ASTM A436-84(2006)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: A436 – 84 (Reapproved 2006)
Standard Specification for
Austenitic Gray Iron Castings
This standard is issued under the fixed designation A436; 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 Department of Defense.
1. Scope 3.1.2 Type of austenitic gray iron required (see 5.1),
3.1.3 Heat treatment required (see 4.2 through 4.5),
1.1 This specification covers austenitic gray iron castings
3.1.4 If repair of castings is permitted (see 4.6),
that are used primarily for their resistance to heat, corrosion,
3.1.5 Size and number of test bars required (see 11 through
and wear. Austenitic gray iron is characterized by uniformly
8.4 and 12.1),
distributed graphite flakes, some carbides, and the presence of
3.1.6 If special tests are required (see Section 7 and 9.1),
sufficient alloy content to produce an austenitic structure.
3.1.7 If certification is required (see 14.1), and
1.2 The values stated in inch-pound units are to be regarded
3.1.8 If different preparation for delivery requirements are
as the standard.
needed (see 15.1).
2. Referenced Documents
4. Materials and Manufacture
2.1 ASTM Standards:
4.1 Melting may be done in any furnace that produces
E30 Test Methods for Chemical Analysis of Steel, Cast
castings meeting the chemical compositions and mechanical
Iron, Open-Hearth Iron, and Wrought Iron
properties outlined in this specification. These include cupolas,
E59 Practice for Sampling Steel and Iron for Determination
air furnaces, electric furnaces, crucible furnaces, and so forth.
of Chemical Composition
4.2 By agreement between the manufacturer and the pur-
E94 Guide for Radiographic Examination
chaser, the castings may be stress relieved by heating to and
E165 PracticeforLiquidPenetrantExaminationforGeneral
holding in the temperature range from 1150 to 1200°F (620 to
Industry
650°C) for not less than 1 nor more than 2 h/in. of thickness in
E351 Test Methods for Chemical Analysis of Cast Iron—
the thickest section. Heating and cooling shall be uniform and
All Types
shall be not more than 400°F (222°C)/h for castings less than
E433 Reference Photographs for Liquid Penetrant Inspec-
1 in. in maximum thickness, nor more than 400°F/h divided by
tion
the maximum section thickness in inches for thicker castings.
E446 Reference Radiographs for Steel Castings Up to 2 in.
During the cooling cycle, castings may be cooled in still air
[51 mm] in Thickness
after the temperature has dropped to 600°F (315°C).
3. Ordering Information 4.3 If the manufacturer can demonstrate that another treat-
ment provides satisfactory stress relief, it may be used by
3.1 Orders for material to this specification shall include the
agreement between the manufacturer and the purchaser.
following information:
4.4 Whenever dimensional changes in high-temperature
3.1.1 ASTM designation and date of issue,
service are a problem, by agreement between the manufacturer
and the purchaser, the castings may be stabilized by heating at
This specification is under the jurisdiction of ASTM Committee A04 on Iron
1600°F (870°C) for 1 h/in. of section, for a minimum of 1 h.
CastingsandisthedirectresponsibilityofSubcommitteeA04.01onGreyandWhite
Otherwise, the austenite that is supersaturated with respect to
Iron Castings.
carbon may reject carbon during service and produce dimen-
Current edition approved Oct. 1, 2006. Published October 2006. Originally
approved in 1959. Last previous edition approved in 2001 asA436–84 (2001). DOI:
sional changes.
10.1520/A0436-84R06.
4.5 By agreement between the manufacturer and the pur-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
chaser, castings with chilled edges or excessive carbides may
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 be annealed at 1750 to 1900°F (955 to 1040°C) for ⁄2 to5h,
the ASTM website.
followed by uniform cooling, preferably in still air.
Withdrawn
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
A436 – 84 (2006)
4.6 Castings shall not be repaired by welding, plugging, or used. It shall be an open mold made of suitable core sand with
other methods without written permission from the purchaser. aminimumof1 ⁄2 in.(38mm)ofsandonallsidesandbottom.
8.3 It is recommended that test bars be poured immediately
5. Chemical Composition
after the castings and from the same ladle of metal. If castings
5.1 Many combinations of alloys can be used to obtain an
are to be heat treated, test bars shall be included in the same
austenitic gray iron. This specification includes only the six
furnace load.
types defined by the chemical composition limits specified in
8.4 By agreement between the manufacturer and the pur-
Table 1.
chaser, tension test specimens may be cut directly from
5.2 The chemical analysis for total carbon shall be made on
centrifugal or other permanent mold castings. The location and
chilled cast pencil-type specimens or from thin wafers approxi-
orientation of such tension test specimens cut from castings
mately ⁄32 in. (0.8 mm) thick cut from test coupons. Drillings
shall be specified as agreed upon by the manufacturer and the
are not reliable because of the probable loss of graphite.
purchaser.
5.3 Drillings taken from test coupons, broken test speci-
9. Workmanship, Finish, and Appearance
mens, or castings shall conform to the requirements for
chemical composition as given in Table 1. Sampling shall be
9.1 The castings shall conform substantially to the dimen-
conducted in accordance with Practice E59 and chemical
sions on the drawings furnished by the purchaser, or if no
analysis in accordance with Test Methods E351 and Test
drawing has been provided, to the dimensions predicated by
Methods E30. Test Methods E30 should only be used for
the pattern supplied by the purchaser.The castings shall be free
analyzing those elements for which specific coverage is not
of injurious defects. Surfaces of the castings shall be free of
provided for in Test Methods E351.
burnt-on sand and shall be reasonably smooth. In other
5.4 Spectrometric techniques may also be used for analysis,
respects, the castings shall conform to whatever points may be
but should a dispute arise concerning chemical composition,
specifically agreed upon between the manufacturer and the
chemical analyses determined by Test Methods E351 and Test
purchaser.
Methods E30 shall be used for referee analysis.
10. Tension Test Specimens
6. Mechanical Properties
10.1 The round tension test specimen with 2-in. or 50-mm
6.1 Although these irons are not used primarily for their
gage length shown in Fig. 3 shall be used, except when the
strength,thetensilestrengthandBrinellhardnessareindicative
⁄2-in. (13-mm) “Y” block is used or when specimens are cut
of the correct metallurgical structure. The six types shall 3
from castings under ⁄4-in. (19.0-mm) thickness. In these cases,
conform to the requirements given in Table 2.
either of the test specimens shown in Fig. 4 shall be satisfac-
tory.
7. Magnetic Property Requirements Magnetic Property
Requirements
11. Number of Test
7.1 A convenient shop test for differentiating the various
11.1 The number of test bars cast shall be agreed upon by
...