ASTM A518/A518M-99(2012)

Standard Specification for Corrosion-Resistant High-Silicon Iron Castings

ABSTRACT
This specification covers standards for high-silicon iron castings of Grades 1, 2, and 3 intended for severe environment corrosion-resistant services. The alloy shall be produced by any melting and casting process, or combination of processes that will be capable of meeting the specified contents of carbon, manganese, silicon, chromium, molybdenum, and copper. Reference analysis methods are given for each chemical component. Transverse bend test and hydrostatic test shall be performed. Material shall conform to minimum load at center and minimum deflection at center requirements.
SCOPE
1.1 This specification covers high-silicon cast iron castings intended for corrosion-resistant service.  
1.2 This specification covers three grades as shown in Table 1. Selection of grade depends on the corrosive service to be experienced by the casting. All three grades are suited for application in severe corrosive environments. However, Grade 2 is particularly suited for application in strong chloride environments, and Grade 3 is recommended for impressed current anodes. TABLE 1 Chemical Composition    
Element
Composition, Weight %
Grade 1
Grade 2
Grade 3
Carbon  
0.65–1.10  
0.75–1.15  
0.70–1.10  
Manganese  
1.50, max  
1.50, max  
1.50, max  
Silicon  
14.20–14.75  
14.20–14.75  
14.20–14.75  
Chromium  
0.50, max  
3.25–5.00  
3.25–5.00  
Molybdenum  
0.50, max  
0.40–0.60  
0.20, max  
Copper  
0.50, max  
0.50, max  
0.50, max  
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.  
1.4 The following safety hazards caveat pertains only to the test method portion, Section 9, of this specification:  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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 30-Sep-2012
• ICS: 77.140.80 - Iron and steel castings
• Technical Committee: A04 - Iron Castings
• Drafting Committee: A04.01 - Grey and White Iron Castings

Relations

• Replaces: ASTM A518/A518M-99(2008) - Standard Specification for Corrosion-Resistant High-Silicon Iron Castings
• Effective Date: 01-Oct-2012
• Referred By: ASTM A834-95(2020) - Standard Specification for Common Requirements for Iron Castings for General Industrial Use
• Effective Date: 01-Oct-2012
• Referred By: ASTM A861-04(2023) - Standard Specification for High-Silicon Iron Pipe and Fittings
• Effective Date: 01-Oct-2012

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: A518/A518M −99 (Reapproved 2012)
Standard Specification for
Corrosion-Resistant High-Silicon Iron Castings
This standard is issued under the fixed designationA518/A518M; 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 E351 Test Methods for ChemicalAnalysis of Cast Iron—All
Types
1.1 This specification covers high-silicon cast iron castings
intended for corrosion-resistant service.
3. Ordering Information
1.2 This specification covers three grades as shown in Table
3.1 Orders for material under this specification shall include
1. Selection of grade depends on the corrosive service to be
the following information:
experienced by the casting. All three grades are suited for
3.1.1 ASTM designation and year of issue.
application in severe corrosive environments. However, Grade
3.1.2 Grade of high-silicon cast iron (see Section 5).
2 is particularly suited for application in strong chloride
3.1.3 Number of castings.
environments, and Grade 3 is recommended for impressed
3.1.4 Approximate weight of the casting.
current anodes.
3.1.5 Drawing showing the size, shape, dimensions, and
finishing details. The drawing should indicate any critical
1.3 The values stated in either SI units or inch-pound units
are to be regarded separately as standard. The values stated in dimensions and should give the allowable tolerances on all
dimensions and on the accumulation of dimensions. If the
each system may not be exact equivalents; therefore, each
system shall be used independently of the other. Combining purchaser supplies the pattern, the dimensions of the casting
shall conform to those predicted by the pattern.
values from the two systems may result in non-conformance
with the standard. 3.1.6 Options in this specification, including:
3.1.6.1 The status of the heat treatment of the castings when
1.4 The following safety hazards caveat pertains only to the
shipped by the manufacturer (see Section 7).
test method portion, Section 9, of this specification: This
3.1.6.2 If the chemical analysis and mechanical test results
standarddoesnotpurporttoaddressallofthesafetyconcerns,
are to be reported to the purchaser (see Section 14).
ifany,associatedwithitsuse.Itistheresponsibilityoftheuser
3.1.6.3 If a transverse test is required (see 8.1).
of this standard to establish appropriate safety and health
3.1.6.4 If hydraulic testing is required, and, if required, the
practices and determine the applicability of regulatory limita-
test pressure and the leakage permitted (see 8.2).
tions prior to use.
3.1.6.5 Any special packing, markings, etc.
2. Referenced Documents
4. Method of Manufacture
2.1 ASTM Standards:
4.1 The alloy may be produced by any melting and casting
A438 Test Method for Transverse Testing of Gray Cast Iron
process, or combination of processes, capable of meeting the
(Withdrawn 2003)
chemical composition and mechanical properties specified.
E350 Test Methods for Chemical Analysis of Carbon Steel,
Low-Alloy Steel, Silicon Electrical Steel, Ingot Iron, and
5. Chemical Composition
Wrought Iron
5.1 High-silicon iron castings are produced in one of three
grades, as given in Table 1 of this specification.
This specification is under the jurisdiction of ASTM Committee A04 on Iron
CastingsandisthedirectresponsibilityofSubcommitteeA04.01onGreyandWhite
6. Chemical Analysis
Iron Castings.
Current edition approved Oct. 1, 2012. Published November 2012. Originally
6.1 Heat Analysis—Chemical analysis of each heat (or each
approved in 1964. Last previous edition approved in 2008 as A518/A518M – 99
tap, if from a continuous melting operation) shall be made by
(2008). DOI: 10.1520/A0518_A0518M-99R12.
the manufacturer to determine the percentages of the elements
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
specified in Table 1. The analysis shall be made from a test
Standards volume information, refer to the standard’s Document Summary page on
sample cast during the pouring of the heat (or tap). The
the ASTM website.
3 chemical composition thus determined shall conform to the
The last approved version of this historical standard is referenced on
www.astm.org. requirements specified for that grade in Table 1.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A518/A518M − 99 (2012)
TABLE 1 Chemical Composition
6.4.5 Chromium:
Element Composition, Weight % 6.4.5.1 Mill, lathe, or pulverize the sample to pass through
Grade 1 Grade 2 Grade 3 a 100-mesh sieve.
Carbon 0.65–1.10 0.75–1.15 0.70–1.10 6.4.5.2 Determine chromium in accordance with the sec-
Manganese 1.50, max 1.50, max 1.50, max
tions on Chromium by the Peroxydisulfate-Oxidation Titrimet-
Silicon 14.20–14.75 14.20–14.75 14.20–14.75
ric Method in Test Methods E350, except dissolve the sample
Chromium 0.50, max 3.25–5.00 3.25–5.00
Molybdenum 0.50, max 0.40–0.60 0.20, max
as follows:
Copper 0.50, max 0.50, max 0.50, max
(a) Place the appropriate amount of weighed sample into a
600-mLGriffin beaker or 500-mLvolumetric flask.Add 20 mL
of nitric acid (HNO ) and carefully add HF, dropwise, until the
reaction ceases. A TFE-fluorocarbon beaker may be used if
6.2 Product Analysis—A product analysis may be made by
desired.
the purchaser from material representing each heat, lot, or
(b) Add30mLof1+1 sulfuric acid (H SO),5mLof
casting. The sample for such analysis shall be taken as desired
2 4
phosphoric acid (H PO ), and boil until light fumes of H SO
by the purchaser. The chemical composition thus determined
3 4 2 4
are present and the sample is completely dissolved.
shall meet the requirements for the grade specified.
(c) Cool the solution, add 150 mL of water, heat to
6.3 Routine Analysis Methods—Spectrometric and other
dissolve if necessary, and continue as in Test Methods E350.
instrumental methods or wet chemical laboratory methods are
6.4.6 Copper:
acceptable for routine and control determinations, but shall be
6.4.6.1 Mill, lathe, or pulverize the sample to pass through
standardizedagainstandgiveessentiallythesameresultsasthe
a 100-mesh sieve.
methods specified in 6.4.
6.4.6.2 Determine the copper in accordance with the sec-
6.4 Reference Analysis Methods:
tions on Copper by the Sulfide Precipitation-Electrodeposition
6.4.1 Silicon:
Gravimetric Method in Test Methods E350,or
6.4.1.1 Analyze samples soluble when processed in accor-
6.4.6.3 Determine the copper in accordance with the sec-
dance with Test Methods E350, by that method, except as
tions on Copper by the Neocuproine Photometric Method, in
follows:
Test Methods E350.Add HF as required for complete solution
(a) The sample weight shall be 0.3 g with a weight
of the sample.
tolerance of 60.1 mg.
(b) Pulverize one or more pieces of the sample until the
7. Heat Treatment
entire material in the piece or pieces passes through a 100-
7.1 High-silicon iron castings are generally used in the
mesh screen.
heat-treated (stress-relieved) condition. Small castings of
(c) Dissolve the sample in 25 mL of perchloric acid.
simple configuration not conducive to high-residual stresses
6.4.1.2 Analyze samples that are not soluble when pro-
may be used in the as-cast condition. If the castings are to be
cessed in accordance with 6.4.1.1 in accordance with Annex
supplied in the stress-relieved condition, the purchaser must so
A1.
specify.
6.4.2 Molybdenum:
6.4.2.1 Mill, lathe, or pulverize the sample to pass through 7.2 At its option, the foundry may heat treat the castings to
a 100-mesh sieve. If the sample is soluble when processed in
remove stresses without the purchaser so specifying.
accordance with Test Methods E350, use this method.
7.3 If used, the stress-relieving heat treatment shall be as
6.4.2.2 If the sample is not acid-soluble when processed in
follows:
accordance with 6.4.2.1, proceed as follows:
7.3.1 Heat at a rate that will not crack the castings.
(a) Use the appropriate weight of sample in accordance
7.3.2 Hold the castings at a minimum temperature of
with6.4.2.1insteadoftheweightgiveninA1.2.3ofAnnexA1.
1600°F [870°C] for a minimum period of 1 h/in. [mm] of
(b) Fuse the sample in accordance with A1.2.1 and A1.2.2
maximum section thickness, except that in no case shall the
and A1.2.4 – A1.2.12 of Annex A1.
holding period be less than 2 h.
(c) Add the amount of dissolving acid(s), specified in the
7.3.3 Cool the castings to 400°F [205°C] maximum at a rate
sections in Molybdenum by the Photometric Method in Test
not faster than 100°F [55°C]/15 min.
Methods E350, heat to fumes of perchloric acid. Proceed in
7.3.4 From 400°F [205°C] to ambient temperature, the
accordance with Test Methods E350.
castings may be cooled in still ambient air.
6.4.3 Carbon—Determine carbon in accordance with sec-
tions on Carbon, Total, by the Combustion Gravimetric
8. Mechanical Requirements
Method, in Test Methods E350.
6.4.4 Manganese: 8.1 Transverse Bend Test:
8.1.1 Whenspecifiedbythepurchaser,thesilicon-ironalloy
6.4.4.1 Mill, lathe, or pulverize the sample to pass through
a 100-mesh sieve. shall be given a transverse bend test.The specimen tested shall
meet the test requirements prescribed in Table 2.
6.4.4.2 Determine manganese in accordance with the sec-
tions on Manganese by the Peroxydisulfate-Arsenite Titrimet- 8.1.2 When transverse bend tests are specified, test bars
ric Method in Test Methods E350. Add hydrofluoric acid as shall be made and tested from each heat (or ladle in the case of
required for complete solution of the (HF) sample. continuous melting) from which the castings are poured.
A518/A518M − 99 (2012)
TABLE 2 Transverse Bend Test Minimum Requirements
9.2.1 Do not machine the specimen.
9.2.2 The specimen shall be sufficiently smooth, round, and
NOTE 1—Test bars are to be tested on supports 12 in. [3.5 mm] apart.
straight to permit testing without machining.
Load at center, min, lbf [N] 930 [4090]
Deflection at center, min, in. [mm] 0.026 [0.66] 9.2.3 Produce the specimen in accordance with Fig. 1.
9.2.4 The specimen shall conform to the dimensions shown
in Fig. 2.
9.2.5 Report the actual breaking load without use of a
8.1.3 The test bars shall be heat treated in the production
correction factor. The requirements of Table 2 allow for
furnaces to the same procedure as the castings.
deviation due to variations in test bar diameter. In the same
8.1.4 Each test bar shall be permanently marked with the
sense, measure and report the deflection at fracture without
heat or ladle number from which it was poured. Marking shall
correction.
be accomplished with cast digits, with a vibratory marking
9.2.6 Apply the load at a rate such that a 0.025-in. [0.65-
tool, or with a felt-point pen using indelible ink.
mm] deflection is produced in 50 to 70 s. Continue loading at
8.2 Hydrostatic Test—When specified by the purchaser,
the same head-movement rate until the specimen fractures.
subject the castings for critical applications involving pressure
or vacuum conditions to a hydrostatic pressure test at a
10. Workmanship, Finish, and Appearance
minimum of 40 psig [275 kPa]. Any leak revealed by this test
shall be cause for rejection of the casting. 10.1 The workmanship and finish shall be as agreed upon
between the manufacturer and the purchaser.
9. Transverse Bend Test Method
9.1 When a requirement for transverse bend tests has been 11. Number of Tests and Retests
agreed upon between the purchaser and the manufacturer, the
11.1 If a valid test specimen fails to conform to this
manufacturer shall test transverse bend bar(s) from each heat.
specification, two retests shall be made. If either retest fails to
9.2 Conduct the transverse bend test in accordance with conform to this specification, the castings represented by these
Method A438, except as follows: test bars shall be rejected.
FIG. 1 Suggested Pattern for Transverse Bend Test Bar, Cast Horizontally, 1.20 in. [30.5 mm] in Diameter
A518/A518M − 99 (2012)
12.2 The manufacturer shall inspect the material covered by
this specification prior to shipment and, upon request, shall
furnish the purchaser with a certification of test(s).
13. Rejection and Rehearing
13.1 Rejection—Any rejection based on test reports shall be
reported to the manufacturer within 30 days from the receipt of
NOTE 1—It is recommended that the casting be mold-cooled to below
1000°F [540°C] before shakeout, and that the test bars be stress-relieved the test report by the purchaser. The manufacturer shall be
before transverse testing.
advised within one week of purchaser’s discovery of material
FIG. 2 Transverse Bend Test Bar Dimensions
that contains injurious defects. The purchaser shall hold the
material a minimum of 30 days pending action by the manu-
11.2 If after testing, a test specimen shows evidence of a
facturer.
defect, the results of the test may be regarded as invalid and
another test made.
13.2 Rehearing—Samples tested in accordance with this
specification that represent rejected material shall be preserved
11.3 In the absence of further separately cast test bars, the
for two weeks from the date of the test report. In case of
manufacturer shall have the option of submitting test bars
dissatisfaction with the results of the test, the manufacturer
sectioned from an agreed-upon position in the castings.
may make a claim for a rehearing within that time.
11.4 If reheat treatment is required to meet the specification,
castingsandtheirrepresentativetestbarsshallbereheattreated
14. Certification
together. Testing will then proceed as in 11.1, 11.2, and 11.3.
14.1 When specified by the purchaser, the manufacturer
12. Inspection
shall provide the purchaser with a certification stating that the
12.1 When specified in the purchase order, the inspector
castingsmeetthespecifiedrequirements.Thecertificationshall
representing the purchaser shall have access to the material
include the results of any chemical analyses and mechanical
subjecttoinspectionforthepurposeofwitnessingtheselection
tests.
of the samples, the preparation of the test pieces, and the
performance of the test(s). For such tests, the inspector shall
15. Product Marking
have the right to indicate the pieces from which the samples
15.1 Thetrademarkofthemanufacturershallbelegiblycast
will be taken in accordance with the provisions of this
specifica
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