emission spectrometry to measure the compositions of iron and steel at differ- ent levels when the size of the samples were sufficiently large; semi-quantitative X-ray microanalysis (XRM) in combina- tion with scanning electron microscopy (SEM) to characterize the composition of small liquid metal drops; and Moss- bauer spectroscopy and X-ray diffraction analyses to identify compounds in the oxide layer of the metallic materials. Carbon, sulfur, volatile and ash con-
tent in coke samples were determined by proximate analyses, and X-ray diffraction was used to determine the variations in the degree of crystallization of coke as it descended through the cupola. Samples of 98% and 36% SiC were
crushed and analyzed for carbon and sulfur by LECO analyses. X-Ray fluo- rescence analyses were used to determine all other elements. X-Ray diffraction was used to determine the presence of crystalline phases.
quenched cupola experiments, i.e., the rapid mixing of the layers of coke and metal that are initially charged, the oxida- tion of steel and the decreasing size of coke with descent in the cupola. Figure 2 provides views of the charge materials at different levels in the cupola. Samples of the different materials
3
important in the cupola performance, including cast iron, steel, silicon carbide and coke, were collected and analyzed by different techniques. Figure 3 shows a sil- icon carbide sample observed using SEM in combination with semi-quantitative X-ray microanalysis to characterize the composition of the phases. Subsequent papers report the results of these char- acterizations. Figure 4 and Table 2 show the examination of high sulfur regions on the steel surface. Coke samples taken from each level provided evidence of melting performance (Fig. 5). Te researchers determined the best
measure of whether the experimental results represent the same basic processes that take place in commercial cupolas to be a comparison of cupola output data with the computer simulation program’s predictions. Te computer simulation
44 | MODERN CASTING August 2013 Figure 3. The surface of lump SiC shows a reaction zone between the SiC and the slag covering.
Results and Conclusions Te visual observations of
the materials inside the cupola were qualitatively the same as the observations made in earlier
Figure 2. These views depict the charge materials at different levels.
Figure 4. Shown are semiquantitative analyses of a sulfur-bearing phase on the steel surface.
Table 2. Semiquantitative Chemical Composition (EDX) of a Sulfur-bearing Phase on the Steel Surface (Spectrum 1 of Fig. 4)
ELEMENT %WEIGHT
C 15.25 O 14.92 S 10.76 Fe 59.07
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