ASTM E1257-93(1998)e1

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
e1
Designation: E 1257 – 93 (Reapproved 1998)
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 (e) indicates an editorial change since the last revision or reapproval.
e NOTE—Footnote 1 was corrected in October 1998.
1. Scope 5. Evaluation of Grinding Materials by Direct Analysis
1.1 This guide gives recommendations for the evaluation of 5.1 Table 1 shows an example of semiquantitative spectro-
various grinding materials used to prepare the surfaces of graphic analysis of various grinding belts from different
specimens to be analyzed by optical emission or X-ray producers. An examination of these analyses identifies the
emission spectroscopy. elements most likely to contaminate the surface of the speci-
1.2 This standard does not purport to address all of the men. The more critical the element and the lower its concen-
safety problems, if any, associated with its use. It is the tration in the specimen, the more important are low-level
responsibility of the user of this standard to establish appro- concentrations in the belts.
priate safety and health practices and determine the applica- 5.1.1 For example, using the 80-grit zircon belt in the
bility of regulatory limitations prior to use. determination of 0.5 % chromium, the trace level of chromium
in the belt should cause no problem, but in the determination of
2. Referenced Documents
0.02 % aluminum, that belt probably will cause a problem. In
2.1 ASTM Standards:
the determination of calcium at ppm levels in steel, even low
E 135 Terminology Relating to Analytical Chemistry for levels of calcium in the belts cause problems.
Metals, Ores, and Related Materials
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
3. Terminology
these analyses. Major components in the belts will cause
3.1 For definitions of terms used in this guide, refer to
greater problems in the determination of these elements.
Terminology E 135.
5.2.1 Direct analysis of the grinding material is particularly
useful in such analyses as the determination of calcium in steel,
4. Significance and Use
where the analyte is generally too inhomogeneous to use the
4.1 The grinding materials used for the preparation of the
methods described in Section 6. This analysis requires a
surfaces of specimens prior to analysis by optical emission or
virtually calcium-free belt as in Fig. 2.
X-ray emission spectroscopy can contaminate the surface and
6. Evaluation of Grinding Materials by Specimen
thus produce erroneous results. This guide provides examples
Examination
of the effects of these contaminations and recommendations for
evaluating grinding materials to eliminate or reduce these
6.1 The effect of grinding materials depends on the analyti-
effects in spectrochemical analysis.
cal method. In optical emission analysis, the preburn will, in
4.2 The examples given in this guide are not the only
general, volatilize the grinding material left on or driven into
contaminations which can occur. Especially in X-ray spectrom-
the surface (see 6.3). For X-ray emission analysis, the material
etry, all phases of the surface preparation should be examined
left on the surface will be analyzed as being specimen material.
for potential contamination effects.
6.2 Table 2 shows X-ray emission analyses of a steel
4.3 Analytical significance of the contaminations observed
specimen after surfacing with various grinding materials. By
depends on the needs of the analyst for the particular applica-
tabulating the results in this manner, it becomes obvious what
tion at a given concentration level.
problems are occurring from the various grinding materials.
Where there is no change from material to material, beyond the
precision of the method of analysis and the homogeneity of the
This guide is under the jurisdiction of ASTM Committee E-1 on Analytical
material, no contamination has occurred. But where the con-
Chemistry for Metals, Ores and Related Materials and is the direct responsibility of
Subcommittee E01.20 on Fundamental Practices and Measurement Traceability.
centration of a given element appears higher, there has been
Current edition approved Jan. 15, 1993. Published March 1993. Originally
contamination. Such is the case with the determination of
published as E 1257 – 88. Last previous edition E 1257 – 88.
2 silicon using the silicon carbide belt and the bonded diamond
Annual Book of ASTM Standards, Vol 03.05.
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NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
e1
E 1257 – 93 (1998)
TABLE 1 Semiquantitative (Spectrographic) Analysis of Grinding Belt Abrasives
80-Grit Silicon Carbide 80-Grit Alumina
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 Si
...