By X-ray diffraction method, quantitative analisis on quartz and feldspar in natural silica sands were examined. There were many investigations on quantitative determination of quartz by this method, but few on the feldspars because of the complexity of the constituents and structures. However, by means selecting X-ray diffraction condition and measuring X-ray intensity adequately, the authors could obtain good results, and then these were compared with the results measured by staining method and chemical analysis. The results obtained were as follows:
  1. The fairly accurate calibration curves of X-ray intensity versus contents of quartz, microcline, albite, oligociase, and andesine were obtained.
  2. The contents of quartz and feldspars in silica sands which were measured by X-ray diffraction method agreed quantitatively with the results of the staining method and chemical analysis.
  3. These quantitative methods have characteristic merits respectively, so one or two methods of them must be selected according to the purpose.

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  Some studies on the wear mechanism of cast iron were already reported and it is generally supposed thet at lower sliding speed the oxidation wear, at slightly higher speed than that the abrasive wear and more higher speed the seizure occur. However a few questionable points were still remained.
  In this work the wear phenomena of cast iron under no-lubricated sliding were examined by X-ray analysis of wear particles and sliding surface of the specimens. Results obtained were summerized as follows.
  1. At lower sliding speed, the wear particles are easily oxidized to Fe₂O₃ and the wear loss is very small. This stage may be called the first oxidation range.
  2. At slightly higher speed, about 0.5∼1.5 m/s, the abrasive wear occurs and the wear loss increases very much. This is generally named the critical speed of wear of cast iron, at which the wear debris is αFe itself.
  3. In the early stage of wear at higher speed than the critical one, the wear particles transform to martensite and retained austenite.
  4. However, the wear particles are oxidized as the stationary wear continues. The oxide changes from Fe₂O₃ to Fe₃O₄, and what is more, to FeO with increasing of sliding speed or sliding distance. This stage may be called the second oxidation wear range.

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  It is important in cupola operation to solve the lining erosion mechanism.
  The authors studied the erosion resistance and the change of chemical composition and mineral materials in the erosion zone. Using neutromelt ganister for the cupola lining materials, it is expected that a similar formation of new mineral materials would occur as is produced by the reaction between molten iron and slag on a clay bond graphite crucible.
  The following results were obtained :
  1. Neutromelt ganister is manufacured by a special method whereby silica material is coated with graphite.
The grain size distribution was found to contain two peaks at about 0.1-0.5mm dia. and 2-3mm dia.
  2. The reaction between molten iron and slag created an alteration zone. This zone had a very stable erosion resistance against acid slag but not so good against basic slag.
  3. This zone was very thin about 1-2mm thick and a large number of SiC particles were present unusually.
  4. The other zone was very weakly sintered, but such defects as a) peel back b) cracks perpendicular to the surface and c) spalling were not observed in this zone.

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