ASTM E634-05

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:E634–05
Standard Practice for
Sampling of Zinc and Zinc Alloys for Optical Emission
1
Spectrometric Analysis
This standard is issued under the fixed designation E634; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ceramic or graphite ladle, as the solubility of iron in Special High Grade
1. Scope
Zinc is sufficient to cause a measurable contamination.
1.1 Thispracticecoversthesamplingofzincandzincalloys
4.2 Sample Molds, designed to produce homogeneous chill-
to obtain a sample suitable for quantitative optical emission
cast specimens having smooth surfaces, free from surface
spectrochemical analysis. Included are procedures for obtain-
pockets and pores. The specimens shall be representative (in
ing representative samples from molten metal, from fabricated
the region to be excited) of the product metal. The samples
or cast products that can be melted, and from other forms that
shall have a spectrochemical response similar to the standards
cannot be melted.
used in preparing the analytical curves. This is ensured by
1.2 The values stated in SI units are to be regarded as
casting standards and specimens in the same manner.Also, the
standard. The values given in parentheses are for information
specimens shall have a repeatability of measurement for major
only.
elements from excitation-to-excitation with a relative error of
1.3 This standard does not purport to address all of the
no more than 2%. Several types of molds have been found
safety concerns, if any, associated with its use. It is the
acceptable.
responsibility of the user of this standard to establish appro-
4.2.1 Type A, Pin Mold (Fig. 1)—This mold produces two
priate safety and health practices and determine the applica-
diagonally cast pins with sprues at the top of the specimens.
bility of regulatory limitations prior to use.
The mold dimensions are such as to produce pins approxi-
2. Summary of Practice
mately 100 mm (3.9 in.) in length by 11 mm (0.4 in.) in
diameter. The mold is made of steel or cast iron and weighs
2.1 Molten metal representative of the furnace melt is
approximately 4.5 to 5.5 kg (10 to 12 lb). Pin specimens have
pouredintoamoldtoproduceachill-castsample.Thesample,
been found to be very homogeneous. If properly prepared,
which must represent the average composition, is machined to
these specimens provide very reliable results with only one
a specified shape to produce an acceptable surface for excita-
burn. However, pin specimens must be reshaped for each
tion.
additional burn.
2.2 Fabricated or cast products are remelted and cast into
4.2.2 Type B, Book Mold (Fig. 2)—This mold produces a
molds or are excited directly without remelting.
vertically cast disk with a sprue on the edge of the specimen.
3. Significance and Use
The mold dimensions are such as to produce a disk of
approximately 64 mm (2.5 in.) in diameter by 6 to 8 mm (0.2
3.1 This practice, used in conjunction with an appropriate
to 0.3 in.) in thickness.Acircular central recess, 15 to 25 mm
quantitative optical emission spectrochemical method, is suit-
(0.6 to 1.0 in.) in diameter, on one side of the specimen
able for use in manufacturing control, material or product
facilitates machining of that side in preparation for excitation.
acceptance, and development and research.
Italsopromotesmoreuniformfreezingoftheraisedperipheral
4. Apparatus
area. The mold is made of steel or cast iron and weighs
approximately 2 to 3 kg (4 to 7 lb). This mold works well for
4.1 Ladle, of steel, designed to hold sufficient molten metal
to completely fill the sample mold, with a handle of sufficient high purity zinc grades, but with alloys may cause segregation
due to solidification phenomena. Specimens should be excited
length to reach into a furnace, trough, pot, or crucible.
onlyintheareasindicatedinFig.3,anditmaybenecessaryto
NOTE 1—Pure zinc metal (Special High Grade) is sampled using a
make several burns and report an average.The user is strongly
cautioned to thoroughly investigate specimen homogeneity for
1
This practice is under the jurisdiction ofASTM Committee E01 onAnalytical each alloy system to be analyzed.
ChemistryforMetals,Ores,andRelatedMaterialsandisthedirectresponsibilityof
4.2.3 Type C, Center Pour Mold (Fig. 4)—This mold
Subcommittee E01.05 on Cu, Pb, Zn, Cd, Sn, Be, theirAlloys, and Related Metals.
produces a horizontally cast disk with a sprue over the center
Current edition approved Oct. 1, 2005. Published November 2005. Originally
on the back side. The mold dimensions are such as to produce
approved in 1978. Last previous edition approved in 2001
...