ASTM A732/A732M-20

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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: A732/A732M − 14 A732/A732M − 20
Standard Specification for
Castings, Investment, Carbon and Low Alloy Low-Alloy
Steel for General Application, and Cobalt Alloy for High
Strength at Elevated Temperatures
This standard is issued under the fixed designation A732/A732M; 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.
1. Scope*
1.1 This specification covers carbon and low-alloy steel and cobalt alloy castings made by the investment casting process.
1.2 Fifteen grades of steel and two cobalt alloy grades are covered.
1.3 Supplementary requirements of an optional nature are provided for use at the option of the purchaser. The supplementary
requirements shall apply only when specified individually by the purchaser in the purchase order or contract.
1.4 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 non-conformancenonconformance with the standard.
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:
A941 Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
A957/A957M Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use
A997 Practice for Investment Castings, Surface Acceptance Standards, Visual Examination
E21 Test Methods for Elevated Temperature Tension Tests of Metallic Materials
E139 Test Methods for Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials
3. Ordering Information
3.1 Orders for castings under this specification should include the following information:
3.1.1 Quantity,
3.1.2 ASTM designation and issue date,
3.1.3 Grade designation (Tables 1 and 2), and
3.1.4 Description of casting by part, pattern, or drawing number. (Dimensional tolerances and machined surfaces shall be
indicated on the casting drawing.).drawing.)
3.2 The purchaser should specify any of the following information to describe adequately describe the desired material:
3.2.1 Heat-treat condition (see 5.1 and 5.2),
3.2.2 Repair welding (see Section 8 and Specification A957/A957M),
3.2.3 Source inspection, if any (see Specification A957/A957M), and
3.2.4 Supplementary requirements required (marking, certification, mechanical properties, NDT, and the like).
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 March 1, 2014May 1, 2020. Published March 2014May 2020. Originally approved in 1976. Last previous edition approved in 20092014 as
A732/A732M – 09.A732/A732M – 14. DOI: 10.1520/A0732_A0732M-14.10.1520/A0732_A0732M-20.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. 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
A732/A732M − 20
TABLE 1 Chemical Requirements
Grade 1A 2A,2Q2A, 2Q 3A,3Q 3A, 3Q 4A,4Q4A, 4Q 5N 6N 7Q 8Q
Medium Medium Medium Manganese Chromium Chromium
Low Carbon Vanadium
Type Carbon Carbon Carbon Molybdenum Molybdenum Molybdenum
A
IC 1020 IC 6120
IC 1030 IC 1040 IC 1050 IC 4020 IC 4130 IC 4140
Carbon 0.15 to 0.25 0.25 to 0.35 0.35 to 0.45 0.45 to 0.55 0.30 max 0.35 max 0.25 to 0.35 0.35 to 0.45
Manganese 0.20 to 0.60 0.70 to 1.00 0.70 to 1.00 0.70 to 1.00 0.70 to 1.00 1.35 to 1.75 0.40 to 0.70 0.70 to 1.00
Phosphorus, max 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04
Sulfur, max 0.045 0.045 0.045 0.045 0.045 0.045 0.045 0.045
Silicon 0.20 to 1.00 0.20 to 1.00 0.20 to 1.00 0.20 to 1.00 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80
Nickel
Chromium 0.80 to 1.10 0.80 to 1.10
Molybdenum 0.25 to 0.55 0.15 to 0.25 0.15 to 0.25
Vanadium 0.05 to 0.15
Residual Elements:
Copper 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50
Nickel 0.50 0.50 0.50 0.50 0.50 0.50
Chromium 0.35 0.35 0.35 0.35 0.35
Molybdenum + Tungsten 0.25 0.25
Tungsten 0.10 0.10 0.10 0.25 0.10 0.10
Total content of these 1.00 1.00 1.00 0.60 1.00 1.00 0.60 1.00
residual elements
Grade 9Q 10Q 11Q 12Q 13Q 14Q 15A
Chrome Nickel Chrome Nickel Nickel Molyb- Chromium Chrome Nickel Chrome Nickel
Chromium
Type Molybdenum Molybdenum denum Vanadium Molybdenum Molybdenum
IC 52100
IC 4330 IC 4340 IC 4620 IC 6150 IC 8620 IC 8630
Carbon 0.25 to 0.35 0.35 to 0.45 0.15 to 0.25 0.45 to 0.55 0.15 to 0.25 0.25 to 0.35 0.95 to 1.10
Manganese 0.40 to 0.70 0.70 to 1.00 0.40 to 0.70 0.65 to 0.95 0.65 to 0.95 0.65 to 0.95 0.25 to 0.55
Phosphorus, max 0.04 0.04 0.04 0.04 0.04 0.04 0.04
Sulfur, max 0.045 0.045 0.045 0.045 0.045 0.045 0.045
Silicon 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80 0.20 to 0.80
Nickel 1.65 to 2.00 1.65 to 2.00 1.65 to 2.00 0.40 to 0.70 0.40 to 0.70
Chromium 0.70 to 0.90 0.70 to 0.90 0.80 to 1.10 0.40 to 0.70 0.40 to 0.70 1.30 to 1.60
Molybdenum 0.20 to 0.30 0.20 to 0.30 0.20 to 0.30 0.15 to 0.25 0.15 to 0.25
Vanadium 0.15 min
Residual Elements:
Copper 0.50 0.50 0.50 0.50 0.50 0.50 0.50
Nickel 0.50 0.50
Chromium 0.35
Molybdenum + Tungsten 0.10
Tungsten 0.10 0.10 0.10 0.10 0.10 0.10
Total content of these 0.60 1.00 1.00 1.00 1.00 1.00 0.60
residual elements
A
Investment Casting (IC) numbers are to be used only for nomenclature comparison.
A
Investment Casting (IC) numbers are to be used only for nomenclature comparison.
TABLE 2 Chemical Requirements-CobaltRequirements—Cobalt
Alloys
Grade 21 31
Carbon 0.20–0.30 0.45–0.55
Manganese, max. 1.00 1.00
Manganese, max 1.00 1.00
Silicon, max 1.00 1.00
Phosphorus, max 0.040 0.040
Sulfur, max 0.040 0.040
Chromium 25.0–29.0 24.5–26.5
Nickel 1.7–3.8 9.5–11.5
Cobalt remainder remainder
Molybdenum 5.0–6.0 .
Molybdenum 5.0–6.0 . . .
Tungsten . 7.0–8.0
Tungsten . . . 7.0–8.0
Iron, max. 3.00 2.00
Iron, max 3.00 2.00
Boron 0.007 max 0.005–0.015
4. General Requirements
4.1 Material furnished to this specification shall conform to the requirements of Specification A957/A957M, including any
supplementary requirements that are indicated on the purchase order. Failure to comply with the requirements of Specification
A732/A732M − 20
A957/A957M constitutes nonconformance with this specification. In case of conflict of this specification and Specification
A957/A957M, this specification shall prevail.
5. Heat Treatment
5.1 Steel castings shall be heat treated either by full annealing, normalizing, normalizing and tempering, or quenching and
tempering to obtain the specified properties or other properties that have been agreed upon within each grade. In this latter instance,
Supplementary Requirement S53 shall be used.
5.1.1 Heat treatment shall be performed after the castings have been allowed to cool below the transformation range.
5.2 Cobalt alloy castings shall be supplied in the as-cast condition unless otherwise agreed upon by supplier and purchaser.
5.3 Definitions of terms relating to heat treatment shall be in accordance with Terminology A941.
6. Chemical Composition
6.1 The castings shall conform to the requirements for chemical composition specified in Table 1Tables 1 and 2 and Table 2.
7. Quality
7.1 The surface of the casting shall be examined visually to meet the requirements of Practice A997. Acceptance criteria to be
mutually agreed upon between supplier and purchaser.
7.2 The castings shall not be peened or plugged or impregnated.
8. Repair by Welding
8.1 Welding shall be accomplished with a filler metal that produces a weld deposit with a chemical composition similar to the
casting. Castings ordered in the annealed condition or for subsequent hardening shall be annealed after weld repairs. Castings
ordered heat treated shall be post weld post-weld heat treated in accordance with the qualified welding procedure after weld repairs,
with the exception of Grades 1A and 2A, where post weld post-weld heat treatment is optional.
8.2 Welds shall be subject to the same quality standards as used to inspect the castings.
9. Keywords
9.1 alloy steel; carbon steel; cobalt alloys; investment castings; steel castings
SUPPLEMENTARY REQUIREMENTS
The following supplementary requirements shall not apply unless specified in the purchase order. A
list of standardized supplementary requirements for use at the option of the purchaser is included in
Specification A957/A957M. Those ordinarily considered suitable for use with this specification are
given below, together with additional supplementary requirements that are applicable only to this
specification. Other supplementary requirements enumerated in Specification A957/A957M may be
used with this specification upon agreement between supplier and purchaser.
A732/A732M − 20
S1. Magnetic Particle Inspection
S2. Radiographic Inspection
S3. Liquid Penetrant Inspection
S6. Certification
S7. Prior Approval of Major Weld Repairs
S8. Marking
S10. Hardness Test
S13. Unspecified Elements
S16. Weld Repair Charts
S18. Hot Isostatic Pressing (HIPing)
S22. Decarburization
S53. Mechanical Properties
S53.1 Mechanical properties other than those specified in Table S54.1 may be ordered for each of the grades. The properties
shall be agreed upon between the supplier and the purchaser.
TABLE S54.1 Tensile Requirements
Tensile strength, min Yield strength, min Elongation, in 2-in.
[50-mm]2 in. Heat
Grade
[50 mm] or 4 Treatment
ksi [MPa] ksi [MPa]
diameters
A
1A 60 [414] 40 [276] 24 A
2A 65 [448] 45 [310] 25 A
B
2Q 85 [586] 60 [414] 10 Q T
3A 75 [517] 48 [331] 25 A
3Q 100 [689] 90 [621] 10 Q T
4A 90 [621] 50 [345] 20 A
4Q 125 [862] 100 [689] 5 Q T
C
5N 85 [586] 55 [379] 22 N T
6N 90 [621]
...