ASTM E1257-93(2008)

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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
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Designation:E1257–93 (Reapproved 2003) Designation:E1257–93 (Reapproved 2008)
Standard Guide for
Evaluating Grinding Materials Used for Surface Preparation
in Spectrochemical Analysis
This standard is issued under the fixed designation E 1257; 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
1.1 This guide covers recommendations for the evaluation of various grinding materials used to prepare the surfaces of
specimens to be analyzed by optical emission or X-ray emission spectroscopy.
1.2 This standard does not purport to address all of the safety problems, 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.
2. Referenced Documents
2.1 ASTM Standards:
E 135 Terminology Relating to Analytical Chemistry for Metals, Ores, and Related Materials
3. Terminology
3.1 For definitions of terms used in this guide, refer to Terminology E 135.
4. Significance and Use
4.1 The grinding materials used for the preparation of the surfaces of specimens prior to analysis by optical emission or X-ray
emission spectroscopy can contaminate the surface and thus produce erroneous results.This guide provides examples of the effects
of these contaminations and recommendations for evaluating grinding materials to eliminate or reduce these effects in
spectrochemical analysis.
4.2 The examples given in this guide are not the only contaminations which can occur. Especially in X-ray spectrometry, all
phases of the surface preparation should be examined for potential contamination effects.
4.3 Analytical significance of the contaminations observed depends on the needs of the analyst for the particular application at
a given concentration level.
5. Evaluation of Grinding Materials by Direct Analysis
5.1 Table 1 shows an example of semiquantitative spectrographic analysis of various grinding belts from different producers.
An examination of these analyses identifies the elements most likely to contaminate the surface of the specimen. The more critical
the element and the lower its concentration in the specimen, the more important are low-level concentrations in the belts.
5.1.1 For example, using the 80-grit zircon belt in the determination of 0.5 % chromium, the trace level of chromium in the belt
should cause no problem, but in the determination of 0.02 % aluminum, that belt probably will cause a problem. In the
determination of calcium at ppm levels in steel, even low levels of calcium in the belts cause problems.
5.2 Figs. 1-6 show energy dispersive X-ray analyses of various belts and the same logic applied in 5.1 can be used with these
analyses. Major components in the belts will cause greater problems in the determination of these elements.
5.2.1 Direct analysis of the grinding material is particularly useful in such analyses as the determination of calcium in steel,
where the analyte is generally too inhomogeneous to use the methods described in Section 6. This analysis requires a virtually
calcium-free belt as in Fig. 2.
6. Evaluation of Grinding Materials by Specimen Examination
6.1 The effect of grinding materials depends on the analytical method. In optical emission analysis, the preburn will, in general,
This guide is under the jurisdiction of ASTM Committee E01 on Analytical Chemistry for Metals, Ores and Related Materials and is the direct responsibility of
Subcommittee E01.20 on Fundamental Practices and Measurement Traceability . Practices.
Current edition approved June 10, 2003.May 1, 2008. Published July 2003.June 2008. Originally approved in 1988. Last previous edition approved in 2003 as
´1
E1257–93(1998) .E 1257 – 93 (2003).
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. For Annual Book ofASTM Standards
, Vol 03.05.volume information, refer to the standard’s Document Summary page on the ASTM website.
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E1257–93 (2008)
TABLE 1 Semiquantitative (Spectrographic) Analysis of Grinding Belt Abrasives
80-Grit Silicon Carbide 80-GritAlumina
Concentration,% 80-Grit Zircon
No. 1 No. 2 No. 3 No. 1 No. 2 No. 3
10+ Si Si Si Al Al, Ca Al Al, Ca, Zr
1–10 Ca Ca Ti Si, Na, Fe
0.1–1 Ba, Mg Fe,Al, Na Mg, Si, Ca, Ti Fe, Si, Na Ca Ti, Zn
0.05–0.5 B Fe, B Mg
0.01–0.1 Mn, Na B, Mg Al Ba, B Zr Na Mg
0.005–0.05 V, Cu, Ti, Ni Mn, Ti V, Ca, Na, Ni Mn, Zr, Cu, Na B B, Fe, Si B, Mn, Sr
Trace–0.01 Mo, Zr, Sr Ba, V, Zr, Cu, Ba, Mn, Mg, Pb, Cr, Ni Ba, Mn, Cr, V, Mn, Mo, Cu, Ba, Pb, Cr, V,
Ni, Sr Zr, Cu, Ti, Sr Cu, Ni, Sr Sr, Mg Mo, Cu
FIG. 1 EDX Analysis of Silicon Carbide Grinding Belt, 60-Grit
FIG. 2 EDX Analysis of Silicon Carbide Grinding Belt, 240-Grit
volatilize the grinding material left on or driven into the surface (see 6.3). For X-ray emission analysis, the material left on the
surface will be analyzed as being specimen material.
6.2 Table 2 shows X-ray emission analyses of a steel specimen after surfacing with various
...