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The magnetic properties of amorphous Fe_(80)Si_xP_(20-x) alloys prepared by single roller quenching method have been investigated by Vibrating Sample Magnetometer and DC B-H loop tracer. The electrical properties and structure analysis have been studied by Electrical resistance measurement apparatus and X-ray diffractometer. The results are as follows; 1. The amorphous forming range of Fe_(80)Si_xP_(20-x) alloy s is 2≤x≤10, and the density increases linearly from 6.95 gr/cc at x=2 to 7.09 gr/cc at x=10 with increasing Si concentration. 2. The saturation magnetization and coercive force increase linearly from 152 gr/cc at x=2 to 168emu/gr at x=10 and from 0.29 Oe at x=2 to 7.37 oe at x=10 with increasing Si concentration, respectively. 3. The crystallization temperature and curie temperature increase from 695k at x=2 to 770K at x=10 and from 593k at x=2 to 643k at x=10 with increasing Si concentration, respectively. The crystallization temperature is about 100∼130K larger than curie temperature. 4. The electrical resistivity of amorphous state is from 150μΩ㎝ at x=2 to 155μΩ㎝ at x=10 with increasing Si concentration, and the amorphous state is about 40μΩ㎝ larger than that of crystallized state. 5. The temperature coefficient of resistivity for amorphous state is about 10 times larger than that of crystallized state, and increase linearly with increasing Si concentration.

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The effects of alloying elements on the solid solution hardening of molybdenum were investigated at 293-1073˚K. Specimens were prepared by are melting with 0.2 wt% Sc as a oxygen-scavenger and alloy additions were up to 1.5 wt% for V, Nb, Ti and 0.5 wt% for Zr. Vickers hardness was chosen as the measure of solution hardening. The results obtained were as following; 1. Atomic size difference between molybdenum and alloying element contributed significantly to the solution hardening. 2. Solution hardening, △H, was decreased with rising temperature, while solution hardening ratio, △H/H(Mo), increased with rising temperature. 3. The order of hardening effect was Zr$gt;Ti$gt;Nb$gt;V, however, at the higher temperature from 873˚K, the effect would be some what reversed such that the effect of V was larger than that of Ti and Nb.

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The extraction of alumina as a chloride from the calcined clay was about 91% when leached with a 20 w/o HCl solutions for two hours. Alumina extraction from the uncalcined clay was 80% when leached with 20 w/o HCl at 110℃ for 4½ hrs. It was found that the leaching rate was influenced by temperature, acid concentration, and not by particle sizes. From the temperature dependence of the leaching rate, the activation energy was determined to be 7.7 Kcal/㏖. The impurity in pregnant solution, Fe, was removed to the degree of 91% using the solvent extraction technique under the condition of 30 v/o-TBP and O/A=1.

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The properties of Fe-Sn sintered compact for porous bearing and the phenomena appearing in heating process of Fe-1.0 Sn mixed powder compacts were investigated in comparsion with those of Fe powder compact, The results obtained are as follows. 1. When Fe-1.0 Sn mixed powder compact is sintered at temperatures above about 1000℃, the dimensional change and intercommunicating porosity are almost same with those of Fe compact, but the radial crushing strength is higher than that of Fe compact. 2. When Fe-1.0 Sn mixed powder compact is heated the liquid tin which formed at its melting point penetrates into capiliaries of Fe skeleton at temperatures above about 350℃. And with the rising temperature up to about 900℃, the Sn liquid react with Fe powder to form various Fe-Sn intermetallic compounds; θ, η, E and ζ. But at temperature above about 1000℃, all the intermetallic compounds became to a phase of Fe-Sn solid-solution having a higher self-diffusion coefficient than that of the γ phase. As a result Fe-1.0 Sn compact have a higher strength and more shrinkage ratio than Fe compact when sintered at temperatures above about 1000℃, which is usually employed in the case of sintering of Fe base compacts.

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Electrical conductivity measurement was made on synthetic wustite which was respectively doped with Li₂O, CaO, Al₂O₃ and SiO₂ in the temperature range of 20℃ to 1000℃. The A.C. conductivity of the wustite was measured by means of the two prove method. Their electrical conduction were found to be characterized by a typical semiconductor behavior. A plot of logarithm of conductivity versus reciprocal temperature was fairly linear, and the activation energy calculated was approximately 0.12 eV below about 600℃, whereas above that temperature, 0.042 eV. Electrical conductivity of the wustite was increased by adding Li₂O or CaO and decreased by adding Al₂O₃ or SiO₂ into wustite. This behavior could be explained in terms of lattice defect It was also found that the electrical conductivity of wustite was practically proportional to concentration of electron hole i.e. Fe＾(+3) ion in the lattice.

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The basic precesses for fabricating Sm(Co, Fe, Cu, Zr)_z permanent magnets consist of alloy melting, powder comminution, powder compacting in magnetic field, sintering compacts, solution-and aging treatment of the sintered products. The present study was undertaken primarily to investigate effects on magnetic properties of Sm(Co, Fe, Cu, Zr)_z magnets of compositional varialbes (Co, Fe, Cu, Zr and atomic ratio z), solution-treatment and step-aging treatment conditions. Magnetic properties of (BH)_(max) of 25.2 MGOe, B_r of 10.85 KG and _bH_c of 9 KOe were achieved by sintering compacts of Sm(Co_(0.639)Fe_(0.275)Cu_(0.069)Zr_(0.017))7.28 at 1190℃ for 1 hour, solution treatment at 1150℃ for 3 hours and step-aging treatment holding at 875℃ for 10 hours, cooling to 400℃ in 12 hours and holding at 400℃ for 10 hours.

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