軽金属
Online ISSN : 1880-8018
Print ISSN : 0451-5994
ISSN-L : 0451-5994
14 巻, 4 号
選択された号の論文の9件中1~9を表示しています
  • 田島 栄
    1964 年 14 巻 4 号 p. 223-225
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
  • 大日方 一司, 小松 登
    1964 年 14 巻 4 号 p. 226-230
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
    Molten aluminium is equilibrated with pure carbon over a temperature range of 800° to 1400°C under the pressure of 4×10-5mm Hg, and atmosphere. of argon Solubility of carbon in liquid aluminium under pres sure of 4×10-5mmHg is 0.10, 0.14, 0.16, and 0.32wt% at 800°, 1000°, 1100°, and 1200° respectively, and is high compared with the value obtained in the atmosphere of argon. The difference of solubility data was discussed as based on the existence of small amount of oxygen in the system. Solibility of carbon in solid aluminium is estimated to be 0.015wt% from the analytical data of graphite carbon.
  • 加熱ふん囲気中の水分に帰因するフクレ
    川島 浪夫, 山田 始, 横手 隆昌, 上野 紘
    1964 年 14 巻 4 号 p. 231-238
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
    The authors studied the effect of the dew point in the heating atmosphere and the effect of very small amounts of iron, silicon and beryllium added in super-purity aluminium on the blisters originating from the reaction of water vapour and aluminium. Further, the difference of electron diffraction patterns in two kinds of oxide film having the different effect on preventing the blisters and also the blistering rate at various heating temperature were studied.
    The results are as follows:
    (1) It is necessary to keep the dew point under about 5°C in air and about 10°C in nitrogen atmosphere in order to anneal 99.99% aluminium without blistering at 500°C.
    (2) Very small additions of iron and silicon to super-purity aluminium cause to increase the blisters. Although iron does not affect the blistering at the lower temperature such as 300°C, silicon causes slightly to increase the blistering.
    (3) Addition over 0.003% beryllium is proved to prevent the blistering completely.
    (4) The oxide film formed at higher temperature than 450-500°C in dry air distinctly affects to prevent the blistering. This oxide film showed the dotted diffraction ring whereas the oxide film formed at lower temperature (440°C) showing the perfect ring pattern has not the protective effect of blistering. In other words, the oxide film having a grown crystalline oxide by raising temperature, acts to prevent the blistering as compared with that having very small crystalline oxide formed at lower temperature.
    (5) There is a linear relation between the logarithm of blistering speed and the inverse of annealing absolute temperature.
  • αアルミナ皮膜生成機構の光学的解析
    田島 栄, 森健 実, 柴田 嘉基
    1964 年 14 巻 4 号 p. 239-244
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
    The authors found that α-alumina film is produced on aluminium by anodic oxidation in the low temperature melts of bisulphates.1, 2, 3) In this paper, in order to clarify the mechanism of formation, optical studies were made for such films as well as the films formed under certain other conditions which are likely to cause the thermal transition of amorphous alumina to crystalline structure. The films were then observed under polarized light and the existence of double refraction was checked. At the same time, refractive indices were determined for these films. The results were compared with those of X ray analysis.
    Main constituents of the films produced in sodium and potassium bisulphate melts or their mixtures were confirmed, optically too, to be α-Al2O3, The film formed in ammonium bisulphate melt contained an appreciable amount of γ-alumina. The films formed in conc. H2SO4 or in conc. H2SO4+oleum, consist mainly of γ-Al2O3, but by longer formation, it was partly converted to α-Al2O3. Even by aqueous ammonium borate solution, if anodic oxidation is continued for a long time under such high voltage at which sparking is noticed on the anode surface due to breakdown of the film, the film is gradually converted from amorphous, to γ-, and finally to α-Al2O3, though the transition may not be complete. From these experiments, it was confirmed that the local formation of α-Al2O3 by anodic oxidation of aluminium is not rare, though it is realized only by barrier type films and not by duplex (barrier plus porous) films.
    The thermal transition from amorphous, through γ-, to α-Al2O3, is caused by local heating of the anode surface due to remarkable exothermic reaction 2Al++++O--→Al2O3, Joule's heating effect through the film and by sparking.
    Further, when Al-Ti alloy is anodized in bisulphate melt, the film consists of α-Al2O3 and TiO2 in Anatase form (not in Rutile form).
  • 各種陽極化成皮膜の屈折率, 複屈折について
    田島 栄, 森 健実, 森田 典秀, 山尾 修平
    1964 年 14 巻 4 号 p. 245-252
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
    Optical observations facilitate the elucidation of the structure of anodic oxide films on aluminium which are mostly of amorphous nature and thus are difficult to be analyzed by X-ray diffraction.
    In the previous paper, the authors clarified the process of formation and the crystal structure of α-alumina films anodically formed in bisulphate melts by the use of optical means.
    In this paper, various anodic oxide films such as oxalic, sulphuric acid films formed at normal anodizing conditions and at lower temperature (hard-coating), chromic, sulphamic, phosphoric, boric (plus sulphuric) acid films, Ematal and Kalcolor films and boric acid-formamide films developed by the authors, were observed under polarizing microscopy and the refractive indices were determined and the existence of doubly-refracting properties was checked. Refractive indices of these films are usually lower than pure crystalline or amorphous alumina (1.67±1) and the films are composed mostly of amorphous alumina and including certain amounts of water and anions from the electrolyte. Formation at lower temperature and 'sealing' of the films lower the refractive indices.
    The anodic oxide films are very unstable (or active) when they are formed (as is seen from the commercial 'sealing' or 'dyeing' operations) and tend to transform into γ-Al(OH)3 (Gibbsite) by the stress produced during the growth of the films or by mechanical working applied externally, such as crushing or grinding. The phenomenon is notable in case of sulphuric acid films, especially of hard coating formed at lower temperature. The double refraction comes from the original properties of the compounds included in the films or from the porous structure of the film (form double refraction). The refractive indices of various films as compared with those of pure chemical substances are summarized in a chart. (Fig. 1)
  • Al-Si系合金におよぼすクロムの影響について
    久恒 中陽, 篠田 武雄
    1964 年 14 巻 4 号 p. 253-263
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
    1. Ternary diagram of Aluminium-Silicon-Chromium alloys.
    The diagram of Al-rich alloys containing silicon and chromium was investigated by means of thermal analysis, microscopic and X-ray examination. Al-rich corner up to 12% silicon and up to 4% chromium was studied. From several constitutional sections which have the same chromium-content respectively, the following conclusions were drawn: (1) In the range studied, the primary crystals are (Al), θ, η, α, β and Si. (2) The ternary refined compounds α and β are found to exist. (3) The non variant points are:
    Liq.+Al11Cr7_??_Al7Cr+α, at 647°,
    Liq.+Al7Cr_??_(Al)+α, at 630°,
    Liq.+α_??_(Al)+β, at 626° and
    Liq._??_(Al)+Si+β, at 576°.
    2. Effect of chromium on mechanical properties of Al-Si alloys.
    By adding of 0.3% chromium to the Al-Si alloys (5 to 12%Si), the micro-structure of sand casting and the mechanical properties are improved.
  • 市川 理衛, 斎藤 玲子
    1964 年 14 巻 4 号 p. 264-268
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
    The effect of intermetallic compounds on the hardness of magnesium alloys at the temperatures between room temperature and 450°C was investigated on binary alloys of Mg-Ag, Mg-Al, Mg-Bi, Mg-Ca, Mg-Cu, Mg-La, Mg-Ni, Mg-Sb, Mg-Si, Mg-Th, and Mg-Zn, containing various amount of the respetive alloying elements from a small amount up to the composition of the intermetallic compound. Hot strength of two phase alloys is thought to depend on the hot hardness of the matrix solid solution as well as that of the second phase including intermetallic compound. This was examined on binary magnesium alloys named above.
    The results obtained are as follows:
    1) Hot hardness-temperature relationships showed that the softening was displaced to higher temperature in the primary solid solution alloys containing La, Th and Ag than the alloys containing Al, Zn, Si and others.
    2) The definite inflection point on hardness-temperature curve was observed on some alloys at the composition of intermetallic compound and the point a was found to correspond to about 50-70% of the melting temperature (°K) of the compound.
    3) Most intermetallic compounds were found to be brittle at the temperature below the inflection point but were found to be plastic at the temperature above it. Higher inflection temperature was observed in Mg-La, Mg-Th and Mg-Ni compounds whereas lower inflection temperature was found in Mg-Zn and Mg-Ag compounds. On the compounds of Mg-Bi, Mg-Sb and Mg-Si no clear inflection point could be found, where hardness went down gradually by heating.
    4) Hardness of compounds at room temperature was found to be well correlated to the size factor of the alloying element against magnesium and the higher hardness was observed on the compound of the element with greater difference in atomic diameter from magnesium.
  • 放電孔明け加工条件と孔明け加工精度について
    財満 鎮雄, 平山 武, 加茂 進
    1964 年 14 巻 4 号 p. 269-274
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
    The electric discharge maching conditions of pure titanium plate are searched and the influences of the machining conditions for the drilling accuracy are discussed in this paper. The results are summarized as follows:
    1°The electric discharge drilling speed is affected by the source voltage, the source ampere and the condenser capacity, and, especially, the source voltage influences the drilling speed for good in their three, and if the three are increased at the same time, it may be seen their effects are distinctly.
    2°The machining ampere for the maximum machining speed is in about 25% value of source ampere and, if the source ampere increases, the most suitable machining ampere increases with it.
    3°The drilling accuracy becomes worse in saturation-curve like rising with the machining speed, and the accuracy is affected mainly by the sourse voltage and the condenser capacity. But the accuracy does not seem to be influenced by the machining ampere.
  • 小林 昌敏
    1964 年 14 巻 4 号 p. 275-283
    発行日: 1964/07/31
    公開日: 2008/10/30
    ジャーナル フリー
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