Two kinds of dumet wires (copper clad Fe-Ni alloy wires) with thick and thin copper oxide layer, were sealed into an alkali barium silica glass by heating moderately and excessively, respectively. Concentration distribution of elements along radial direction was measured by an electron probe microanalyzer.
The results were as follows:
1) The distance of diffusion front of copper from the surface of the wire was about 70μ and 30 to 40μ for excessively and moderately heated seal, respectively.
2) Barium showed peculiar distribution. Maximum and minimum points were formed at about 5 and 10μ distance from the surface of wire, respectively. The extremums were distinct in excessively heated seals.
3) Sodium and potassium showed flat distribution in glass except high concentration at copper-glass interfaces.
4) In moderately heated seals, copper oxide partly disolved into glass. The remainder seemed to behave as bridging layer between copper and copper-containing glass.
In Excessively heated seals, most of copper oxide diffused into glass. Very thin layer, however, was presumed to remain behaving as bridging layer between copper and copper-containing glass.

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オープンサイクルMHD発電チャンネル用長寿命絶縁壁を開発しこの特性を調べた. この絶縁壁はBeO磁器の素子を用いて構成し, これを熱入力1.2MW材料試験機によって, 耐熱衝撃試験, 腐蝕試験及び通電耐久試験を実施することによって, 絶縁壁構造と安全使用条件を検討した. この結果, 180W/cm²以下の燃焼ガスプラズマによる熱負荷条件ではコールド壁方式として優れた絶縁壁構成が可能であることを示した.

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Magnesia powders, which were obtained by calcination of synthetic magnesium hydroxide (99.9wt% MgO ignited basis) at the temperature range of 500 to 900°C, were hot pressed at 250kg/cm² in air. The pressure was applied at room temperature and maintained while the temperature was raised at a rate of 200°C/h up to 900°C. The shrinkage and the crystallite size of the powder compacts during hot-pressing were measured.
The results obtained were summarized as follows:
(1) In the hot-pressing of magnesia powders calcined at the temperatures lower than 800°C, the rapid shrinkage was observed at the temperatures below 700°C.
(2) The lower the calcination temperature of magnesium hydroxide, the lower the temperatures at which the rapid shrinkage took place.
(3) The rapid crystallite growth of magnesia was observed during the rapid shrinkage.

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ホットプレス緻密化の全領域において連続した一定形状の開気孔が一定方向に配向したニュートニアン固体からなる単一系および, その単一系中に骨材繊維が同一方向に配向する複合系の各緻密化理論式 (Eq. (2) およびEq. (4)) を誘導した. 各理論式の妥当性を, 実際に, 単一系に対しては径の揃ったガラス繊維を配向充填させ, また複合系に対してはガラス繊維の配向充填体中にこれと濡れ性が異なる各種骨材繊維を分散配向させた系を用いて実験的に検討した. 特に実験では, 表面張力および界面張力が緻密化速度におよぼす影響を検出しやすくする目的で通常のホットプレス法で採用される外圧に比較して極めて低い圧力下で行った.

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酸化アルミニウムと炭酸マグネシウムからアルミン酸マグネシウムを生成する反応の初期段階での種々弗化物添加の影響を研究した. アルカリ金属の弗化物を添加するとLiF>NaF>KF>RbF>CsFの順序にアルミン酸マグネシウムの生成反応を促進する. またアルカリ土類金属の弗化物を添加すると, MgF₂>CaF₂<SrF₂<BaF₂の順に反応促進効果が認められた. これらの反応過程で弗素は酸化アルミニウムのみならず酸化マグネシウムにも同時に作用し, アルミン酸マグネシウムの生成は弗化物と酸化アルミニウム, 酸化マグネシウムの三成分が同時に相互作用する状態をへて生成すると推定した. この結果にもとづいて, 三成分の相互作用状態を活性化状態として含むアルミン酸マグネシウムの生成機構としてつぎのような反応機構を提出した.
MgO+Al₂O₃+2MF(M'F₂)=[Al₂-O₃↑F-M↓Mg-O]=MgF₂+M₂Al₂O₄(M'Al₂O₄)=MgAl₂O₄+2MF(M'F₂)
その結果, 反応MgO+Al₂O₃+2MF(M'F₂)=MgF₂+M₂Al₂O₄(M'Al₂O₄) のエンタルピー変化を添加剤弗化物の反応促進効果の目やすとして用いることができ, エンタルピー変化の小さいものほど促進効果が大きい. これによりアルカリ, アルカリ土類金属弗化物による促進効果の順序を説明できる. 最後にコバルト, ニッケル, 亜鉛の弗化物添加の影響について議論した.

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This study was concerned with the formation and color development of the spinel solid solution in CoO-ZnO-Cr₂O₃-TiO₂-SnO₂ system, and its application to colored glazes.
Specimens were prepared by calcining the oxide mixture at 1400°C for 1hr. The formation of spinel solid solution was examined by X-ray diffraction, the color was discussed by measuring the spectral reflectance, and the stability of the spinel in glazes was tested.
The results were summarized as follows.
1) Formation of a continuous solid solution was confirmed by X-ray analysis.
2) As the amount of Cr³⁺ increased in ZnO-Cr₂O₃-SnO₂ system, the color changed from white through grayish olive green to grayish leaf, and the absorption of Cr³⁺ shifted towards violet region.
3) An increase of Cr³⁺ in ZnO-Cr₂O₃-TiO₂ system caused the color to change from white through leaf to grayish leaf, and the absorption of Cr³⁺ shifted towards violet region.
4) The color obtained in ZnO-Cr₂O₃-TiO₂-SnO₂ system ranged from leaf to yellowish green.
5) An increase of Cr³⁺ in CoO-ZnO-Cr₂O₃-SnO₂ system yielded the colors ranging from grayish leaf through grayish olive green to strong blue green, and the absorption of Cr³⁺ shifted towards violet region.
6) As the amount of Cr³⁺ increased in CoO-ZnO-Cr₂O₃-TiO₂ system, the colors ranging from dark yellow through olive to strong blue green developed, and the absorptions of Co²⁺ and Cr³⁺ shifted towards violet region.
7) As the amount of Ti⁴⁺ increased in CoO-ZnO-TiO₂-SnO₂ system, the color changed from grayish leaf through grayish yellow to dark yellow, and the absorption of Co²⁺ shifted towards red region.
8) The colors ranging from leaf to olive developed in CoO-ZnO-Cr₂O₃-TiO₂-SnO₂ system.
9) According to the result of the colored glaze test, formation of a new spinel was observed, and the specimens with the composition of Cr³⁺ rich region were stable as a glaze stain.

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The effect of Nb₂O₅ additive on the sintering of SnO₂ was investigated by measuring density, shrinkage and grain size in the temperature range 1200 to 1400°C in O₂, air and N₂. The sinterability of SnO₂ compacts was increased with Nb₂O₅ content, and at a concentration of 5wt% Nb₂O₅, high-density bodies of 95% of theoretical were obtained after sintering at 1400°C for 10hr in O₂. From electrical resistivity and X-ray diffraction data, it might be consideredthat niobium ion was soluble in SnO₂ up to about 3wt%. Electron microscopic observation of polished specimens showed that Nb₂O₅ second-phase particles inhibited the grain growth and grain growth kinetics could be described by D=kt^m; the values of time exponent “m” were found to be 1/4 and 1/6 for the specimens with Nb₂O₅ content of 3wt% and 5wt%, respectively.
In the initial stage of the sintering, relatively fast shrinkage occurred by addition of Nb₂O₅ without formation of liquid phase, and then Nb₂O₅ second-phase particles decreased the grain growth rate which dominated the sintering kinetics during the later stage.

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保有容量200kg級の単一槽炉にて膨脹係数32-35×10^-7(cm/cm/℃) 級の珪酸硼ガラスのフレネルレンズ等を製造しつつ電気熔融実施に際しての基本的資料 (ガラスの分光透過特性, 電気抵抗特性, 熔融効率, Mo-電極溶出測定等) を求めた. この結果を参考とし, かつ外挿によって, 保有量0.2-8.5t級の小型電気熔融炉設計について若干の考察をおこなった.

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