ASTM A494/A494M-22

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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: A494/A494M − 18a A494/A494M − 22
Standard Specification for
Castings, Nickel and Nickel Alloy
This standard is issued under the fixed designation A494/A494M; 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 nickel, nickel-copper, nickel-copper-silicon, nickel-molybdenum, nickel-chromium, and nickel-
molybdenum-chromium alloy castings for corrosion-resistant service.
1.2 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.
1.3 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:
A370 Test Methods and Definitions for Mechanical Testing of Steel Products
A488/A488M Practice for Steel Castings, Welding, Qualifications of Procedures and Personnel
A732/A732M Specification for Castings, Investment, Carbon and Low-Alloy Steel for General Application, and Cobalt Alloy
for High Strength at Elevated Temperatures
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
E8/E8M Test Methods for Tension Testing of Metallic Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E30 Test Methods for Chemical Analysis of Steel, Cast Iron, Open-Hearth Iron, and Wrought Iron (Withdrawn 1995)
E38 Methods for Chemical Analysis of Nickel-Chromium and Nickel-Chromium-Iron Alloys (Withdrawn 1989)
E76 Test Methods for Chemical Analysis of Nickel-Copper Alloys (Withdrawn 2003)
E354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and Other Similar Iron, Nickel, and
Cobalt Alloys
3. Terminology
3.1 Definitions:
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 Nov. 1, 2018March 1, 2022. Published November 2018March 2022. Originally approved in 1963. Last previous edition approved in 2018 as
A494/A494M – 18.A494/A494M – 18a. DOI: 10.1520/A0494_A0494M-18A.10.1520/A0494_A0494M-22.
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.
The last approved version of this historical standard is referenced on www.astm.org.
*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
A494/A494M − 22
3.1.1 master heat—a single furnace charge of refined alloy, which may either be poured directly into castings or into remelt alloy
for individual melts.
3.1.2 melts—a single furnace charge poured into castings. When master heats are used to prepare melts, a melt analysis shall be
reported.
4. General Conditions for Delivery
4.1 Except for investment castings, castings furnished to this specification shall conform to the requirements of Specification
A781/A781M, including any supplementary requirements that are indicated on the purchase order. Failure to comply with the
general requirements of Specification A781/A781M constitutes nonconformance with this specification. In case of conflict between
the requirements of this specification and Specification A781/A781M, this specification shall prevail.
4.2 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 general 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.
5. Ordering Information
5.1 Orders for castings to this specification should include the following information:
5.1.1 Quantity, in pieces, and
5.1.2 Grade designation (Table 1) and class (Table 2).
5.2 The purchaser shall specify any of the following information required to adequately describe the desired material:
5.2.1 Heat-treat condition (see 6.1 and 6.2),
5.2.2 Repair welding (see Section 11),
5.2.3 Source inspection requirements, if any (see Specification A781/A781M),
5.2.4 Marking-for-identification requirements, if any (see 13.1), and
5.2.5 Supplementary requirements desired, including the standards of acceptance.
6. Heat Treatment
6.1 Castings shall be heat treated in accordance with the requirements in Table 2.
NOTE 1—Proper heat treatment of these alloys is usually necessary to enhance corrosion resistance and, in some cases, to meet mechanical properties.
Minimum heat-treat temperatures are specified; however, it is sometimes necessary to heat treat at higher temperatures, hold for some minimum time at
temperature, and then rapidly cool the castings in order to enhance the corrosion resistance and meet mechanical properties.
6.2 When Class 1 is specified, grades CY40 and M25S shall be supplied in the as-cast condition. When Class 2 is specified, grades
CY40 and M25S shall be supplied in the solution heat-treated condition. When Class 3 is specified, grade M25S shall be supplied
in the age-hardened condition.
7. Chemical Composition
7.1 These alloys shall conform to the chemical composition requirements prescribed in Table 1.
7.2 The grades that pertain to this specification are placed into the five general categories given below. The producer shall report
for information all elements in Table 1 for which a limit is given for any alloy in the same alloy family. The alloy families are:
A494/A494M − 22
A,B
TABLE 1 Composition Requirements
Grade Element, %
C
Type Carbon Manganese Phosphorus Sulfur Silicon Copper Molybdenum Iron Nickel Chromium Niobium Tungsten Vanadium Bismuth Tin
UNS
Material
Grade,
Type,
Element,
UNS
%
C C
CZ100 M25S M30H M35-2 N3M N7M N12MV
M30C M35-1
Ni Ni-Cu Ni-Cu Ni-Cu Ni-Cu Ni-Cu Ni-Mo Ni-Mo Ni-Mo
N24130 N24135
N02100 N24025 N24030 N04020 N30003 N30007 N30012
Carbon 1.00 0.25 0.30 0.30 0.35 0.35 0.03 0.07 0.12
Manganese 1.50 1.50 1.50 1.50 1.50 1.50 1.00 1.00 1.00
Phosphorus 0.03 0.03 0.03 0.03 0.03 0.03 0.030 0.030 0.030
Sulfur 0.02 0.02 0.02 0.02 0.02 0.02 0.020 0.020 0.020
E E
CU5MCuC 0.050 1.0 0.030 0.020 1.0 1.50–3.50 2.5–3.5 Balance 38.00–44.0 19.5–23.5 0.60–1.20 . . . . . .
Ni-Cr
N08826
Silicon 2.00 3.5 – 4.5 1.0 – 2.0 2.7 – 3.7 1.25 2.00 0.50 1.00 1.00
Copper 1.25 27.0 – 26.0 – 27.0 – 26.0 – 26.0 – . . . . . . . . .
33.0 33.0 33.0 33.0 33.0
E E E
CW2M 0.02 1.00 0.03 0.02 0.80 15.0–17.5 2.0 Balance 15.0–17.5 1.0 . . . . . .
Ni-Cr
N26455
E E E E
CW6M 0.07 1.00 0.030 0.020 1.00 17.0–20.0 3.0 Balance 17.0–20.0 . . . . . .
Ni-Cr
N30107
Molybdenum . . . . . . . . . . . . . . . . . . 30.0 – 30.0 – 26.0 –
33.0 33.0 30.0
E E E
CW6MC 0.06 1.00 0.015 0.015 1.00 8.0–10.0 5.0 Balance 20.0–23.0 3.15–4.50 . . . . . .
Ni-Cr
N26625
Iron 3.00 3.50 3.50 3.50 3.50 3.50 3.00 3.00 4.0 – 6.0
Nickel 95.00 Balance Balance Balance Balance Balance Balance Balance Balance
(min)
E E
CW12MW 0.12 1.00 0.030 0.020 1.00 16.0–18.0 4.5–7.5 Balance 15.5–17.5 3.75–5.25 0.20–0.40 . . . . . .
Ni-Cr
N30002
Chromium . . . . . . . . . . . . . . . . . . 1.0 1.0 1.00
E E E E
CX2M 0.02 1.00 0.020 0.020 0.50 15.0–16.5 1.50 Balance 22.0–24.0 . . . . . .
Ni-Cr
N26059
E E
Columbium . . . 1.0 – 3.0 0.5 0.5 . . . . . .
. . .
D
(Niobium)
E E
CX2MW 0.02 1.00 0.025 0.020 0.80 12.5–14.5 2.0–6.0 Balance 20.0–22.5 2.5–3.5 0.35 . . . . . .
Ni-Cr
N26022
Tungsten . . . . . . . . . . . . . . . . . . . . . . . . . . .
E E
Vanadium . . . . . . . . . . . . . . . . . . 0.20 –
0.60
A494/A494M − 22
TABLE 1 Continued
Grade Element, %
C
Type Carbon Manganese Phosphorus Sulfur Silicon Copper Molybdenum Iron Nickel Chromium Niobium Tungsten Vanadium Bismuth Tin
UNS
E E E E E
CY40 0.40 1.50 0.03 0.02 3.00 11.0 Balance 14.0–17.0 . . . . . .
Ni-Cr
N06040
Bismuth . . . . . . . . . . . . . . . . . . . . . . . . . . .
CY5SnBiM 0.05 1.5 0.03 0.02 0.5 . . . 2.0–3.5 2.0 Balance 11.0–14.0 . . . . . . . . . 3.0–5.0 3.0–5.0
Other
N26055
Tin . . . . . . . . . . . . . . . . . . . . . . . . . . .
CZ100 1.00 1.50 0.03 0.02 2.00 1.25 . . . 3.00 95.00 . . . . . . . . . . . . . . . . . .
Ni min
N02100
Material
Grade,
Type,
Element,
UNS
%
CU5MCuC CW2M CW6M CW6MC CW12MW CX2M CX2MW CY40 CY5SNBiM
Ni-Cr Ni-Cr Ni-Cr Ni-Cr Ni-Cr Ni-Cr Ni-Cr Ni-Cr Other
N08826 N26455 N30107 N26625 N30002 N26059 N26022 N06040 N26055
Carbon 0.050 0.02 0.07 0.06 0.12 0.02 0.02 0.40 0.05
Manganese 1.0 1.00 1.00 1.00 1.00 1.00 1.00 1.50 1.5
Phosphorus 0.030 0.03 0.030 0.015 0.030 0.020 0.025 0.03 0.03
Sulfur 0.020 0.02 0.020 0.015 0.020 0.020 0.020 0.02 0.02
Silicon 1.0 0.80 1.00 1.00 1.00 0.50 0.80 3.00 0.5
E E E E E E E
Copper 1.50 – . . .
3.50
E
M25S 0.25 1.50 0.03 0.02 3.5–4.5 27.0–33.0 . . . 3.50 Balance . . . . . . . . . . . . . . .
Ni-Cu
N24025
E
Molybdenum 2.5 – 3.5 15.0 – 17.0 – 8.0 – 16.0 – 15.0 – 12.5 – 2.0 – 3.5
17.5 20.0 10.0 18.0 16.5 14.5
Iron Balance 2.0 3.0 5.0 4.5 – 7.5 1.50 2.0 – 6.0 11.0 2.0
D
M30C 0.30 1.50 0.03 0.02 1.0–2.0 26.0–33.0 . . . 3.50 Balance . . . 1.0–3.0 . . . . . . . . . . . .
Ni-Cu
N24130
Nickel 38.00 – Balance Balance Balance Balance Balance Balance Balance Balance
44.0
Chromium 19.5 – 15.0 – 17.0 – 20.0 – 15.5 – 22.0 – 20.0 – 14.0 – 11.0 –
23.5 17.5 20.0 23.0 17.5 24.0 22.5 17.0 14.0
E E E E E E
Columbium 0.60 – 3.15 – . . .
D
(Niobium) 1.20 4.50
E
M30H 0.30 1.50 0.03 0.02 2.7–3.7 27.0–33.0 . . . 3.50 Balance . . . . . . . . . . . . . . .
Ni-Cu
N24030
E E E E E
Tungsten 1.0 3.75 – 2.5 – 3.5 . . .
5.25
D
M35-1 0.35 1.50 0.03 0.02 1.25 26.0–33.0 . . . 3.50 Balance . . . 0.5 . . . . . . . . . . . .
Ni-Cu
N24135
A494/A494M − 22
TABLE 1 Continued
Grade Element, %
C
Type Carbon Manganese Phosphorus Sulfur Silicon Copper Molybdenum Iron Nickel Chromium Niobium Tungsten Vanadium Bismuth Tin
UNS
E E E E E E
Vanadium 0.20 – 0.35 . . .
0.40
Bismuth . . . . . . . . . . . . . . . . . . . . . . . . 3.0 – 5.0
M35-2 0.35 1.50 0.03 0.02 2.00 26.0–33.0 . . . 3.50 Balance . . . 0.5 . . . . . . . . . . . .
Ni-Cu
N04020
E
N3M 0.03 1.00 0.030 0.020 0.50 . . . 30.0–33.0 3.00 Balance 1.0 . . . . . . . . . . . .
Ni-Mo
N30003
Tin . . . . . . . . . . . . . . . . . . . . . . . . 3.0 – 5.0
E
N7M 0.07 1.00 0.030 0.020 1.00 . . . 30.0–33.0 3.00 Balance 1.0 . . . . . . . . . . . .
Ni-Mo
N30007
N12MV 0.12 1.00 0.030 0.020 1.00 . . . 26.0–30.0 4.0–6.0 Balance 1.00 . . . . . . 0.20–0.60 . . . . . .
Ni-Mo
N30012
A
Where ellipses (.) appear in this table, there is no requirement, and the element need not be analyzed for or reported.
B
All values are maximum unless a specified as a minimum or a range is provided.
C
Order M35-1 or M30C when weldability is required.
C
Columbium (Cb) and niobium (Nb) are interchangeable names for the same element 41.
D
Order M35-1 or M30C when weldability is required.
E
Element to be analyzed and reported for information only. See paragraph 5.5 (Grade Substitution) of Specification A781/A781M or for investment castings, Specification A957/A957M.

A494/A494M − 22
TABLE 2 Heat-Treat Requirements
Grade Heat Treatment
CZ100, M35-1, M35-2, CY40 Class 1, M30H, M30C, As cast
M25S Class 1, CY5SnBiM
A
M25S, Class 2 Load into furnace at 600 °F [315 °C] maximum. Heat to 1600 °F [870 °C] and
hold for 1 h plus an additional 30 min for each ⁄2 in. [13 mm] of cross section
B C
over 1 in. Cool to 1300 °F [705 °C] and hold at temperature for 30 min then
quench in oil to room temperature.
M25S, Class 3 Load into furnace at 600 °F [315 °C] maximum. Heat slowly to 1100 °F [605 °C]
and hold to develop maximum hardness. Furnace or air cool to room
temperature.
N12MV, N7M, N3M Heat to 2000 °F [1095 °C] minimum, hold for sufficient time to heat castings to
temperature, quench in water or rapid cool by other means.
CW12MW, CW6M, CW6MC, CW2M Heat to 2150 °F [1175 °C] minimum, hold for sufficient time to heat castings to
temperature, quench in water or rapid cool by other means.
CY40, Class 2 Heat to 1900 °F [1040 °C] minimum, hold for sufficient time to heat castings to
temperature, quench in water or rapid cool by other means.
CX2MW Heat to 2200 °F [1205 °C] minimum, hold for sufficient time to heat castings to
temperature, quench in water or rapid air cool by other means.
CU5MCuC Heat to 2100 °F [1150 °C] minimum, hold for sufficient time to heat castings to
temperature, quench in water. Stabilize at 1725 – 1815 °F [940 – 990 °C], hold
for sufficient time to heat castings to temperature, quench in water or rapid cool
by other means.
CU5MCuC Heat to 2100 °F [1150 °C] minimum, hold for sufficient time to heat castings to
temperature, quench in water. Stabilize at 1725–1815 °F [940–990 °C], hold for
sufficient time to heat castings to temperature, quench in water or rapid cool by
other means.
CX2M Heat to 2100 °F [1150 °C] minimum, hold for sufficient time to heat castings to
temperature, quench in water or rapid air cool by other means.
A
M25S, while machinable in the “as-cast” condition, is capable of being solution heat treated for improved machinability. It may be subsequently age hardened to the
hardness specified in Table 3 and finished machined or ground.
B
For cross sections over 6 in. [125 mm], it may be necessary to increase the hold time if maximum softness is desired.
C
For maximum softness and the least variation in hardness levels, castings should be transferred from an oven at 1600 °F [870 °C] to a second oven at 1300 °F [705 °C].
(1) Nickel – CZ100
(2) Nickel-copper – M35-1, M35-2, M30C, M30H, M25S
(3) Nickel-molybdenum – N12MV, N7M, N3M
(4) Nickel-chromium – CY40, CW6M, CW2M, CW6MC, CX2MW, CU5MCuC, CX2M
(5) Other – CY5SnBiM
7.3 An analysis of each master heat shall be made by the manufacturer to determine the percentages of the elements specified in
Table 1. The analysis shall be made from a representative sample taken during the pouring of the master heat. Chemical
composition shall be reported to the purchaser or their representative.
7.4 Test Methods E76 or E354 shall be used for referee purposes. Test Methods E30 or E38 shall be used if Test Methods E76
or E354 do not include a method for some element present in the material.
8. Tensile Properties
8.1 One tension test shall be made from each master heat except for grades M25S and CY5SnBiM when the master heat is used
to
...