巻号一覧
後続誌
56 巻, 6 号
選択された号の論文の6件中1～6を表示しています
- |<
- <
- 1
- >
- >|
研究論文
-
林 守宏, 杉村 誠一, 伊藤 喜憲, 大平 五郎, 横田 理1984 年 56 巻 6 号 p. 321-328
発行日: 1984/06/25
公開日: 2011/11/26
ジャーナル フリーInvestigation of abnormal image appearance in radiographic films and the analysis of its cause have been performed with test pieces of coarse grain sizes cut from a continuously cast billet of austenitic stainless steel. The image is a long, narrow and stripped pattern in horizontally cut test piece and squamouse pattern in vertically cut test pieces, although the pattern of the macrostructure were identical. It has been experimentally verified that this abnormal image is caused mainly by X-ray diffraction which occurs when X-ray penetrates the solidified structure in the test piece and is not due to any segregation of chemical compositions; and further that the precipitated δ-ferrite is the factor that affects the contrast of the abnormal image.抄録全体を表示PDF形式でダウンロード (894K) -
糸藤 春喜, 川野 豊, 井ノ山 直哉, 西 正1984 年 56 巻 6 号 p. 329-336
発行日: 1984/06/25
公開日: 2011/11/26
ジャーナル フリーThe formation process and substructure of compacted/vermicular (C/V) graphite in cast irons were studied by means of optical, scanning and transmission electron microscopies. It was found that only spherular graphite crystallized in the early stage of solidification as the primary form of C/V graphite. The growth of C/V graphite started during the middle of eutectic solidification. Spherular graphite was observed in most eutectic austenite shells during the eutectic growth and was connected with C/V graphite. The C/V graphite during the growth was in contact with the melt through the filmy melt channels and then grew along the channels. It was observed that C/V graphite was constructed with the graphite tips and the dominant growth direction was along the a-axis of the hexagonal graphite structure, although they appeared to grow along the c-axis. It was considered that the form and substructure of graphite in cast irons depended on the site where graphite crystallized.抄録全体を表示PDF形式でダウンロード (876K) -
久保 公雄, 笠原 愛一, 福迫 達一1984 年 56 巻 6 号 p. 337-343
発行日: 1984/06/25
公開日: 2011/11/26
ジャーナル フリーApparent thermal conductivity independent of mold temperature and thermal conductivity as a function of mold temperature were determined from experimental data obtained by immersing a cylindrical ceramic mold into molten metal at constant temperature. The apparent thermal conductivity increased with amount of stucco and with the decrease in porosity. The apparent thermal conductivity increased in the order of fused silica particles, zircon sand, chamotte particles and fused alumina particles used as stucco. The apparent thermal conductivity obtained by immersing the sample into cast iron was a little larger than that obtained by immersing into aluminum. The thermal conductivity decreased with temperature when using zircon sand, chamotte particles and fused alumina particles as stucco. When using fused silica particles, the thermal conductivity did not change with temperature very much. With this method the apparent thermal conductivity and thermal conductivity as a function of temperature could be measured more rapidly than the pouring method, because the size of the sample was smaller and the temperature was measured only at the mold center and the metal-mold interface.抄録全体を表示PDF形式でダウンロード (671K) -
西 直美, 竹内 宏昌, 竹本 舜一, 河上 護1984 年 56 巻 6 号 p. 344-350
発行日: 1984/06/25
公開日: 2011/11/26
ジャーナル フリーAluminum alloys such as Al-0.5, 2.5, 5.2 and 5.5wt%Cu, Al-8.8wt%Mg, Al-1.0wt%Mn and Al-3.8wt%Ni were melted and poured on a chill block tilted 9 degrees and solidified. The flow rate of molten metal was constant. The surface of the chill block was polished and the temperature profile in the molten metal and chill block were examined by CA thermocouples. The heat transfer coefficient and the heat flux were calculated using the thermal balance equation. The surface layer structures of ingot were observed microscopically. The values of the heat transfer coefficient and the heat flux were independent of solute content and solute elements. Discs and predendrites were found on the surface layer of the ingot. The number of discs increased with increasing solute content, and the diameter of discs at the basal plane decreased with increasing solute content. The degree of microsegregation in the disc differed with the kind of alloying elements. The concentration of solute at the center of the disc increased by increasing the equilibrium distribution coefficient.抄録全体を表示PDF形式でダウンロード (719K) -
山田 始, 田中 他喜男1984 年 56 巻 6 号 p. 351-355
発行日: 1984/06/25
公開日: 2011/11/26
ジャーナル フリーMachinability, cutting temperature and the critical temperature on flank adhesion occurrence in the turning of spheroidal graphite cast irons were examined. The tool wear increased by increasing the amount of pearlite in the matrix. The wear in turning was greatest with JIS FCD70. The difference in the finished surface of the various kinds of spheroidal graphite cast irons was not notable. FCD70 gives the highest cutting temperature, while FCD40 gives the lowest which is nearly the same as gray cast iron. The critical cutting temperature producing flank adhesion goes down depending on the increase in the amount of ferrite in the matrix of this cast iron. For example, the flank adhesion occurs at and above cutting temperature of 1,100°C for FCD70, while it occurs at about 850°C in FCD40.抄録全体を表示PDF形式でダウンロード (586K) -
河部 昭雄, 若林 太, 近藤 靖彦1984 年 56 巻 6 号 p. 356-361
発行日: 1984/06/25
公開日: 2011/11/26
ジャーナル フリーRecently D-type graphite cast irons has come to be widely used with the spread of metal mold casting process. But it is not suitable for use under wear conditions and its use is limited, because the matrix is mainly composed of ferrite. A trial was made to obtain a bainite matrix structure in the as-cast condition in ordar to expand demand in iron castings. Generally, nickel and molybdenum are added to obtain the as-cast bainitic matrix, but it was found that the as-cast bainite matrix in the D-type graphite cast iron can be obtained by the addition of silicon and manganese, which are cheeper alloying elements. In order to explain this phenomena, TTT curves of the D-type graphite cast irons were measured. The effect of silicon and manganese on bainitization were discussed.抄録全体を表示PDF形式でダウンロード (812K)
- |<
- <
- 1
- >
- >|