1.1This specification covers carbon and high-strength low-alloy steel structural shapes, plates, and bars and quenched and tempered alloy steel for structural plates intended for use in bridges. Seven grades are available in four yield strength levels as follows:
Grade U.S. [SI] | Yield Strength, ksi [MPa] |
36 [250] | 36 [250] |
50 [345] | 50 [345] |
50S [345S] | 50 [345] |
50W [345W] | 50 [345] |
HPS 50W [HPS 345W] | 50 [345] |
HPS 70W [HPS 485W] | 70 [485] |
HPS 100W [HPS 690W] | 100 [690] |
1.1.1Grades 36 [250], 50 [345], 50S [345S], and 50W [345W] are also included in Specifications A36/A36M, A572/A572M, A992/A992M, and A588/A588M, respectively. When the requirements of Table 8 or Table 9 or the supplementary requirements of this specification are specified, they exceed the requirements of Specifications A36/A36M, A572/A572M, A992/A992M, and A588/A588M.
1.1.2Grades 50W [345W], HPS 50W [HPS 345W], HPS 70W [HPS 485W], and HPS 100W [HPS 690W] have enhanced atmospheric corrosion resistance (see 13.1.2). Product availability is shown in Table 1.
TABLE 1 Tensile and Hardness RequirementsA Note 1—
Where “. . .” appears in this table, there is no requirement. Grade
| Plate Thickness, in. [mm] | Structural Shape Flange or Leg Thickness, in. [mm] | Yield Point or Yield Strength,B ksi [MPa] | Tensile Strength, ksi [MPa]
| Minimum Elongation, %
| Reduc- tion of AreaC,D min, %
|
Plates and BarsC,E
| ShapesE
|
8 in. or 200 mm | 2 in. or 50 mm | 8 in. or 200 mm | 2 in. or 50 mm
|
36 [250] | to 4 [100], incl | to 3 in. [75 mm], incl | 36 [250] min | 58–80 [400–550]
| 20 | 23 | 20 | 21 | ...
|
| | over 3 in. [75 mm]
| 36 [250] min | 58 [400] min
| ...
| .. | 20 | 19 | ... |
50 [345]
| to 4 [100], incl | all | 50 [345] min | 65 [450] min
| 18 | 21 | 18 | 21F | ...
|
50S [345S] | G | all | 50–65 [345–450]HI | 65 [450]H min | ...
| ... | 18 | 21 | ...
|
50W [345W] and HPS 50W [HPS 345W]
| to 4 [100], incl
| all | 50 [345] min | 70 [485] min
| 18
| 21 | 18 | 21J | ... |
HPS 70W [HPS 485 W]
| to 4 [100], incl | G | 70 [485] minB | 85–110 [585–760] | ...
| 19K | ...
| ...
| ...
|
HPS 100W [HPS 690W] | to 21/2[65], incl
| G | 100 [690] minB | 110–130 [760–895]
| ... | 18K
| ... | ...
| L |
| over 21/2to 4 [65 to 100], inclM | G | 90 [620] minB | 100–130 [690–895]
| ... | 16K
| ... | ...
| L
|
TABLE 2 Grade 36 [250] Chemical Requirements (Heat Analysis)
Note 1—
Where “. . .” appears in this table there is no requirement. The heat analysis for manganese shall be determined and reported as described in the Heat Analysis section of Specification A6/A6M. Product Thickness, in. (mm)
| ShapesA All
| PlatesB
| BarsB
|
To 3/4 [20], incl | Over 3/4 to 11/2[20 to 40], incl | Over 11/2to 21/2[40 to 65], incl | Over 21/2to 4 [65 to 100], incl | To 3/4 [20], incl | Over 3/4to 11/2[20 to 40], incl | Over 11/2to 4 [100], incl |
|
Carbon, max, %
| 0.26
| 0.25
| 0.25
| 0.26
| 0.27
| 0.26
| 0.27
| 0.28
|
Manganese, %
| ...
| ...
| 0.80–1.20
| 0.80–1.20
| 0.85–1.20
| ...
| 0.60–0.90
| 0.60–0.90
|
Phosphorus, max, % | 0.04
| 0.04
| 0.04
| 0.04
| 0.04 | 0.04
| 0.04
| 0.04
|
Sulfur, max, % | 0.05
| 0.05
| 0.05
| 0.05
| 0.05 | 0.05
| 0.05
| 0.05
|
Silicon, % | 0.40 max
| 0.40 max
| 0.40 max | 0.15–0.40
| 0.15–0.40 | 0.40 max
| 0.40 max
| 0.40 max |
Copper, min, % when copper steel is specified
| 0.20
| 0.20
| 0.20 | 0.20
| 0.20
| 0.20
| 0.20 | 0.20 |
TABLE 3 Grade 50 [345] Chemical RequirementsA (Heat Analysis)
| | | | | SiliconC | Columbium, Vanadium and Nitrogen |
Maximum Diameter, Thickness, or Distance Between Parallel Faces, in. [mm]
| Carbon, max, % | Manganese,B max, % | Phosphorus, max, % | Sulfur, max, % | Plates to 11/2-in. [40-mm] Thick, Shapes with flange or leg thickness to 3 in. [75 mm] inclusive, Sheet Piling, Bars, Zees, and Rolled Tees, max, %D | Plates Over 11/2-in. [40-mm] Thick and Shapes with flange thickness over 3 in. [75 mm], % | |
4 [100] | 0.23 | 1.35 | 0.04 | 0.05 | 0.40 | 0.15–0.40 | E |
A Copper when specified shall have a minimum content of 0.20 % by heat analysis (0.18 % by product analysis). |
B Manganese, minimum by heat analysis of 0.80 % (0.75 % by product analysis) shall be required for all plates over 3/8in. [10 mm] in thickness; a minimum of 0.50 % (0.45 % by product analysis) shall be required for plates 3/8in. [10 mm] and less in thickness, and for all other products. The manganese to carbon ratio shall not be less than 2 to 1. For each reduction of 0.01 percentage point below the specified carbon maximum, an increase of 0.06 percentage point manganese above the specified maximum is permitted, up to a maximum of 1.60 %. |
C Silicon content in excess of 0.40 % by heat analysis must be negotiated. |
D Bars over 11/2in. [40 mm] in diameter, thickness, or distance between parallel faces, shall be made by a killed steel practice. |
E Alloy content shall be in accordance with Type 1, 2, 3, or 5 and the contents of the applicable elements shall be reported on the test report. |
Type | Elements | Heat Analysis, % |
1 | ColumbiumA | 0.005–0.05B |
2 | Vanadium | 0.01–0.15 |
3 | ColumbiumA Vanadium Columbium plus vanadium | 0.005–0.05B 0.01–0.15 0.02–0.15C |
5 | Titanium Nitrogen Vanadium | 0.006–0.04 0.003–0.015 0.06 max |
TABLE 4 Grade 50W [345 W] Chemical Requirements (Heat Analysis)
Note 1—
Types A and B are equivalent to Specification A588/A588M, Grades A and B, respectively. Element
| Composition, %A |
Type A | Type B |
|
CarbonB | 0.19 max | 0.20 max |
ManganeseB | 0.80–1.25 | 0.75–1.35 |
Phosphorus | 0.04 max | 0.04 max |
Sulfur | 0.05 max | 0.05 max |
Silicon | 0.30–0.65 | 0.15–0.50 |
Nickel | 0.40 max | 0.50 max |
Chromium | 0.40–0.65 | 0.40–0.70 |
Copper | 0.25–0.40 | 0.20–0.40 |
Vanadium | 0.02–0.10 | 0.01–0.10 |
TABLE 5 Grades HPS 50W [HPS 345W] and HPS 70W [HPS 485 W], and HPS 100W [HPS 690W] Chemical Requirements (Heat Analysis)
Note 1—
Where “. . .” appears in this table, there is no requirement. Element | Composition, % |
Grades HPS 50W [HPS 345W], HPS 70W [HPS 485W] | Grade HPS 100W [HPS 690W] |
Carbon | 0.11 max | 0.08 max |
Manganese | | |
2.5 in. [65 mm] and under | 1.10–1.35 | 0.95–1.50 |
Over 2.5 in. [65 mm] | 1.10–1.50 | 0.95–1.50 |
Phosphorus | 0.020 max | 0.015 max |
SulfurA | 0.006 max | 0.006 max |
Silicon | 0.30–0.50 | 0.15–0.35 |
Copper | 0.25–0.40 | 0.90–1.20 |
Nickel | 0.25–0.40 | 0.65–0.90 |
Chromium | 0.45–0.70 | 0.40–0.65 |
Molybdenum | 0.02–0.08 | 0.40–0.65 |
Vanadium | 0.04–0.08 | 0.04–0.08 |
Columbium (Niobium) | . . . | 0.01–0.03 |
Aluminum | 0.010–0.040 | 0.020–0.050 |
Nitrogen | 0.015 max | 0.015 max |
TABLE 6 Grade 50S [345S] Chemical Requirements (Heat Analysis)
Element | Composition, % |
|
| Carbon, max | 0.23 |
| Manganese | 0.50 to 1.60A |
| Silicon, max | 0.40 |
| Vanadium, max | 0.15B |
| Columbium, max | 0.05B |
| Phosphorus, max | 0.035 |
| Sulfur, max | 0.045 |
| Copper, max | 0.60 |
| Nickel, max | 0.45 |
| Chromium, max | 0.35 |
| Molybdenum, max | 0.15 |
TABLE 7 Relationship Between Impact Testing Temperature Zones and Minimum Service Temperature
Zone
| Minimum Service Temperature, °F [°C]
|
|
1 | 0 | [−18] |
2 | below 0 to −30 | [−18 to −34] |
3 | below −30 to −60 | [−34 to −51] |
1.2Grade HPS 70W [HPS 485W] or HPS 100W [HPS 690W] shall not be substituted for Grades 36 [250], 50 [345], 50S [345S], 50W [345W], or HPS 50W [HPS 345W]. Grade 50W [345W], or HPS 50W [HPS 345W] shall not be substituted for Grades 36 [250], 50 [345] or 50S [345S] without agreement between the purchaser and the supplier.
1.3When the steel is to be welded, it is presupposed that a welding procedure suitable for the grade of steel and intended use or service will be utilized. See Appendix X3 of Specification A6/A6M for information on weldability.
1.4For structural products to be used as tension components requiring notch toughness testing, standardized requirements are provided in this standard, and they are based upon American Association of State Highway and Transportation Officials (AASHTO) requirements for both fracture critical and non-fracture critical members.
1.5Supplementary requirements are available but shall apply only if specified in the purchase order.
1.6The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.
1.7For structural products produced from coil and furnished without heat treatment or with stress relieving only, the additional requirements, including additional testing requirements and the reporting of additional test results, of Specification A6/A6M apply.