ASTM B418-16a(2021)

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.
Designation:B418 −16a (Reapproved 2021)
Standard Specification for
Cast and Wrought Galvanic Zinc Anodes
This standard is issued under the fixed designation B418; 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 2. Referenced Documents
2.1 ASTM Standards:
1.1 This specification covers cast and wrought galvanic zinc
B6 Specification for Zinc
anodes used for the cathodic protection of more noble metals
B899 Terminology Relating to Non-ferrous Metals and Al-
and alloys in sea water, brackish water, other saline
loys
electrolytes, or other corrosive environments.
B949 Specification for General Requirements for Zinc and
1.2 Type I anodes are most commonly used for such
Zinc Alloy Products
applications. The Type I anode composition in this specifica-
E29 Practice for Using Significant Digits in Test Data to
tion meets the chemical composition requirements of MIL-A-
Determine Conformance with Specifications
18001K.
E527 Practice for Numbering Metals and Alloys in the
Unified Numbering System (UNS)
1.3 Zinc anodes conforming to this specification may be
E536 Test Methods for Chemical Analysis of Zinc and Zinc
used in other waters, electrolytes, backfills, and soils where
Alloys
experiencehasshownthatthespecifiedcompositionisefficient
2.2 Military Standard:
and reliable. Type II anodes are most commonly used for such
MIL-A-18001K w/INT. AMENDMENT 3, 24 October
applications.
2007 Military SpecificationAnodes Sacrificial ZincAlloy
1.4 The values stated in inch-pound units are to be regarded 4
2.3 ISO Standards:
as standard. The values given in parentheses are mathematical
ISO 3815-1 Zinc and zinc alloys — Part 1:Analysis of solid
conversions to SI units that are provided for information only
samples by optical emission spectrometry
and are not considered standard.
ISO 3815-2 Zinc and zinc alloys — Part 2: Analysis by
inductively coupled plasma optical emission spectrometry
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3. Terminology
responsibility of the user of this standard to become familiar
with all hazards including those identified in the appropriate 3.1 Terms shall be defined in accordance with Terminology
Safety Data Sheet (SDS) for this product/material as provided B899.
by the manufacturer, to establish appropriate safety, health,
3.2 Definitions of Terms Specific to This Standard:
and environmental practices, and determine the applicability
3.2.1 cathodic protection, n—reduction of corrosion by
of regulatory limitations prior to use.
making the protected metal the cathode in a conducting
1.6 This international standard was developed in accor-
medium by applying direct current.
dance with internationally recognized principles on standard-
3.2.2 galvanic anode, n—a metal electrode that sacrificially
ization established in the Decision on Principles for the
corrodes when coupled to a more noble metal in a conducting
Development of International Standards, Guides and Recom-
medium, and thereby supplies a protective electric current to
mendations issued by the World Trade Organization Technical
the noble electrode.
Barriers to Trade (TBT) Committee.
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
This specification is under the jurisdiction of ASTM Committee B02 on Standards volume information, refer to the standard’s Document Summary page on
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee the ASTM website.
B02.04 on Zinc and Cadmium. Available from DLA Document Services, Building 4/D, 700 Robbins Ave.,
Current edition approved April 1, 2021. Published April 2021. Originally Philadelphia, PA 19111-5094, http://quicksearch.dla.mil.
approved in 1964. Last previous edition approved in 2016 as B418 – 16a. DOI: Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
10.1520/B0418-16AR21. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B418−16a (2021)
TABLE 2 Minimum Number of Anodes in Sample
3.2.3 saline electrolyte, n—a solution consisting of mainly
the chlorides of the alkali metals. Minimum Number of
Number of Anodes in Lot
Anodes in Sample
4. Ordering Information 1to500 2
500 to 1000 3
4.1 Orders for zinc anodes under this specification shall
Each additional 1000 or part thereof 1
include information as specified in Specification B949.
4.2 Additional ordering information specific to this standard
in a lot shall be thoroughly mixed to form a uniform sample of
is as follows:
not less than 50 g total.
4.2.1 Type of anode material (see Table 1),
6.1.3 Other sampling procedures shall be in compliance
4.2.2 Number of anodes,
with the provisions of Specification B949.
4.2.3 Size of anode and whether contains rod insert and if
so, type of insert and whether contains bolt hole and if so,
7. Methods of Chemical Analysis
whether threaded.
7.1 The chemical compositions enumerated in this specifi-
cation shall, in case of disagreement, preferably be determined
5. Chemical Requirements
by methods mutually agreed upon or the methods listed in
5.1 The anode shall be made from Special High Grade zinc
Table 3 (note: spectrochemical methods may include
conforming to Specification B6, with
...