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The extraction of zirconium(VI) from an aqueous solution of constant ionic strength with versatic acid - 10 dissolved in benzene was studied as a function of pH and the concentration of zirconium(VI) and organic acid. The effects of sulphate and chlorine ions on the extraction of the zirconium(VI) ware briefly examined. It was revealed that (ZrOR₂.2RH) is the predominant species of extracted zirconium(VI) in the versatic acid - 10. The chemical equation and the apparent equilibrium constants thereof have been determined as follows. (ZrO^(2+))aq＋2(R₂H₂)_(org) = (ZrOR₂.2RH)_(org)＋2(H^+)_(aq) Kzr = (ZrOR₂.2RH)_(org)·(H^+)²/(ZrO^(2+))_(aq)·(R₂H₂)²_(org)＝3.3×10^(-7) The synergistic effects of TBP and D2EHPA were also studied. In the mixed solvent with 0.1M TBP, the synergistic effect was observed, while the mixed solvent with D2EHPA showed the anti-synergistic effect.

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To determine the mechanism by which zinc ferrite forms when ferrous zinc sulphide ore is roasted, the experiment has been carried out under given conditions by sufficiently mixing zinc oxide with ferric oxide in a stoichiometric way. The results obtained from this experiment are summarized as follows: 1) Formation of zinc ferrite was confirmed by x-ray diffraction analysis in formed compound at alternation of various mole ratio and temperatures. 2) Zinc ferrite was obtained by stoichiometric ratio without any effect of mixed mole ratio i.e., zinc ferrite was not confirmed at temperature less than 700℃, but was found at above 700℃. 3) Zinc leaching rate of synthetic zinc ferrite on sulphuric acid solution or ammonium salt solution was similar at low temperatures (below 680℃), but decreased at above 700℃. For ammonium salt solution (ZnO: Fe₂O₃＝1 : 1), the zinc leaching rate was found to be 9.07% at 1000℃ and 49.97% at 700℃, respectively. This zinc leaching rate for sulphuric solid solution (ZnO: Fe₂O₃＝1 : 1), however, showed 25.03% at 1000℃ and 95.79% at a temperature 700℃. Therefore, zinc leaching rate of zinc ferrite on sulphuric acid solution was found to be more than twice as much as for ammonium salt solution. 4) Zinc ferrite was found to from at 1000℃ even under conditions of changing mole ratio. For ZnO: Fe₂O₃= 1:1, however, the formation of zinc ferrite only was confirmed. When values of the ratio of ZnO to Fe₂O₃were 1 to 1 and 5 to 1, both zinc ferrite and free zinc oxide were obtained, where when its value was 1 to 2 the formation of zinc ferrite and free Fe₂O₃was determined.

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Liquids-α two phase region of W-Ni-Fe system at 1540℃ has been calculated thermodynamically from ternary regular solution model of Meijering, Kaufman and Bernstein. The results have been compared with the experimental liquidus line and the solidus line calculated from experimental liquidus data and two equations of ternary equilibrium conditions. The deviation between the calculated and the experimental liquidus lines becomes greater as the Fe/Ni ratio increases, which is expected to be resulted from the simplified ternary regular solution model. The two solidus lines show relatively good agreement, especially when Fe/Ni ratio is low.

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Textures of new high permeability boron-silicon-iron alloys at the stage of cold worked, primary and secondary recrystallization have been investigated as a function of the final cold work in a two stage reduction method by analysis of inverse pole figure. Texture at primary recrystallized stage as well as cold worked stage consists of (222), (211) and (200) components, and the intensity of the texture increases with an increasing final cold reduction. Secondary recrystallized texture consists of (110), (222), and (211) components, and the intensity of the (110) component increases sharply with increasing the final cold reduction indicating that a texture induced inhibition, in addition to solute inhibition, plays an important role in the secondary recrystallization in boron-silicon-steels. Metallographic analysis shows that the heavier the final cold reduction the fewer the secondary nuclei and the larger the secondary grain.

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A general equation was derived for the rate of reaction of a porous solid with liquid reactant. Spherical porous are assumed to be distributed uniformly within the spherical particle. The equation takes into consideration the intrinsic rate constant, intra-particle diffusion, and the specific surface area of pores, which increases as the reaction progresses. For the highly porous solid, the general equation holds until the pores overlap and sub-grains form within the particle.

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Tempering behavior of very low carbon (about 0.01%) Fe-Ni martensitic alloys was studied. For this purpose, two Fe-Ni alloys having different martensite substructures were prepared: one was Fe-18% Ni alloy of lath martensite and the other was Fe-31.7% Ni alloy of plate martensite plus small amount of retained austenite. Optical microstructures and transmission electron micrographs were observed to identify any carbide precipitation and substructural changes during tempering. Hardness and tension tests were performed and the mechanical property change with tempering was discussed.

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