ASTM A400-69(2012)

Standard Practice for Steel Bars, Selection Guide, Composition, and Mechanical Properties

SIGNIFICANCE AND USE
If the desired mechanical properties are as described in 4.1.1 for material identified as Classes P-1 through P-7, or in 4.1.2 for material identified as Classes Q-1 through Q-7, the strength level desired can be based on hardness or the equivalent tensile or yield strength as shown in Tables 1-4. If the desired mechanical properties are as set forth in 4.1.3 for material identified as Classes R-1 through R-6, the strength level is based on yield strength as shown in Tables 5 and 6.  
The user, after determining the mechanical property requirements of the critical section (that carrying the greatest stress) of the part, should select the composition or compositions from Tables 1-6 that fulfills these requirements and is most suitable for processing.
SCOPE
1.1 This practice covers the selection of steel bars according to section and to the mechanical properties desired in the part to be produced. This is not a specification for the procurement of steel. Applicable procurement specifications are listed in Section 5.  
1.2 Several steel compositions intended for various sections and mechanical property requirements are presented in Tables 1-6. The criteria for placing a steel composition in one of the three general class designations, Classes P, Q, and R (described in Section 4) are as follows:  
1.2.1 Classes P and Q should be capable of developing the mechanical properties shown in Tables 1-4 by liquid quenching from a suitable austenitizing temperature, and tempering at 800°F (427°C) or higher. A hardness indicated by tests made at a location shown in Fig. 1, A, B, or C, is taken as evidence that a composition is capable of meeting other equivalent mechanical properties shown in the tables. Normal good shop practices are assumed, with control of austenitizing and tempering temperatures, and mild agitation of the part in the quenching bath.
1.2.2 Class R should be capable of developing the mechanical properties shown in Tables 5 and 6 as hot rolled, by cold drawing, or by cold drawing with additional thermal treatment. The locations for obtaining tension tests are described in 6.2.  
1.3 It is not implied that the compositions listed in the tables are the only ones satisfactory for a certain class and mechanical property requirement. Steels with lower alloy contents are often satisfactory through the use of special processing techniques.  
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
TABLE 1 Steels for Moderately Quenched PartsClasses P-1 Through P-7
(Applicable to oil-quenching or equivalent rate of heat-removal.)
Note 1—Steels listed as approved for a certain section or strength may be used for lighter sections and lower strengths.
Note 2—Steel composition numbers correspond to SAE, AISI, or ASTM designations. Those in italics are no longer considered standard grades due to decreased usage.
Note 3—An H-steel with the same grade designation as a standard SAE-AISI steel is capable of meeting the same section and strength requirements as the standard steel (see Specification A304), and is the preferred method of specification.
Note 4—Steels having a maximum carbon content of 0.40 % or over, or a hardness of HB 293 or over after heat-treating, are not recommended for applications involving welding.   Desired Minimum
Hardness
  Equivalent
Tensile
Strength, psiA
  Equivalent
Yield
Strength, psiA
MinimumB
As-Quenched
Hardness
Class P-1
P-2
P-3
P-4
  P-5
P-6
  P-7
  Diameter of Round (or Distance Between Faces of Square
or Hexagonal) Sections, in.C
  To ½, incl  Over ½ to 1, incl Over 1 to 11/2, incl  Over 1½ to 2, inclOver 2 to 21/2, incl Over 2½ to 3, incl Over 3 to 31/2, incl Thickness of Flat Sections, in.C
  HBHRC
  HB
HRC
To 0.3, incl
Over 0.3 to 0.6, incl
Ove...

General Information

• Status: Historical
• Publication Date: 29-Feb-2012
• ICS: 77.140.60 - Steel bars and rods
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.15 - Bars

Relations

• Replaces: ASTM A400-69(2006) - Standard Practice for Steel Bars, Selection Guide, Composition, and Mechanical Properties
• Effective Date: 01-Mar-2012
• Replaced By: ASTM A400-17 - Standard Practice for Steel Bars, Selection Guide, Composition, and Mechanical Properties
• Effective Date: 01-Nov-2017
• Referred By: ASTM A576-17 - Standard Specification for Steel Bars, Carbon, Hot-Wrought, Special Quality
• Effective Date: 01-Mar-2012
• Referred By: ASTM A322-13(2018)e1 - Standard Specification for Steel Bars, Alloy, Standard Grades
• Effective Date: 01-Mar-2012
• Referred By: ASTM A108-18 - Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
• Effective Date: 01-Mar-2012

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: A400 − 69 (Reapproved 2012)
Standard Practice for
Steel Bars, Selection Guide, Composition, and Mechanical
Properties
This standard is issued under the fixed designation A400; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope 2. Referenced Documents
1.1 This practice covers the selection of steel bars according 2.1 ASTM Standards:
to section and to the mechanical properties desired in the part A108 Specification for Steel Bar, Carbon and Alloy, Cold-
to be produced. This is not a specification for the procurement Finished
of steel. Applicable procurement specifications are listed in A304 Specification for Carbon andAlloy Steel Bars Subject
Section 5. to End-Quench Hardenability Requirements
A311/A311M Specification for Cold-Drawn, Stress-
1.2 Several steel compositions intended for various sections
Relieved Carbon Steel Bars Subject to Mechanical Prop-
and mechanical property requirements are presented in Tables
erty Requirements
1-6. The criteria for placing a steel composition in one of the
A322 Specification for Steel Bars, Alloy, Standard Grades
three general class designations, Classes P, Q, and R (described
A633/A633M Specification for Normalized High-Strength
in Section 4) are as follows:
Low-Alloy Structural Steel Plates
1.2.1 Classes P and Q should be capable of developing the
A675/A675M Specification for Steel Bars, Carbon, Hot-
mechanicalpropertiesshowninTables1-4byliquidquenching
Wrought, Special Quality, Mechanical Properties
from a suitable austenitizing temperature, and tempering at
800°F (427°C) or higher.Ahardness indicated by tests made at
3. Significance and Use
a location shown in Fig. 1,A, B, or C, is taken as evidence that
3.1 If the desired mechanical properties are as described in
a composition is capable of meeting other equivalent mechani-
4.1.1 for material identified as Classes P-1 through P-7, or in
cal properties shown in the tables. Normal good shop practices
4.1.2 for material identified as Classes Q-1 through Q-7, the
are assumed, with control of austenitizing and tempering
strength level desired can be based on hardness or the
temperatures, and mild agitation of the part in the quenching
equivalent tensile or yield strength as shown in Tables 1-4.If
bath.
the desired mechanical properties are as set forth in 4.1.3 for
1.2.2 Class R should be capable of developing the mechani-
material identified as Classes R-1 through R-6, the strength
cal properties shown in Tables 5 and 6 as hot rolled, by cold
level is based on yield strength as shown in Tables 5 and 6.
drawing, or by cold drawing with additional thermal treatment.
The locations for obtaining tension tests are described in 6.2.
3.2 The user, after determining the mechanical property
requirements of the critical section (that carrying the greatest
1.3 Itisnotimpliedthatthecompositionslistedinthetables
stress) of the part, should select the composition or composi-
aretheonlyonessatisfactoryforacertainclassandmechanical
tions from Tables 1-6 that fulfills these requirements and is
property requirement. Steels with lower alloy contents are
most suitable for processing.
often satisfactory through the use of special processing tech-
niques.
4. Classification
1.4 The values stated in inch-pound units are to be regarded
4.1 Steel bar compositions under this practice are classified
as standard. The values given in parentheses are mathematical
according to mechanical property requirements and the critical
conversions to SI units that are provided for information only
section size of the part to be produced, as follows:
and are not considered standard.
4.1.1 Classes P-1 through P-7 comprise bars for parts to
operate under severe service conditions requiring high yield
This practice is under the jurisdiction of ASTM Committee A01 on Steel,
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee
A01.15 on Bars. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved March 1, 2012. Published April 2012. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1956. Last previous edition approved in 2006 as A400 – 69 (2006). Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/A0400-69R12. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A400 − 69 (2012)
TABLE 1 Steels for Moderately Quenched Parts—Classes P-1 Through P-7
(Applicable to oil-quenching or equivalent rate of heat-removal.)
NOTE 1—Steels listed as approved for a certain section or strength may be used for lighter sections and lower strengths.
NOTE 2—Steel composition numbers correspond to SAE, AISI, or ASTM designations. Those in italics are no longer considered standard grades due
to decreased usage.
NOTE 3—An H-steel with the same grade designation as a standard SAE-AISI steel is capable of meeting the same section and strength requirements
as the standard steel (see Specification A304), and is the preferred method of specification.
NOTE 4—Steels having a maximum carbon content of 0.40 % or over, or a hardness of HB 293 or over after heat-treating, are not recommended for
applications involving welding.
Class
P-1 P-2 P-3 P-4 P-5 P-6 P-7
Diameter of Round (or Distance Between Faces of Square
B
Equivalent Equivalent
Minimum C
Desired Minimum or Hexagonal) Sections, in.
Tensile Yield As-Quenched
1 1 1 1
Hardness To ⁄2, incl Over ⁄2 to 1, Over 1 to Over 1 ⁄2 Over 2 to Over 2 ⁄2 Over 3
A A
Hardness
Strength, psi Strength, psi
1 1 1
incl 1 ⁄2, incl to 2, incl 2 ⁄2, incl to 3, incl to 3 ⁄2,
incl
C
Thickness of Flat Sections, in.
To 0.3, incl Over 0.3 to Over 0.6 Over 1 Over 1.3 Over 1.6 Over 2.0
HB HRC HB HRC 0.6, incl to 1, to 1.3, to 1.6, to 2.0, to 2.3,
incl incl incl incl incl
229 to 293, 20 to 33, 110 000 to 90 000 to 388 42 1330
incl incl 145 000, 125 000, 4130 50B30
incl incl 5132
Over 293 Over 33 Over 145 000 Over 125 000 409 44 1335 94B30 3140 4137 4142 9840 4337
to 341, to 38, to 170 000, to 150 000, 3135 4135
incl incl incl incl 4042 4640
5135 8640
Over 341 Over 38 Over 170 000 Over 150 000 455 48 1340 4137 4140 4145 4147 4340
to 388, to 42, to 190 000, to 170 000, 3140 6145 TS4140 9840 4337
incl incl incl incl
4047 8642 86B45
4135 8645 94B40
5140 8742
TS14B50
50B40
Over 388 to Over 42 Over 190 000 Over 496 51 1345 8645 5147 4142 8660 4147 4150 E4340
429, incl to 45, to 205 000, 170 000 4063 8740 5155 4145 9840 4161 4161 9850
incl incl to 185 000, 4068 8742 5160 4337 4340 TS4150
incl
4140 9260 6150 8650 86B45
4640 9261 9262 8655
5145 TS4140 50B60
5150 50B46 94B40 51B60
8640 50B44 81B45
8642 50B50
A
1 psi = 0.006895 MPa.
B
Minimum as-quenched hardness for obtaining desired hardness after tempering at 800°F (427°C) or higher.
C
1 in. = 25.4 mm.
strength (90 000 psi (621 MPa) and over), good ductility, and to 827 MPa)), with fair to good ductility. The applicable
relatively high notch toughness. The applicable section sizes, section sizes, identified as Classes R-1 through R-6, are shown
identified as Classes P-1 through P-7, are shown in Table 7. in Table 7. The steel compositions capable of developing the
The steel compositions suitable for Classes P-1 through P-7 various desired mechanical properties are listed inTables 5 and
and for various desired mechanical properties are listed in 6.
Tables 1 and 2.
5. Applicable Procurement Specifications
4.1.2 Classes Q-1 through Q-7 comprise bars for parts
operating under moderate service conditions requiring moder- 5.1 For procurement of steel, it is recommended that the
ate to high yield strength (75 000 to 185 000 psi (517 to 1276 following ASTM specifications of latest issue be used: Speci-
MPa)), corresponding tensile-strength levels, and good ductil- fication A108, Specification A304, Specification A311/
ity. The applicable section sizes, identified as Classes Q-1 A311M, Specification A322, Specification A633/A633M, and
through Q-7, are shown in Table 7. The steel compositions Specification A675/A675M.
suitable for Classes Q-1 through Q-7 and various desired
6. Location at Which Desired Properties Are Obtained
mechanical properties are listed in Tables 3 and 4.
4.1.3 Classes R-1 through R-6 comprise bars for parts 6.1 Classes P-1 Through P-7 and Q-1 Through Q-7—The
requiring a lower yield strength (30 000 to 120 000 psi (207 mechanical properties shown in Tables 1-4 are based on
A400 − 69 (2012)
TABLE 2 Steels for Drastically Quenched Parts—Classes P-1 Through P-7
(Applicable to water-quenching or equivalent rate of heat-removal — See Note 5)
NOTE 1—Steels listed as approved for heavier sections or higher strengths may be used in the same conditions for lighter sections and lower strengths.
NOTE 2—Steel composition numbers correspond to ASE, AISI, or ASTM designations. Those in italics are no longer considered standard grades due
to decreased usage.
NOTE 3—An H-steel with the same grade designation as a standard SAE-AISI steel is capable of meeting the same section and strength requirements
as the standard steel (see Specification A304), and is the preferred method of specification.
NOTE 4—Steels having a maximum carbon content of 0.40 % or over, or a hardness of HB 293 or over after heat-treating, are not recommended for
applications involving welding.
NOTE 5—Parts made of steel with a carbon content of 0.33 % or higher, where the section is under 1 1/2 in. (38.1 mm) should not be quenched in
water without careful exploration for quench-cracking.
Class
P-1 P-2 P-3 P-4 P-5 P-6 P-7
Diameter of Round (or Distance Between Faces of Square
B
Equivalent Equivalent
Minimum C
Desired Minimum or Hexagonal) Sections, in.
Tensile Yield As-Quenched
1 1
Hardness To ⁄2 , incl Over Over 1 to Over Over 2 Over 2 ⁄2 Over 3
A A
Hardness
Strength, psi Strength, psi
1 1 1 1 1
⁄2 to 1, 1 ⁄2, incl 1 ⁄2 to to 2 ⁄2, to 3, incl to 3 ⁄2,
incl 2, incl incl incl
C
Thickness of Flat Sections, in.
HB HRC HB HRC To 0.3, incl Over 0.3 Over 0.6 Over Over 1.3 Over 1.6 Over 2.0
to 0.6, to 1.0, 1.0 to 1.6, to 2.0, to 2.3,
incl incl to 1.3, incl incl incl
incl
229 to 293, 20 to 33, 110 000 to 90 000 to 388 42 8625 4130 94B30
incl incl 145 000, 125 000, 8627 5130
incl incl 8630
50B30
D
Over 293 Over 33 Over 145 000 Over 125 000 409 44 4032 1330 1335 1340 3140 4137
D
to 341, to 38, to 170 000, to 150 000, 4037 5132 5135 3135 4135 4337
incl incl incl incl 4130 94B30 5140 4640 9840
D
5130 50B40 8637
8630 8640
TS14B35 8740
508B30
A
1 psi = 0.006895 MPa.
B
Minimum as-quenched hardness for obtaining desired hardness after tempering at 800°F (427°C) or higher.
C
1 in. = 25.4 mm.
D
These steels have insufficient hardenability for Class P-4, because of difference in test locations, but are satisfactory for other smaller sizes.
obtaining hardness test specimens from the locations shown in 7. Hardness Criteria for Quenched and Tempered Parts
Fig. 1, A, B, and C. For bars, the location should be at least
7.1 Classes Q-1 Through Q-7—To obtain the properties
twicethediameterorminimumdistancebetweenfacesfroman
stated in 4.1.2 at the locations shown in Fig. 1, A, B, and C, a
end; and for flat sections, at least twice the thickness from an
microstructure containing a minimum of 50 % martensite is
edge.
necessary.
6.2 Classes R-1 Through R-6—The mechanical properties
shown in Tables 5 and 6 are based on obtaining tension test
8. Keywords
specimens from the following locations:
8.1 steel bars
6.2.1 Center of bars or plates under 1 ⁄2 in. (38.1 mm) in
diameter or in distance between parallel surfaces, and
6.2.2 Mid-radius or a quarter of the distance between
parallel faces from the surface for larger sections.
A400 − 69 (2012)
TABLE 3 Steels for Moderately Quenched Parts—Classes Q-1 Through Q-7
(Applicable to oil-quenching or equivalent rate of heat-removal.)
NOTE 1—Steels listed as approved for heavier sections or higher strengths may be used in the same conditions for lighter sections and lower strengths.
NOTE 2—Steel composition numbers correspond to ASE, AISI, or ASTM designations. Those in italics are no longer considered standard grades due
to decreased usage.
NOTE 3—An H-steel with the same grade designation as a standard SAE-AISI steel is capable of meeting the same section and strength requirements
as the standard steel (see Specification A304), and is the preferred method of specification.
NOTE 4—Steels having a maximum carbon content of 0.40 % or over, or a hardness of HB 293 or over after heat-treating, are not recommended for
applications involving welding.
Class
Q-1 Q-2 Q-3 Q-4 Q-5 Q-6 Q-7
Diameter of Round (or Distance Between Faces of Square
B
Equivalent Equivalent
C
Minimum
or Hexagonal) Sections, in.
Desired Minimum Tensile Yield
As-
Quenched Over
Hardness Strength, Strength,
1 1
Over ⁄2 Over 1 Over 2 Over 2 ⁄2 Over 3
A A Hardness
1 ⁄2
psi psi
1 1 1 1
To ⁄2, incl to 1, to 1 ⁄2, to 2 ⁄2, to 3, to 3 ⁄2,
to 2,
incl incl incl incl incl
incl
C
Thickness of Flat Sections, in.
Over 0.6 Over 1.0 Over 1.3 Over 1.6 Over 2.0
Over 0.3 to 0.6,
HB HRC HB HRC To 0.3, incl to 1.0, to 1.3, to 1.6, to 2.0, to 2.3,
incl
incl incl incl incl incl
187 to 293, 91 (R ) 95 000 to 75 000 to 388 42 1330 8630 8637 3140 4140 4142
b
incl to 33, 145 000, 125 000, 4130 50B30 8740 TS4140
incl incl incl 5132 94B40
Over 293 Over 33 Over Over 409 44 1335 3140 8740 4137 TS4140 81B45 4142 4145 4147
to 341, to 38, 145 000 125 000 4042 50B30 4135 4140 4337
incl incl to to 5135 4640 8642 9840
170 000, 150 000, 94B30 8640 8645 86B45
incl incl 8742
Over 341 Over 38 Over Over 455 48 1340 8637 1345 8742 4142 94B40 51B60 4145 4147 4150
to 388, to 42, 170 000 150 000 3135 TS14B504137 TS4140 5147 8655 4337 4340
incl incl to to 3140 50B40 4140 50B50 5155 9840 86B45 TS4150
190 000, 170 000, 4047 5150 6150
incl incl 4135 8642
5140 8645
Over 388 Over 42 Over Over 496 51 1345 8645 4142 4145 9840 4147 4150 E4340
to 429, to 45, 190 000 170 000 4047 8740 5147 4337 4340 TS4150 9850
incl incl to to 4063 8742 5155 5160 8660
205 000, 185 000, 4068 9260 6150 8650 86B45
incl incl 4140 TS4140 9261 8655
4640 50B46 94B40 9262
5145 50B44 50B60
5150 50B50 51B60
8640 81B45
A
1 psi = 0.006895 MPa.
B
Minimum as-quenched hardness for obtaining desired hardness after tempering at 800°F (427°C) or higher.
C
1 in. = 25
...