ASTM A48/A48M-03(2008)
(Specification)Standard Specification for Gray Iron Castings
Standard Specification for Gray Iron Castings
ABSTRACT
This specification covers gray iron castings intended for general engineering use where tensile strength is a major consideration. Castings are classified on the basis of the tensile strength of the iron in separately cast test bars. The surface of the casting shall be free of adhering sand, scale, cracks, and hot tears, as determined by visual examination. The test bars are designated into S, A, B, and C categories, according to the thickness of its controlling wall section. The casting shall be subjected to a tension test to determine its tensile strength.
SCOPE
1.1 This specification covers gray iron castings intended for general engineering use where tensile strength is a major consideration. Castings are classified on the basis of the tensile strength of the iron in separately cast test bars.
1.1.1 This specification subordinates chemical composition to tensile strength.
1.2 Castings produced to this specification are graded on the basis of minimum tensile strength obtained in special test coupons designed to standardize cooling rate. The tensile strength developed in certain casting sections may vary from test coupon values (see X1.2).
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 non-conformance with the standard.
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Designation:A48/A48M −03(Reapproved 2008)
Standard Specification for
Gray Iron Castings
This standard is issued under the fixed designation A48/A48M; 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.
This specification replaces Federal Specification QQ-I-652.
1. Scope 3.1.1 Definitions for many terms common to gray iron
castings are found in Terminology A644.
1.1 This specification covers gray iron castings intended for
general engineering use where tensile strength is a major
4. Classification
consideration. Castings are classified on the basis of the tensile
4.1 Castings ordered and produced in accordance with this
strength of the iron in separately cast test bars.
specificationareclassifiedintoanumberofgradesbasedonthe
1.1.1 This specification subordinates chemical composition
properties of separately cast test bars (Table 1, Table 2). Each
to tensile strength.
class is designated by a number followed by a letter. The
1.2 Castings produced to this specification are graded on the
number indicates the minimum tensile strength of the sepa-
basis of minimum tensile strength obtained in special test
rately cast test bar, and the letter indicates the size of the test
coupons designed to standardize cooling rate. The tensile
bar. Examples of proper designations are as follows:
strength developed in certain casting sections may vary from
Gray Iron Castings, ASTM Specification A48, Class 30B.
test coupon values (see X1.2).
Gray Iron Castings, ASTM Specification A48, Class 40C.
1.3 The values stated in either SI units or inch-pound units
5. Ordering Information
are to be regarded separately as standard. The values stated in
5.1 Orders for material to this specification shall include the
each system may not be exact equivalents; therefore, each
following information:
system shall be used independently of the other. Combining
5.1.1 ASTM designation number and year of issue,
values from the two systems may result in non-conformance
5.1.2 Class of iron required (see 4.1, Table 1, and Table 2),
with the standard.
5.1.3 The size of the separately cast test bar (letter
classification—A, B, C, or S) that best represents the thickness
2. Referenced Documents
of the controlling section of the casting (see Table 3),
2.1 ASTM Standards:
5.1.4 The tension test specimen (B or C) to be machined
A644 Terminology Relating to Iron Castings
from test bar C (see 13.3, Table 4, and Fig. 1),
E8 Test Methods for Tension Testing of Metallic Materials
5.1.5 The tension test specimen to be machined from test
2.2 Military Standard:
bar S (see 13.4, Table 4, and Fig. 1),
MIL-STD-129 Marking for Shipment and Storage
5.1.6 Lot size (see Section 10),
5.1.7 Special requirements (see Section 6),
2.3 Federal Standard:
5.1.8 Saving tested specimens or unbroken test bars (see
Federal Standard No. 123 Marking for Shipment (Civil
15.1), and
Agencies)
5.1.9 Special preparation for delivery (see Section 19).
3. Terminology
6. Special Requirements
3.1 Definitions:
6.1 When agreed upon in writing between the manufacturer
and the purchaser, it may be necessary for the castings to meet
special requirements as to hardness, chemical composition,
This specification is under the jurisdiction of ASTM Committee A04 on Iron
microstructure, pressure tightness, radiographic soundness,
CastingsandisthedirectresponsibilityofSubcommitteeA04.01onGreyandWhite
dimensions, surface finish, and so forth.
Iron Castings.
Current edition approved Oct. 1, 2008. Published November 2008. Originally
7. Tensile Requirements
approved in 1905. Last previous edition approved in 2003 as A48/A48M – 03. DOI:
10.1520/A0048_A0048M-03R08.
7.1 Test bars representing castings conforming to this speci-
Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,
fication shall meet the requirements for tensile strength as
Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http://
www.dodssp.daps.mil. described in Table 1 and Table 2.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A48/A48M−03 (2008)
TABLE 1 Requirements for Tensile Strength of Gray Cast Irons in TABLE 2 Requirements for Tensile Strength of Gray Cast Irons in
Separately Cast Test Bars (Inch-Pound) Separately Cast Test Bars (Metric)
Tensile Strength, Nominal Test Bar Tensile Strength, Nominal Test Bar
Class Class
min, ksi Diameter, in. min, ksi [MPa] Diameter, in. [mm]
No. 20 A 20 0.8 No. 150A 150 20 to 22
No. 20 B 1.2 No. 150B 30
No. 20 C 2.0 No. 150C 50
A A
No. 20 S Bars S No. 150S Bars S
No. 25 A 25 0.88 No. 175A 175 20 to 22
No. 25 B 1.2 No. 175B 30
No. 25 C 2.0 No. 175C 50
A A
No. 25 S Bars S No. 175S Bars S
No. 30 A 30 0.88 No. 200A 200 20 to 22
No. 30 B 1.2 No. 200B 30
No. 30 C 2.0 No. 200C 50
A A
No. 30 S Bars S No. 200S Bars S
No. 35 A 35 0.88 No. 225A 225 20 to 22
No. 35 B 1.2 No. 225B 30
No. 35 C 2.0 No. 225C 50
A A
No. 35 S Bars S No. 225S Bars S
No. 40 A 40 0.88 No. 250A 250 20 to 22
No. 40 B 1.2 No. 250B 30
No. 40 C 2.0 No. 250C 50
A A
No. 40 S Bars S No. 250S Bars S
No. 45 A 45 0.88 No. 275A 275 20 to 22
No. 45 B 1.2 No. 275B 30
No. 45 C 2.0 No. 275C 50
A A
No. 45 S Bars S No. 275S Bars S
No. 50 A 50 0.88 No. 300A 300 20 to 22
No. 50 B 1.2 No. 300B 30
No. 50 C 2.0 No. 300C 50
A A
No. 50 S Bars S No. 300S Bars S
No. 55 A 55 0.88 No. 325A 325 20 to 22
No. 55 B 1.2 No. 325B 30
No. 55 C 2.0 No. 325C 50
A A
No. 55 S Bars S No. 325S Bars S
No. 60 A 60 0.88 No. 350A 350 20 to 22
No. 60 B 1.2 No. 350B 30
No. 60 C 2.0 No. 350C 50
A A
No. 60 S Bars S No. 350S Bars S
A
AlldimensionsoftestbarSshallbeasagreeduponbetweenthemanufacturer
No. 375A 375 20 to 22
and the purchaser.
No. 375B 30
No. 375C 50
A
No. 375S Bars S
No. 400A 400 20 to 22
8. Dimensional Requirements No. 400B 30
No. 400C 50
A
8.1 The castings shall conform to the dimensions or draw-
No. 400S Bars S
ings furnished by the purchaser, or, if there are no drawings, to A
AlldimensionsoftestbarSshallbeasagreeduponbetweenthemanufacturer
and the purchaser.
the dimensions predicted by the pattern equipment supplied by
the purchaser.
10.1.1 All the metal poured from a single heating in a batch
9. Workmanship and Finish
type melting furnace.
9.1 The surface of the casting shall be free of adhering sand,
10.1.2 All the metal from two or more batch type melting
scale, cracks, and hot tears, as determined by visual examina-
furnaces poured into a single ladle or a single casting.
tion.
10.1.3 All the metal poured from a continuous melting
9.2 No repairing by plugging or welding of any kind shall
furnace for a given period of time between changes in charge,
be permitted unless written permission is granted by the
processing conditions, or aim-for chemistry or 4 h, whichever
purchaser.
is the shorter period.
10.1.3.1 The purchaser may agree to extend the 4-h time
10. Sampling
period to8hifthe manufacturer can demonstrate sufficient
10.1 A lot shall consist of one of the following: process control to warrant such an extension.
A48/A48M−03 (2008)
TABLE 3 Separately Cast Test Bars for Use When a Specific
12.3 If the results of a valid test fail to conform to the
Correlation Has Not Been Established Between the Test Bar and
requirements of this specification, two retests shall be made. If
the Casting
either retest fails to meet the specification requirements, the
Thickness of the Wall of the Controlling
Test Bar castings represented by these test specimens shall be rejected.
Section of the Casting, in. [mm]
A valid test is one wherein the specimen has been properly
Under 0.25 [under 5] S
prepared and appears to be sound and on which the approved
0.25 to 0.50 [5 to 14] A
0.51 to 1.00 [15 to 25] B
test procedure has been followed.
1.01 to 2 [26 to 50] C
Over 2 [over 50] S 12.4 Ifsufficientseparatelycasttestpiecesarenotavailable,
the manufacturer shall have the option of removing a test
specimen from a location of representative casting, as agreed
upon between the manufacturer and purchaser.
12.5 If the first test results indicate that a heat treatment is
11. Cast Test Bars
needed to meet the test requirements, the entire lot of castings
11.1 Test bars shall be separate castings poured from the
and the representative test specimens shall be heat treated
same lot as the castings they represent and shall have dimen-
together. Testing shall proceed in accordance with 12.1-12.3.
sions as shown in Table 4. Allowance may be made for
12.6 If, after testing, a test specimen shows evidence of a
reasonablepatterndraftwithinthetolerancesshowninTable4.
defect, the results of the test may be invalidated and another
Test bars A, B, and C are all standard test bars in the form of
made on a specimen from the same lot.
simple cylinders. Test bar S is special and is intended for use
where the standard bars are not satisfactory.
13. Tension Test Specimens
11.2 The test bars shall be cast in dried, baked, or chemi-
13.1 For test Bar A, the tension-test specimen A, as shown
cally bonded molds made mainly of an aggregate of siliceous
in Fig. 1, shall be machined concentric with the axis of the test
sand with appropriate binders. The average grain size of the
bar.
sand shall approximate that of the sand in which the castings
are poured. Molds for the test bars shall be approximately at
13.2 For test Bar B, the tension test specimen B, as shown
room temperature when poured. More than one test bar may be
in Fig. 1, shall be machined concentric with the axis of the test
cast in a single mold, but each bar in the mold shall be
bar.
surrounded by a thickness of sand which is not less than the
13.3 For test Bar C, tension test specimens B or C, as shown
diameter of the bar. A suitable design for a mold is shown in
in Fig. 1, shall be machined concentric with the axis of the test
Fig. 2.
bar.Unlessthesizeofthetensiontestspecimentobemachined
NOTE 1—The intent of these provisions is as follows: to prohibit the
from test bar C is specified in writing by the purchaser, the
casting of test bars in molds of metal, graphite, zircon, light-weigh
...
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:A48/A48M–00 Designation: A 48/A 48M – 03 (Reapproved 2008)
Standard Specification for
Gray Iron Castings
This standard is issued under the fixed designation A 48/A 48M; 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. This specification replaces Federal Specification
QQ-I-652.
1. Scope
1.1 This specification covers gray iron castings intended for general engineering use where tensile strength is a major
consideration. Castings are classified on the basis of the tensile strength of the iron in separately cast test bars.
1.1.1 This specification subordinates chemical composition to tensile strength.
1.2 Castings produced to this specification are graded on the basis of minimum tensile strength obtained in special test coupons
designed to standardize cooling rate. The tensile strength developed in certain casting sections may vary from test coupon values
(see X1.2).
1.3 The values stated in either inch-poundSI units or SIinch-pound units are to be regarded separately as standard. Within the
text, the SI units are shown in brackets. The values stated in each system aremay not be exact equivalents; therefore, each system
shall be used independently of the other. Combining values from the two systems may result in non-conformance with the
specification. standard.
2. Referenced Documents
2.1 ASTM Standards:
A 644 Terminology Relating to Iron Castings
E 8 Test Methods for Tension Testing of Metallic Materials
2.2 Military Standard:
MIL-STD-129 Marking for Shipment and Storage
2.3 Federal Standard:
Federal Standard No. 123 Marking for Shipment (Civil Agencies)
3. Terminology
3.1 Definitions:
3.1.1 Definitions for many terms common to gray iron castings are found in Terminology A 644.
4. Classification
4.1 Castings ordered and produced in accordance with this specification are classified into a number of grades based on the
properties of separately cast test bars (Table 1, Table 2). Each class is designated by a number followed by a letter. The number
indicates the minimum tensile strength of the separately cast test bar, and the letter indicates the size of the test bar. Examples of
proper designations are as follows:
Gray Iron Castings, ASTM Specification A 48, Class 30B.
Gray Iron Castings, ASTM Specification A 48, Class 40C.
5. Ordering Information
5.1 Orders for material to this specification shall include the following information:
5.1.1 ASTM designation number and year of issue,
5.1.2 Class of iron required (see 4.1and , Table 1, and Table 2),
This specification is under the jurisdiction of ASTM Committee A04 on Iron Castings and is the direct responsibility of Subcommittee A04.01 on Gray Iron Castings.
Current edition approved May 10, 2000. Published June 2000. Originally published as A48–05. Last previous edition A48–94a.
This specification is under the jurisdiction of ASTM Committee A04 on Iron Castings and is the direct responsibility of Subcommittee A04.01 on Grey and White Iron
Castings.
Current edition approved Oct. 1, 2008. Published November 2008. Originally approved in 1905. Last previous edition approved in 2003 as A 48/A 48M – 03.
Annual Book of ASTM Standards, Vol 01.02.
Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http://www.dodssp.daps.mil.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
A 48/A 48M – 03 (2008)
TABLE 1 Requirements for Tensile Strength of Gray Cast Irons
in Separately Cast Test Bars (Inch-Pound)
Tensile Strength, Nominal Test Bar
Class
min, ksi [MPa] Diameter, in. [mm]
No. 20 A 20 (138) 0.88 (22.4)
No. 20 A 20 0.8
No. 20 B 1.2 (30.5)
No. 20 B 1.2
No. 20 C 2.0 (50.8)
No. 20 C 2.0
A
No. 20 S Bars S
No. 25 A 25 (172) 0.88 (22.4)
No. 25 A 25 0.88
No. 25 B 1.2 (30.5)
No. 25 B 1.2
No. 25 C 2.0 (50.8)
No. 25 C 2.0
A
No. 25 S Bars S
No. 30 A 30 (207) 0.88 (22.4)
No. 30 A 30 0.88
No. 30 B 1.2 (30.5)
No. 30 B 1.2
No. 30 C 2.0 (50.8)
No. 30 C 2.0
A
No. 30 S Bars S
No. 35 A 35 (241) 0.88 (22.4)
No. 35 A 35 0.88
No. 35 B 1.2 (30.5)
No. 35 B 1.2
No. 35 C 2.0 (50.8)
No. 35 C 2.0
A
No. 35 S Bars S
No. 40 A 40 (276) 0.88 (22.4)
No. 40 A 40 0.88
No. 40 B 1.2 (30.5)
No. 40 B 1.2
No. 40 C 2.0 (50.8)
No. 40 C 2.0
A
No. 40 S Bars S
No. 45 A 45 (310) 0.88 (22.4)
No. 45 A 45 0.88
No. 45 B 1.2 (30.5)
No. 45 B 1.2
No. 45 C 2.0 (50.8)
No. 45 C 2.0
A
No. 45 S Bars S
No. 50 A 50 (345) 0.88 (22.4)
No. 50 A 50 0.88
No. 50 B 1.2 (30.5)
No. 50 B 1.2
No. 50 C 2.0 (50.8)
No. 50 C 2.0
A
No. 50 S Bars S
No. 55 A 55 (379) 0.88 (22.4)
No. 55 A 55 0.88
No. 55 B 1.2 (30.5)
No. 55 B 1.2
No. 55 C 2.0 (50.8)
No. 55 C 2.0
A
No. 55 S Bars S
No. 60 A 60 (414) 0.88 (22.4)
No. 60 A 60 0.88
No. 60 B 1.2 (30.5)
No. 60 B 1.2
No. 60 C 2.0 (50.8)
No. 60 C 2.0
A
No. 60 S Bars S
A
AlldimensionsoftestbarSshallbeasagreeduponbetweenthemanufacturer
and the purchaser.
A 48/A 48M – 03 (2008)
TABLE 2 Requirements for Tensile Strength of Gray Cast Irons
in Separately Cast Test Bars (Metric)
Tensile Strength, Nominal Test Bar
Class
min, ksi [MPa] Diameter, in. [mm]
No. 150A 150 20 to 22
No. 150B 30
No. 150C 50
A
No. 150S Bars S
No. 175A 175 20 to 22
No. 175B 30
No. 175C 50
A
No. 175S Bars S
No. 200A 200 20 to 22
No. 200B 30
No. 200C 50
A
No. 200S Bars S
No. 225A 225 20 to 22
No. 225B 30
No. 225C 50
A
No. 225S Bars S
No. 250A 250 20 to 22
No. 250B 30
No. 250C 50
A
No. 250S Bars S
No. 275A 275 20 to 22
No. 275B 30
No. 275C 50
A
No. 275S Bars S
No. 300A 300 20 to 22
No. 300B 30
No. 300C 50
A
No. 300S Bars S
No. 325A 325 20 to 22
No. 325B 30
No. 325C 50
A
No. 325S Bars S
No. 350A 350 20 to 22
No. 350B 30
No. 350C 50
A
No. 350S Bars S
No. 375A 375 20 to 22
No. 375B 30
No. 375C 50
A
No. 375S Bars S
No. 400A 400 20 to 22
No. 400B 30
No. 400C 50
A
No. 400S Bars S
A
AlldimensionsoftestbarSshallbeasagreeduponbetweenthemanufacturer
and the purchaser.
5.1.3 The size of the separately cast test bar (letter classification—A, B, C, or S) that best represents the thickness of the
controlling section of the casting (see Table 2Table 3),
5.1.4 The tension test specimen (B or C) to be machined from test bar C (see 13.3, Table 3Table 4, and Fig. 1),
5.1.5 The tension test specimen to be machined from test bar S (see 13.4, Table 3Table 4, and Fig. 1),
5.1.6 Lot size (see Section 10),
5.1.7 Special requirements (see Section 6),
5.1.8 Saving tested specimens or unbroken test bars (see 15.1), and
5.1.9 Special preparation for delivery (see Section 19).
6. Special Requirements
6.1 When agreed upon in writing between the manufacturer and the purchaser, it may be necessary for the castings to meet
A 48/A 48M – 03 (2008)
TABLE 2 3 Separately Cast Test Bars for Use When a Specific
Correlation Has Not Been Established Between the Test Bar and
the Casting
Thickness of the Wall of the Controlling
Test Bar
Section of the Casting, in. [mm]
Under 0.25 [under 6] S
Under 0.25 [under 5] S
0.25 to 0.50 [6 to 13] A
0.25 to 0.50 [5 to 14] A
0.51 to 1.00 [13 to 25] B
0.51 to 1.00 [15 to 25] B
1.01 to 2 [26 to 51] C
1.01 to 2 [26 to 50] C
Over 2 [over 51] S
Over 2 [over 50] S
TABLE 3 4 Diameters and Lengths of Cast Test Bars
As-Cast Diameter, in. [mm] Length, in. [mm]
Test Bar
Nominal Minimum Maximum
Minimum (Bottom) Maximum (Top)
(Mid-Length) (Specified) (Recommended)
A 0.88 [22.5] 0.85 [21.5] 0.96 [24.5] 5.0 [125] 6.0 [150]
A 0.88 [22.4] 0.85 [21.6] 0.96 [24.4] 5.0 [125] 6.0 [150]
B 1.20 [30.5] 1.14 [29.0] 1.32 [33.5] 6.0 [150] 9.0 [230]
C 2.00 [50.8] 1.90 [48.3] 2.10 [53.3] 7.0 [175] 10.0 [255]
A
S . . . . .
A
All dimensions of test bar S shall be as agreed upon by the manufacturer and the purchaser.
Tension Test Tension Test Tension Test
Dimensions, in. [mm]
Specimen A Specimen B Specimen C
G—Length of parallel, min 0.50 [13] 0.75 [19] 1.25 [32]
D—Diameter 0.500 6 0.010 0.750 6 0.015 1.25 6 0.025
[12.7 6 0.25] [19.0 6 0.38] [30 6 0.65]
[13 6 0.25] [20 6 0.4] [30 6 0.6]
R—Radius of fillet, min 1 [25] 1 [25] 2 [50]
1 1 1
A—Length of reduced section, min 1 ⁄4 [32] 1 ⁄2 [38] 2 ⁄4 [57]
3 3
L—Over-all length, min 3 ⁄4 [95] 4 [100] 6 ⁄8 [160]
7 1 7
C—Diameter of end section, approx ⁄8 [22] 1 ⁄4 [32] 1 ⁄8 [48]
7 1 7
C—Diameter of end section, approx ⁄8 [20] 1 ⁄4 [20] 1 ⁄8 [47]
1 1 5
E—Length of shoulder, min ⁄4 [6] ⁄4 [6] ⁄16 [8]
5 1 15 1 7 1
F—Diameter of shoulder ⁄8 6 ⁄64 ⁄16 6 ⁄64 1 ⁄16 6 ⁄64
[16 6 0.4] [25 6 0.4] [36 6 0.4]
[16 6 0.4] [24 6 0.4] [36 6 0.4]
AA A
B—Length of end section
A
Optional to fit holders on testing machine. If threaded, root diameter shall not be less than dimension F.
FIG. 1 Tension-Test Specimens
special requirements as to hardness, chemical composition, microstructure, pressure tightness, radiographic soundness, dimen-
sions, surface finish, etc. and so forth.
A 48/A 48M – 03 (2008)
7. Tensile Requirements
7.1 Test bars representing castings conforming to this specification shall meet the requirements for tensile strength as described
in Table 1 and Table 2.
8. Dimensional Requirements
8.1 The castings shall conform to the dimensions or drawings furnished by the purchaser, or, if there are no drawings, to the
dimensions predicted by the pattern equipment supplied by the purchaser.
9. Workmanship and Finish
9.1 The surface of the casting shall be free of adhering sand, scale, cracks, and hot tears, as determined by visual examination.
9.2 No repairing by plugging or welding of any kind shall be permitted unless written permission is granted by the purchaser.
10. Sampling
10.1 A lot shall consist of one of the following:
10.1.1 All the metal poured from a single heating in a batch type melting furnace.
10.1.2 All the metal from two or more batch type melting furnaces poured into a single ladle or a single casting.
10.1.3 All the metal poured from a continuous melting furnace for a given period of time between changes in charge, processing
conditions, or aim-for chemistry or 4 h, whichever is the shorter period.
10.1.3.1 The purchaser may agree to extend the 4-h time period to8hifthe manufacturer can demonstrate sufficient process
control to warrant such an extension.
11. Cast Test Bars
11.1 Test bars shall be separate castings poured from the same lot as the castings they represent and shall have dimensions as
shown in Table 3Table 4.Allowance may be made for reasonable pattern draft within the tolerances shown in Table 3Table 4. Test
bars A, B, and C are all standard test bars in the form of simple cylinders. Test bar S is special and is intended for use where the
standard bars are not satisfactory.
11.2 The test bars shall be cast in dried, baked, or chemically bonded molds made mainly of an aggregate of siliceous sand with
appropriate binders. The average grain size of the sand shall approximate that of the sand in which the castings are poured. Molds
for the test bars shall be approximately at room temperature when poured. More than one test bar may be cast in a single mold,
but each bar in the mold shall be surrounded by a thickness of sand which is not less than the diameter of the bar.Asuitable design
for a mold is shown in Fig. 2.
NOTE 1—The intent of these provisions is as follows: to prohibit the casting of test bars in molds of metal, graphite, zircon, light-weight aggregates,
or other materials which would significantly affect the tensile strength of the iron; to prohibit control of tensile strength of the test bars by manipulation
of the grain size of the sand; and to prohibit the casting of test bars in molds preheated substantially above room temperature.
Required Features: Optional Features:
1. Material—Aggregate of dry siliceous sand. 1. Number of test bars in a single mold—Two suggested.
2. Position—Bars vertical. 2. Design of pouring cup.
3. L—See Table 3. 3. P—2 in. [50 mm], suggested.
3. L—See Table 4. 3. P—2 in. [50 mm], suggested.
4. D—See Table 3. 4. N— ⁄16 in. [8 mm] in diameter, suggested.
4. D—See Table 4. 4. N— ⁄16 in. [8 mm] in diameter, suggested.
5. W—Not less than diameter D.f5. M=1.5 N, suggested.
FIG. 2 Suitable Design and Dimensions for Mold for Separately Cast Cylindrical Test Bars for Gray Iron
A 48/A 48M – 03 (2008)
11.3 Test bars that are intended to represent castings that are cooled in the mold to less than 900°F [480°C], before shakeout,
shall be cooled in their molds to a temperature less than 900°F [480°C]. They then may be cooled in still air to room temperature.
11.4 Test bars that are intended to represent castings that are hotter than 900°F [480°C], when shaken out of their molds, shall
be cooled as described in 11.3 or (by agreement between the manufacturer and the purchaser) may be shaken out of their molds
at approximately the same temperature as the castings they represent.
11.5 When castings are stress-relieved, annealed, or otherwise heat-treated, test bars shall receive the same thermal treatment
and shall be treated adjacent to the castings they represent.
12. Number of Tests and Retests
12.1 The tension test shall be conducted in accordance with Test Method E 8.
12.2 One tension test shall be performed on each lot and shall conform to the tensile requirements specified.
12.3 If the results of a valid test fail to conform to the requirements of this specification, two retests shall be made. If either
retest fails to meet the specification requirements, the castings represented by these test specimens shall be rejected. A valid test
is one wherein the specimen has been properly prepared and appears to be sound and on which the approved test procedure has
been followed.
12.4 If sufficient separately cast test pieces are not available, the manufacturer shall have the option of removing a test specimen
from a location of representative casting, as agreed upon between the manufacturer and purchaser.
12.5 If the first test results indicate that a heat treatment is needed to meet the test requirements, the entire lot of castings and
the representative test specimens shall be heat treated together. Testi
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