ASTM A27/A27M-20

Standard Specification for Steel Castings, Carbon, for General Application

ABSTRACT
This specification covers carbon steel castings for general applications. The grades of steels covered here are: Grade N-1, Grade N-2, Grade U-60-30 [415-205], Grade 60-30 [415-205], Grade 65-35 [450-240], Grade 70-36 [485-250] and Grade 70-40 [485-275]. Except for Grades N-1 and U-60-30, all steel castings shall be heat-treated by full annealing, normalizing, normalizing and tempering, or quenching and tempering. Heat treatments shall be performed after castings have been allowed to cool. Heat and product analyses shall be performed wherein specimens shall conform to required chemical composition of carbon, manganese, silicon, sulfur and phosphorus. Except for Grades N-1 and N-2, all steels shall undergo tension test, and shall conform to the following mechanical requirements: tensile strength, yield point, elongation, and reduction of area.
SCOPE
1.1 This specification covers carbon steel castings for general applications that require up to 70 ksi (485 MPa) minimum tensile strength.  
Note 1: The grades covered by this specification represent materials that are suitable for assembly with other steel castings or wrought steel parts by fusion welding. It is not intended to imply that all these grades possess the same degree of weldability or that the same welding techniques can be used on all castings. It is the responsibility of the purchaser to establish for himself a suitable welding technique.  
1.2 Several grades and two classes of steel castings are covered, as indicated below. The grade and class desired shall be specified by the purchaser.  
1.2.1 Grade N-1—Chemical analysis only.  
1.2.2 Grade N-2—Heat treated but not mechanically tested.  
1.2.3 Grade U-60-30 [415-205]—Mechanically tested but not heat treated.  
1.2.4 Grades 60-30  [415-205], 65-35 [450-240], 70-36 [485-250], and 70-40 [485-275]—Heat treated and mechanically tested.  
1.2.5 Class 1 and Class 2 steel castings shall be specified in accordance with 9.2.  
1.3 The 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 nonconformance with the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Apr-2020
• ICS: 77.140.80 - Iron and steel castings
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.18 - Castings

Relations

• Replaces: ASTM A27/A27M-19 - Standard Specification for Steel Castings, Carbon, for General Application
• Effective Date: 01-May-2020
• Refers: ASTM A957/A957M-18a - Standard Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Sep-2018
• Refers: ASTM A781/A781M-18c - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Sep-2018
• Refers: ASTM A781/A781M-18b - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Jun-2018
• Refers: ASTM A957/A957M-18 - Standard Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 15-May-2018
• Refers: ASTM A781/A781M-18a - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 15-May-2018
• Refers: ASTM A781/A781M-18 - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Jan-2018
• Refers: ASTM A781/A781M-17 - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-May-2017
• Refers: ASTM A781/A781M-16 - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Dec-2016
• Refers: ASTM A957/A957M-15a - Standard Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Nov-2015
• Refers: ASTM A957/A957M-15 - Standard Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Mar-2015
• Refers: ASTM A781/A781M-14b - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Oct-2014
• Refers: ASTM A957/A957M-14 - Standard Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Oct-2014
• Refers: ASTM A781/A781M-14a - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-May-2014
• Refers: ASTM A781/A781M-14 - Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
• Effective Date: 01-Mar-2014

Overview

ASTM A27/A27M-20 is the internationally recognized standard specification developed by ASTM for carbon steel castings intended for general applications. This standard sets out the requirements for the manufacture, heat treatment, chemical composition, and testing of steel castings with specified grades and classes, ensuring reliable performance under various operational conditions. The specification is widely referenced by engineers, manufacturers, and quality assurance professionals working with steel castings for structural and mechanical components.

Key Topics

• Scope and Grades
  ASTM A27/A27M-20 covers several grades of carbon steel castings, ranging from lower carbon Grade N-1 to higher-strength grades like 70-36 [485-250] and 70-40 [485-275]. Each grade is suited for specific mechanical properties, such as minimum tensile strength up to 70 ksi (485 MPa).

• Heat Treatment Requirements
  Most steel castings, except certain grades, must undergo heat treatments including annealing, normalizing, normalizing and tempering, or quenching and tempering, to ensure desired mechanical properties and structural integrity.

• Chemical and Mechanical Properties
  The standard requires castings to meet strict requirements for chemical composition-including carbon, manganese, silicon, sulfur, and phosphorus content-as well as mechanical properties such as tensile strength, yield strength, elongation, and reduction of area. Comprehensive testing ensures compliance and product consistency.

• Classes
  Two classes are specified:

  • Class 1: Post-weld heat treatment required.
  • Class 2: Post-weld heat treatment not required.

• Testing and Quality Assurance
  Regular heat and product analyses, tension tests, and supplementary evaluations (such as magnetic particle, radiographic, and ultrasonic testing) help maintain casting quality.

Applications

ASTM A27/A27M-20 is extensively used across industries requiring robust carbon steel castings for general applications. Typical applications include:

• Structural Components: Beams, brackets, and supports in construction and civil engineering projects.
• Mechanical Equipment: Parts for pumps, valves, gears, and frames.
• Industrial Machinery: Heavy-duty components for manufacturing equipment and processing lines.
• Fusion Welding Assemblies: The material is suitable for fusion welding with other steel castings or wrought steel parts, though proper welding techniques must be selected by the purchaser.

The versatility of applicable grades and mechanical characteristics allow users to select castings that closely match project requirements for strength, ductility, and reliability.

Related Standards

Implementing ASTM A27/A27M-20 often requires reference to these key related ASTM standards:

• ASTM A781/A781M: General requirements for steel and alloy castings for industrial use.
• ASTM A957/A957M: Specifications for investment castings of steel and alloys.
• Testing Standards: Supplementary requirements reference standard testing procedures for non-destructive examinations (e.g., magnetic particle, radiographic, liquid penetrant, and ultrasonic exams).

Practical Value

Using ASTM A27/A27M-20 ensures carbon steel castings meet globally recognized criteria for quality, performance, and safety. This benefits manufacturers aiming for consistent output and end-users seeking assurance of material reliability. The standard’s flexibility accommodates diverse project specifications by offering different grades and classes, supporting optimal selection for fusion welding and mechanical performance needs. The embedded quality assurance processes help minimize risk while maximizing product longevity and compliance.

Keywords: ASTM A27/A27M-20, carbon steel castings, steel castings specification, general application castings, heat treatment, tensile strength, mechanical properties, casting standards, welding, industrial castings.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:A27/A27M −20
Standard Specification for
Steel Castings, Carbon, for General Application
This standard is issued under the fixed designation A27/A27M; 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* ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
1.1 This specification covers carbon steel castings for gen-
mendations issued by the World Trade Organization Technical
eral applications that require up to 70 ksi (485 MPa) minimum
Barriers to Trade (TBT) Committee.
tensile strength.
NOTE 1—The grades covered by this specification represent materials 2. Referenced Documents
that are suitable for assembly with other steel castings or wrought steel
2.1 ASTM Standards:
parts by fusion welding. It is not intended to imply that all these grades
A781/A781M Specification for Castings, Steel and Alloy,
possess the same degree of weldability or that the same welding
techniques can be used on all castings. It is the responsibility of the
Common Requirements, for General Industrial Use
purchaser to establish for himself a suitable welding technique.
A957/A957M Specification for Investment Castings, Steel
1.2 Several grades and two classes of steel castings are and Alloy, Common Requirements, for General Industrial
covered, as indicated below. The grade and class desired shall Use
be specified by the purchaser.
3. General Conditions for Delivery
1.2.1 Grade N-1—Chemical analysis only.
1.2.2 Grade N-2—Heat treated but not mechanically tested.
3.1 Except for steel investment castings, material furnished
1.2.3 Grade U-60-30 [415-205]—Mechanically tested but
to this specification shall conform to the requirements of
not heat treated.
Specification A781/A781M, including any supplementary re-
1.2.4 Grades 60-30 [415-205], 65-35 [450-240], 70-36
quirements that are indicated in the purchase order. Failure to
[485-250], and 70-40 [485-275]—Heat treated and mechani-
comply with the general requirements of Specification A781/
cally tested.
A781M constitutes nonconformance with the specification. In
1.2.5 Class 1 and Class 2 steel castings shall be specified in
caseofaconflictbetweentherequirementsofthisspecification
accordance with 9.2.
and Specification A781/A781M, this specification shall pre-
vail.
1.3 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. The values stated in
3.2 Steel investment castings furnished to this specification
each system may not be exact equivalents; therefore, each
shall conform to the requirements of Specification A957/
system shall be used independently of the other. Combining
A957M, including any supplementary requirements that are
values from the two systems may result in nonconformance
indicated in the purchase order. Failure to comply with the
with the standard.
common requirements of Specification A957/A957M consti-
tutes nonconformance with this specification. In case of con-
1.4 This standard does not purport to address all of the
flict between the requirements of this specification and Speci-
safety concerns, if any, associated with its use. It is the
fication A957/A957M, Specification A957/A957M shall
responsibility of the user of this standard to establish appro-
prevail.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
4. Ordering Information
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
4.1 Orders for material under this specification should
include the following information in proper sequence.
4.1.1 Quantity,
This specification is under the jurisdiction of ASTM Committee A01 on Steel,
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee
A01.18 on Castings. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2020. Published May 2020. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1901. Last previous edition approved in 2019 as A27/A27M – 19. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/A0027_A0027M-20. the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A27/A27M−20
4.1.2 Specification, grade (1.2), and class (9.2), 7. Tensile Properties
4.1.3 Description of the casting by pattern number or
7.1 Except for Grades N-1 and N-2, one tension test shall be
drawing,
performed on each heat and the mechanical properties shall
4.1.4 Options in the specification, and
conform to the requirements specified in Table 2.
4.1.5 Supplementary requirements desired, including stan-
7.2 Test coupons may be cut from the heat-treated (if
dards of acceptance.
required) castings at the producer’s option.
5. Heat Treatment
8. Retests
5.1 All castings of Grades N-2, 60-30 [415-205], 65-35
8.1 If any specimen is machined improperly or if flaws are
[450-240], 70-36 [485-250], and 70-40 [485-275] shall be heat
revealed by machining or during testing, the specimen may be
treated by annealing, normalizing, normalizing and tempering,
discarded and another substituted from the same heat.
or quenching and tempering. Unless otherwise specified in the
8.2 At the manufacturer’s option, castings may be reheat
inquiry, contract, or order, the castings may be heat treated by
treatedandretested.Whencastingsarereheattreated,theymay
any one or combination of these heat treatments at the option
not be re-austenitized more than three times without the
of the manufacturer.
approval of the purchaser. Testing after reheat treatment shall
5.1.1 Heat treatment shall be performed after castings have
consist of the full number of specimens taken from locations
been allowed to cool from the pouring temperature to below
complying with the specification or order.
the transformation range.
9. Rework and Retreatment
5.2 Furnace temperatures for heat treating shall be regulated
by the use of pyrometers. 9.1 All welds shall be inspected to the same quality stan-
dards as were used to inspect the casting.
6. Chemical Composition
9.2 If post-weld heat treatment is required, Class 1 must be
6.1 The steel shall conform to the requirements as to
specified along with the grade, and the welds to be heat treated
chemical composition prescribed in Table 1. Product analysis
must be defined. If post-weld heat treatment is not required,
tolerances shall conform to the Product Analysis Tolerances
Class 2 must be specified along with the grade.
shown in Specification A781/A781M or Specification A957/
10. Keywords
A957M. When residual element chemical content is of interest
to the purchaser, S54 m
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: A27/A27M − 19 A27/A27M − 20
Standard Specification for
Steel Castings, Carbon, for General Application
This standard is issued under the fixed designation A27/A27M; 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*
1.1 This specification covers carbon steel castings for general applications that require up to 70 ksi (485 MPa) minimum tensile
strength.
NOTE 1—The grades covered by this specification represent materials that are suitable for assembly with other steel castings or wrought steel parts by
fusion welding. It is not intended to imply that all these grades possess the same degree of weldability or that the same welding techniques can be used
on all castings. It is the responsibility of the purchaser to establish for himself a suitable welding technique.
1.2 Several grades and two classes of steel castings are covered, as indicated below. The grade and class desired shall be
specified by the purchaser.
1.2.1 Grade N-1—Chemical analysis only.
1.2.2 Grade N-2—Heat treated but not mechanically tested.
1.2.3 Grade U-60-30 [415-205]—Mechanically tested but not heat treated.
1.2.4 Grades 60-30 [415-205], 65-35 [450-240], 70-36 [485-250], and 70-40 [485-275]—Heat treated and mechanically tested.
1.2.5 Class 1 and Class 2 steel castings shall be specified in accordance with 9.2.
1.3 The 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 nonconformance with the standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A781/A781M Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use
A957/A957M Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use
3. General Conditions for Delivery
3.1 Except for steel investment castings, material furnished to this specification shall conform to the requirements of
Specification A781/A781M, including any supplementary requirements that are indicated in the purchase order. Failure to comply
with the general requirements of Specification A781/A781M constitutes nonconformance with the specification. In case of a
conflict between the requirements of this specification and Specification A781/A781M, this specification shall prevail.
3.2 Steel investment castings furnished to this specification shall conform to the requirements of Specification A957/A957M,
including any supplementary requirements that are indicated in the purchase order. Failure to comply with the common
This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.18
on Castings.
Current edition approved Sept. 1, 2019May 1, 2020. Published September 2019May 2020. Originally approved in 1901. Last previous edition approved in 20172019 as
A27/A27M – 17.A27/A27M – 19. DOI: 10.1520/A0027_A0027M-19.10.1520/A0027_A0027M-20.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A27/A27M − 20
requirements of Specification A957/A957M constitutes nonconformance with this specification. In case of conflict between the
requirements of this specification and Specification A957/A957M, Specification A957/A957M shall prevail.
4. Ordering Information
4.1 Orders for material under this specification should include the following information in proper sequence.
4.1.1 Quantity,
4.1.2 Specification, grade (1.2), and class (9.2),
4.1.3 Description of the casting by pattern number or drawing,
4.1.4 Options in the specification, and
4.1.5 Supplementary requirements desired, including standards of acceptance.
5. Heat Treatment
5.1 All castings of Grades N-2, 60-30 [415-205], 65-35 [450-240], 70-36 [485-250], and 70-40 [485-275] shall be heat treated
by annealing, normalizing, normalizing and tempering, or quenching and tempering. Unless otherwise specified in the inquiry,
contract, or order, the castings may be heat treated by any one or combination of these heat treatments at the option of the
manufacturer.
5.1.1 Heat treatment shall be performed after castings have been allowed to cool from the pouring temperature to below the
transformation range.
5.2 Furnace temperatures for heat treating shall be regulated by the use of pyrometers.
6. Chemical Composition
6.1 The steel shall conform to the requirements as to chemical composition prescribed in Table 1. Product analysis tolerances
shall conform to the Product Analysis Tolerances shown in Specification A781/A781M or Specification A957/A957M. When
residual element chemical content is of interest to the purchaser, S54 may be considered.
7. Tensile Properties
7.1 Except for Grades N-1 and N-2, one tension test shall be performed on each heat and the mechanical properties shall
conform to the requirements specified in Table 2.
7.2 Test coupons may be cut from the heat-treated (if required) castings at the producer’s option.
8. Retests
8.1 If any specimen is machined improperly or if flaws are revealed by machining or during testing, the specimen may be
discarded and another substituted from the same heat.
TABLE 1 Chemical Requirements
Composition, %
A
Grade (UNS No.)
B B
Carbon, max Manganese, max Silicon, max Sulfur, max Phosphorus, max
Grade N-1 (J02500) 0.25 0.75 0.80 0.035 0.035
Grade N-2 (J03500) 0.35 0.60 0.80 0.035 0.035
Grade U-60-30 [415-205] (J02500) 0.25 0.75 0.80 0.035 0.035
Grade 60-30 [415-205] (J03000) 0.30 0.60 0.80 0.035 0.035
Grade 65-35 [450-240] (J03001) 0.30 0.70 0.80 0.035 0.035
Grade 70-36 [485-250] (J03501) 0.35 0.70 0.80 0.035 0.035
Grade 70-40 [485-275] (J02501) 0.25 1.20 0.80 0.035 0.035
A
TABLE 1 Chemical Composition Requirements
Element, %
B
Grade (UNS Number)
C C
Carbon Manganese Phosphorus Sulfur Silicon
N-1 (J02500) 0.25 0.75 0.035 0.035 0.80
N-2 (J03500) 0.35 0.60 0.035 0.035 0.80
U-60-30 [415-205] (J02500) 0.25 0.75 0.035 0.035 0.80
60-30 [415-205] (J03000) 0.30 0.60 0.035 0.035 0.80
65-35 [450-240] (J03001) 0.30 0.70 0.035 0.035 0.80
70-36 [485-250] (J03501) 0.35 0.70 0.035 0.035 0.80
70-40 [485-275] (J02501) 0.25 1.20 0.035 0.035 0.80
A
All values are maximums.
B
Specify Class 1 or Class 2 in addition to grade designation (see 9.2).
C
For each reduction of 0.01 % carbon below the maximum specified, an increase o
...