-1991 Method for acid attack test of macroscopic structure and imperfection of steels
GB/T 228-1997 Method for tensile test of metals
GB/T 229-1994 Metallic Material - Charpy notch impact test
GB/T 231-1984 Method for Brinnel hardness test of metals
GB/T 233-1982 Method for upsetting test of metals
GB/T 702-1986 Size, dimensions, weight and allowance of hot rolled round and square steels
GB/T 908-1987 Size, dimensions, weight and allowance of forged round and square steels
GB/T 1979-1980 Grading diagrams for evaluation of macroscopic structural imperfections of structural
steels
GB/T 2101-1989 General stipulations on acceptance, packaging, markings and quality certificates of
profile steels
GB/T 2975-1998 Steel and steel products - Location and preparation of test specimens for mechanical
testing
GB/T 4336-1984 Method for photoelectric emission spectroscopic analysis of carbon steel, medium and
low alloy steel
GB/T 6397-1986 Specimens for tensile test of metals
GB/T 7736-1987 Ultrasonic inspecting method for macro-structure and imperfection of steel
GB/T 10561-1989 Steel - Determination of content of non-metallic inclusion -Micrographic method using
standard diagrams

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 GB-T 699-1999 Quality Carbon Structural Steels

GB/T 17616-1998 Unified numbering system for designations of iron, steel and alloy
GB/T 13299-1991 Steel - Determination of microstructure
GB/T 15711-1995 Steel products - Methods for acid etch test of tower sample
GB/T 17505-1998 Steel and steel products - General technical delivery requirements
YB/T 5148-1993 Method for the test of mean grain fineness of metals
See Annex A (Annex to the Standard) for normative references for chemical analysis methods of various
elements in steel.

3. Order Information

Contracts concluded or purchase orders placed in compliance with this standard should contain the
following information：
a）Standard code number；
b）Description of product；
c）Designations or unified numerical code；
d）Weight (quantity) of delivery；
e）Class of accuracy for specification and size；
f）Processing method used；
g）State of delivery；
h）Impact test (where required, as per 6.4.1)；
i）Upsetting test (where required, as per 6.5)；
j）Non-metallic inclusion (where required, as per 6.7)；
k）Decarburized layer (where required, as per 6.8)；
l）Special requirements (where required, as per 6.10)；

4 Classification and Code

4.1 Steel material is classified according to its metallurgical quality as follows:

Quality Steel
Premium-grade Quality Steel A
Special-grade Quality Steel E
4.2 Steel material is classified into two categories according to the processing method used:
a) Steel for pressed work UP
Steel for hot pressed work UHP
Steel for upsetting work UF
Steel for cold drawn billet UCD
b) Steel for cutting work UC

5 Size, Dimensions, Weight and Allowance

5.1 The size, dimensions and allowance of hot rolled round steels and square steels should comply with
relevant stipulations in GB/T 702. Specific requirements should be clearly stated in the contract.
5.2 The size, dimensions and allowance of forged round and square steels should comply with relevant
stipulations in GB/T 908. Specific requirements should be clearly stated in the contract.
5.3 The size, dimensions and allowance of steels with other cross-sections should comply with relevant
stipulations in corresponding standards.

6 Technical Requirements

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 GB-T 699-1999 Quality Carbon Structural Steels

6.1 Designation, Code and Chemical Composition

6.1.1 Designations, unified numerical code and chemical composition (smelting analysis) of steels should
comply with Table 1.
6.1.1.1 Sulfur and phosphorus contents of steels should comply with Table 2.
6.1.1.2 The allowable copper content of steels smelted with steel scrap should not be higher than 0.30%.
6.1.1.3 The copper content of steels for hot pressed work should not be higher than 0.20%.
6.1.1.4 The manganese content of 35~38 steels for lead-bath quenched steel wires should be 0.30%~0.60%;
the chromium content should not be higher than 0.10%, the nickel content should not be higher than 0.15%,
the copper content should not be higher than 0.20%; the sulfur and phosphorus contents should comply with
the requirements of steel wire standards.
6.1.1.5 For aluminum deoxidization smelted killed steel for 08 steels, the lower limit of manganese content is
0.25%, the silicon content should not be higher than 0.03% and the aluminum content should be 0.02%~0.07%.
In this case the designation of the steel is 08Al.

Table 1
Chemical composition,%
No. Unified Designation
C Si Mn Cr Ni Cu
numerical code
Not higher than
1 U20080 08F 0.05~0.11 ≤0.03 0.25~0.50 0.10 0.30 0.25
2 U20100 10F 0.07~0.13 ≤0.07 0.25~0.50 0.15 0.30 0.25
3 U20150 15F 0.12~0.18 ≤0.07 0.25~0.50 0.25 0.30 0.25
4 U20082 08 0.05~0.11 0.17~0.37 0.35~0.65 0.10 0.30 0.25
5 U20102 10 0.07~0.13 0.17~0.37 0.35~0.65 0.15 0.30 0.25
6 U20152 15 0.12~0.18 0.17~0.37 0.35~0.65 0.25 0.30 0.25
7 U20202 20 0.17~0.23 0.17~0.37 0.35~0.65 0.25 0.30 0.25
8 U20252 25 0.22~0.29 0.17~0.37 0.50~0.80 0.25 0.30 0.25
9 U20302 30 0.27~0.34 0.17~0.37 0.50~0.80 0.25 0.30 0.25
10 U20352 35 0.32~0.39 0.17~0.37 0.50~0.80 0.25 0.30 0.25
11 U20402 40 0.37~0.44 0.17~0.37 0.50~0.80 0.25 0.30 0.25
12 U20452 45 0.42~0.50 0.17~0.37 0.50~0.80 0.25 0.30 0.25
13 U20502 50 0.47~0.55 0.17~0.37 0.50~0.80 0.25 0.30 0.25
14 U20552 55 0.52~0.60 0.17~0.37 0.50~0.80 0.25 0.30 0.25
15 U20602 60 0.57~0.65 0.17~0.37 0.50~0.80 0.25 0.30 0.25
16 U20652 65 0.62~0.70 0.17~0.37 0.50~0.80 0.25 0.30 0.25
17 U20702 70 0.67~0.75 0.17~0.37 0.50~0.80 0.25 0.30 0.25
18 U20752 75 0.72~0.80 0.17~0.37 0.50~0.80 0.25 0.30 0.25
19 U20802 80 0.77~0.85 0.17~0.37 0.50~0.80 0.25 0.30 0.25
20 U20852 85 0.82~0.90 0.17~0.37 0.50~0.80 0.25 0.30 0.25
21 U21152 15Mn 0.12~0.18 0.17~0.37 0.70~1.00 0.25 0.30 0.25
22 U21202 20Mn 0.17~0.23 0.17~0.37 0.70~1.00 0.25 0.30 0.25
23 U21252 25Mn 0.22~0.29 0.17~0.37 0.70~1.00 0.25 0.30 0.25
24 U21302 30Mn 0.27~0.34 0.17~0.37 0.70~1.00 0.25 0.30 0.25
25 U21352 35Mn 0.32~0.39 0.17~0.37 0.70~1.00 0.25 0.30 0.25
26 U21402 40Mn 0.37~0.44 0.17~0.37 0.70~1.00 0.25 0.30 0.25
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 GB-T 699-1999 Quality Carbon Structural Steels

27 U21452 45Mn 0.42~0.50 0.17~0.37 0.70~1.00 0.25 0.30 0.25

28 U21502 50Mn 0.48~0.56 0.17~0.37 0.70~1.00 0.25 0.30 0.25
29 U21602 60Mn 0.57~0.65 0.17~0.37 0.70~1.00 0.25 0.30 0.25
30 U21652 65Mn 0.62~0.70 0.17~0.37 0.90~1.20 0.25 0.30 0.25
31 U21702 70Mn 0.67~0.75 0.17~0.37 0.90~1.20 0.25 0.30 0.25
Note: Those listed in Table 1 are quality steels. In case of premium-grade quality steel, letter "A" shall be added to the end of the
designation number (the last digit of the unified numerical code to be changed to "3"); in case of special-grade quality steel, letter
"E" shall be added to the end of the designation number (the last digit of the unified numerical code to be changed to "6"); for
rimming steel, the end of the designation number is "F" (the last digit of the unified numerical code being "0"); for semi-killed
steel, the end of the designation number is "b" (the last digit of the unified numerical code being "1").
6.1.1.6 The silicon content of rimming steel for cold punch pressing should not be higher than 0.03%.
6.1.1.7 The nitrogen content of steels smelted in oxygen-blown converters should not be higher than 0.008%.
If the supplier can guarantee the conformance, the analysis may be omitted.
6.1.1.8 As agreed between the buyer and the supplier, for 08~25 steels, semi-killed steels with
silicon content not higher than 0.17% may be supplied, with grade numbers of 08b~25b.
6.1.2 The allowance for chemical composition of steel material (or billets) should comply with the stipulation
in Table 2 of GB/T 222-1984.

Table 2
P S
Group Not higher than, %
Quality 0.035 0.035
Premium-grade 0.030 0.030
Special-grade 0.025 0.020

6.2 Smelting Method

Unless otherwise specified in the contract, the smelting method shall be chosen by the manufacturer of its
own accord.

6.3 State of Delivery

Steel material is normally delivered in the hot rolled or hot forged state. It may also be delivered in the
heat treated (annealed, normalized or high temperature tempered) if the buyer so requests and if so stated in the
contract.

6.4 Mechanical Properties

6.4.1 The longitudinal mechanical properties of steel material obtained by testing the specimen made with
heat-treated (normalized) work blank (excluding impact absorbed work) should comply with the stipulation in
Table 3. For steel material delivered in the hot rolled or hot forged state, if the supplier can guarantee the
conformance, the tests may be omitted.
As required by the buyer, the impact absorbed work of 25~50 and 25Mn~50Mn steels obtained by testing
the specimen made with heat treated (quenched + tempered) work blank should comply with the stipulation in
Table 3.
Round steels with diameter smaller than 16mm and square or flat steels with thickness not greater than
12mm shall not be subject to the impact test.
6.4.2 The mechanical properties shown in Table 3 are only applicable to steel material with cross-section size

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 GB-T 699-1999 Quality Carbon Structural Steels

not greater than 80mm. For that with cross-section greater than 80mm, the after-breaking elongation and
percentage reduction of section are allowed to be lower than those specified in Table 3 by 2% (absolute) and
5% (absolute) respectively.
Where steel material with size larger than 80mm to 120mm is re-forged to test piece sized between
70mm and 80mm, the result of the sampling test should comply with the stipulation in Table3.
Where steel material with size larger than 120mm to 250mm is re-forged to test piece sized between
90mm and 100mm, the result of the sampling test should comply with the stipulation in Table 3.
6.4.3 The hardness of steel material for cutting work or for cold drawn material in the delivery state should
comply with the stipulation in Table 3. For the hardness of non-annealed steel, if the supplier can guarantee the
conformance, the test may be omitted. The hardness indexes after high temperature tempering and
normalization shall be determined by agreement between the supplier and the buyer.

Table 3
Proposed heat Mechanical Properties Hardness of steel
treatment, ℃ material
Designation

No. Specimen σb σs δ5 % ψ% AKU2 J in delivery state

blank size MPa MPa HBS10/3 000
Normalization

Quenching

Tempering

mm
Not less than Non-heat Annealed
treated steel
steel
1 08F 25 930 295 175 35 60 131
2 10F 25 930 315 185 33 55 137
3 15F 25 920 355 205 29 55 143
4 08 25 930 325 195 33 60 131
5 10 25 930 335 205 31 55 137
6 15 25 920 375 225 27 55 143
7 20 25 910 410 245 25 55 156
8 25 25 900 870 600 450 275 23 50 71 170
9 30 25 880 860 600 490 295 21 50 63 179
10 35 25 870 850 600 530 315 20 45 55 197
11 40 25 860 840 600 570 335 19 45 47 217 187
12 45 25 850 840 600 600 355 16 40 39 229 197
13 50 25 830 830 600 630 375 14 40 31 241 207
14 55 25 820 820 600 645 380 13 35 255 217
15 60 25 810 675 400 12 35 255 229
16 65 25 810 695 410 10 30 255 229
17 70 25 790 715 420 9 30 269 229
18 75 specimen 820 480 1 080 880 7 30 285 241
19 80 specimen 820 480 1 080 930 6 30 285 241
20 85 specimen 820 480 1 130 980 6 30 302 255
21 15Mn 25 920 410 245 26 55 163
22 20Mn 25 910 450 275 24 50 197
23 25Mn 25 900 870 600 490 295 22 50 71 207
24 30Mn 25 880 860 600 540 315 20 45 63 217 187

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 GB-T 699-1999 Quality Carbon Structural Steels

25 35Mn 25 870 850 600 560 335 18 45 55 229 197

26 40Mn 25 860 840 600 590 355 17 45 47 229 207
27 45Mn 25 850 840 600 620 375 15 40 39 241 217
28 50Mn 25 830 830 600 645 390 13 40 31 255 217
29 60Mn 25 810 695 410 11 35 269 229
30 65Mn 25 830 735 430 9 30 285 229
31 70Mn 25 790 785 450 8 30 285 229
Notes:
1. For steel material with diameter or thickness less than 25mm, heat treatment is conducted on the specimen blank with
the same cross-section size as that of finished products.
2. The proposed temperature holding time for normalization as listed in the table is not less than 30 minutes with air
cooling; that for quenching is not less than 30 minutes with oil cooling for 75, 80 and 85 steels and water cooling for
other steels; that for tempering is not less than 1 hour.

6.5 Upsetting

6.5.1 Steels for upsetting work shall be subject to upsetting test and either hot upsetting or cold upsetting
should be clearly stated in the contract. The height of specimen after hot upsetting shall be as much as 1/3 of
that of the original specimen; the height of specimen after cold upsetting shall be as much as 1/2 of that of the
original specimen. No fissure or fracture shall exist on the specimen after the upsetting.
6.5.2 For steel material with size larger than 80mm that requires hot upsetting, or that with size larger than
30mm that requires cold upsetting, if the supplier can guarantee the conformance, the test may be omitted.

6.6 Macroscopic Structure

6.6.1 There should be no shrinkage cavity, blister, crack, inclusion, skull patch or fish eye visible to the naked
eyes on the cross-sectional pickled macroscopic structure specimen of killed steel material. Such imperfections
as subsurface inclusion not exceeding the allowable depth for surface imperfection are allowed on the steel
material for cutting work.
6.6.2 Pickled macroscopic structure should comply with the stipulation in Table 4.

Table 4
Quality grade General poriness Ingot mold aliqution
Level (not greater than)
Quality steel 3.0 3.0 3.0
Premium-grade quality steel 2.5 2.5 2.5
Special-grade quality steel 2.0 2.0 2.0

6.6.3 If the supplier can guarantee the conformance of macroscopic test, it is allowable to
substitute ultrasonic test or other nondestructive tests specified in standard GB/T 7736 for the
macroscopic test.

6.7 Non-metallic Inclusion

As required by the buyer, non-metallic inclusions may be tested with the acceptable levels to be defined by
agreement between the buyer and the supplier.

6.8 Decarburized Layer

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 GB-T 699-1999 Quality Carbon Structural Steels

When testing the decarburized layer of steels with nominal carbon content higher than 0.30%, as required
by the buyer, the total depth of decarburized layer on each side (ferrite + transition layer) should comply with
the stipulation in Table 5. The buyer should indicate the group in the contract .

Table 5
mm
Group Allowable total depth of decarburized layer (not higher than)
Group I 1.0%D
Group II 1.5%D
Note: D is the nominal diameter or thickness of steel material

6.9 Surface Quality

6.9.1 There should be no crack, rolling skin, folding or inclusion visible to the naked eyes on the surface of
steel material for pressed work. Any of the above imperfections should be removed to such extent that the
removed depth as calculated from the surface of steel material is in compliance with the stipulation in Table 6.
The width for removal should not be less than 5 times the depth. For steel material with diameter or side length
larger than 140mm, no more than 2 places with maximum removal depth are allowed on the same cross section.
It is allowable to have very few fine scratches, impression marks and pork marks with size not exceeding half
of the size allowance as calculated from the actual size and fine crackles with depth within 0.2mm in existence.
6.9.2 Local imperfections with depth not exceeding the stipulation in Table 7 as calculated from the nominal
size of steel material are allowable on the surface of steel material for cutting work.

Table 6
mm
Nominal size of steel material Allowable depth of imperfection removal
(diameter or depth)
< 80 1/2 of nominal size allowance of steel material
80~140 Nominal size allowance of steel material
>140 ~ 200 5% of nominal size of steel material
> 200 6% of nominal size of steel material

Table 7
mm
Nominal size of steel material Allowable depth of local imperfection
(diameter or thickness) (not greater than)
< 100 Negative allowance of nominal size of steel material
≥ 100 Allowance of nominal size of steel material

6.10 Special Requirements

As required by the buyer and so agreed between the buyer and the supplier, steel material meeting the
following special requirements may be supplied:
a) To narrow or modify the range of chemical composition specified in Table 1;
b) Steel bars with diameter or thickness larger than 250mm;
c) To test the grain fineness of steel;
d) To test the microstructure of steel;
e) To test the hair line seams with telescoping (tower) specimen;
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 GB-T 699-1999 Quality Carbon Structural Steels

f) To make the mechanical properties indexes stricter;

g) To make V-notched impact test (the indexes to be agreed between the buyer and the supplier);
h) Other.

7 Test Methods
Test methods for each and every batch of steel material should comply with the stipulation in Table 8.

Table 8
No. Test item Quantity of Location for sampling Test method
samples
1 Chemical 1 GB/T 222 GB/T 223
composition GB/T 4336
2 Tensile test 2 Different pieces of steel material GB/T 228
GB/T 2975
GB/T 6397
3 Hardness test 3 Different pieces of steel material GB/T 231
4 Impact test 2 Different pieces of steel material GB/T 229
5 Upsetting test 2 Different pieces of steel material GB/T 233
6 Macroscopic 2 Different pieces of steel billet or steel GB/T 226
structure material equivalent to the end of steel GB/T 1979
ingot
7 Telescoping 2 Different pieces of steel material GB/T 15711
(tower) hair line
seams
8 Decarburization 2 Different pieces of steel material GB/T 224
(metallo-graphic)
9 Grain fineness 1 Any piece of steel material YB/T 5148
10 Non-metallic 2 Different pieces of steel material GB/T 10561
inclusion
11 Microstructure 2 Different pieces of steel material GB/T 13299
12 Ultrasonic test 2 On the whole of steel material GB/T 7736
13 Size, Piece by On the whole of steel material Caliper,
dimensions piece micrometer
14 Visual aspects Piece by On the whole of steel material Visual inspection
piece

8 Test Rules

8.1 Inspection and Acceptance

8.1.1 The quality of steel material shall be inspected and accepted by the quality technical supervision
department of the supplier.
8.1.2 The supplier must ensure that the steel material delivered complies with the stipulations of this standard
or of the contract. The buyer is entitled to make inspection or acceptance to any of the test items defined in this
standard or the contract if necessary.

8.2 Batch Forming Rules

Steel material should be inspected and accepted batchwise. Each batch consists of steel material with the
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 GB-T 699-1999 Quality Carbon Structural Steels

same heat (furnace) number, the same working method, the same size, the same delivery state (or the same
heat treatment system/furnace lot) and the same surface state.

8.3 Quantity and Location for Sampling

The quantity and location for sampling of steel material should comply with the stipulation in Table 8.

8.4 Re-inspection and Judging Rules

8.4.1 The re-inspection and judging rules shall be in compliance with relevant stipulations in 8.3.4.3 of
standard GB/T 17505-1998.
8.4.2 If the supplier can guarantee the conformance of the steel material, it is allowable to substitute billet for
material or large pieces for small ones with respect to the test results of macroscopic test, mechanical
properties and non-metallic inclusion for the steel material or ingots with the same heat (furnace) number.

9 Packaging, Marking and Quality Certificate

Packaging, marking and quality certificates of the steel material should comply with the stipulations of
GB/T 2101.

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Annex A Annex to the Standard

Normative References - Methods for Chemical Analysis

GB/T 223.3 – 1988 Methods for chemical analysis of iron, steel and alloy
― The diantipyryl-methane phosphomolybdic acid gravimetric method for the
determination of phosphorus content
GB/T 223.5 – 1997 Methods for chemical analysis of iron, steel and alloy
― The reduced molybdosilicate spectrophotometric method for the
determination of acid-soluble silicon content
GB/T 223.10 - 1991 Methods for chemical analysis of iron, steel and alloy
― The determination of aluminum content by chrome azurol S
photometric method after separation with cupferron
GB/T 223.11 - 1991 Methods for chemical analysis of iron, steel and alloy
― The determination of chromium content by persulfate oxdation
volumetric method
GB/T 223.12 – 1991 Methods for chemical analysis of iron, steel and alloy
― The determination of chromium content by diphenyl carbazide
photometric method after separation with sodium carbonate
GB/T 223.18 - 1994 Methods for chemical analysis of iron, steel and alloy
― The sodium thiosulfate separation iodimetric method for the
determination of copper content
GB/T 223.19 - 1989 Methods for chemical analysis of iron, steel and alloy
― The determination of copper content by neocuprone-photometric
method
GB/T 223.23 - 1994 Methods for chemical analysis of iron, steel and alloy
― The dimethylglyoxime spectrophotometric method for the
determination of nickel content
GB/T 223.24 - 1994 Methods for chemical analysis of iron, steel and alloy
― The extraction separation - The dimethylglyoxime spectrophoto
method for the determination of nickel content
GB/T 223.36 - 1994 Methods for chemical analysis of iron, steel and alloy
― The neutral titration method for the determination of nitrogen
content after distillation separation
GB/T 223.37 - 1989 Methods for chemical analysis of iron, steel and alloy
― The indigo photometric method for the determination of nitrogen
content after distillation separation
GB/T 223.53 - 1987 Methods for chemical analysis of iron, steel and alloy
― The determination of copper content by flame atomic absorption
spectrophotometry
GB/T 223.54 - 1987 Methods for chemical analysis of iron, steel and alloy
― The determination of nickel content by flame atomic absorption
spectrophotometry
GB/T 223.58 – 1987 Methods for chemical analysis of iron, steel and alloy
― The determination of manganese content by sodium arsenite –
sodium nitrite titration method

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GB/T 223.59 - 1987 Methods for chemical analysis of iron, steel and alloy
― The determination of phospgorus content by
antimonium-Phosphorus-Molybdium-blue photometric method
GB/T 223.60 - 1997 Methods for chemical analysis of iron, steel and alloy
― The perchloric acid dehydration gravimetric method for the
determination of silicon content
GB/T 223.61 - 1988 Methods for chemical analysis of iron, steel and alloy
― The determination of phosphorus content by ammonium
molybdo-phosphate volumetric method
GB/T 223.62 - 1988 Methods for chemical analysis of iron, steel and alloy
― The determination of phosphorus content by butyl acetate
extraction photometric method
GB/T 223.63 - 1988 Methods for chemical analysis of iron, steel and alloy
― The determination of manganese content by sodium (potassium)
permanganate photometric method
GB/T 223.64 - 1988 Methods for chemical analysis of iron, steel and alloy
― The determination of manganese content by flame atomic
absorption spectrometric method
GB/T 223.67 - 1989 Methods for chemical analysis of iron, steel and alloy
― The determination of sulfur content methylidyne blue photometric
method after reduced distillation
GB/T 223.68 - 1997 Methods for chemical analysis of iron, steel and alloy
― The potassium iodate titration method after combustion in the pipe
furnace for the determination of sulfur content
GB/T 223.69 - 1997 Methods for chemical analysis of iron, steel and alloy
― The gas-volumetric method after combustion in the pipe furnace
for the determination of carbon content
GB/T 223.71 - 1997 Methods for chemical analysis of iron, steel and alloy
― The volumetric method after combustion in the pipe furnace for the determination
of carbon content
GB/T 223.72 - 1991 Methods for chemical analysis of iron, steel and alloy
― Aluminum oxide stratography - barium sulfate gravimetric method
for the determination of sulfur content

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