巻号一覧
前身誌
79 巻, 10 号
選択された号の論文の16件中1～16を表示しています
- |<
- <
- 1
- >
- >|
-
村瀬 徹, 平井 直兄1993 年 79 巻 10 号 p. 1129-1137
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーPDF形式でダウンロード (7552K) -
松井 利郎, 筬島 豊1993 年 79 巻 10 号 p. 1138-1144
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーPDF形式でダウンロード (1177K) -
大友 崇穂, 田口 昇, 葛西 栄輝, 大森 康男, 川口 尊三1993 年 79 巻 10 号 p. 1145-1150
発行日: 1993年
公開日: 2010/02/16
ジャーナル フリーSintering experiments were carried out in order to clarify the mechanism of formation of large pore in the assimilated part in the sintering process of pisolite ore. Modeled briquette which consisted of disk-shaped pisolite ore as core and fine mixture of hematite ore and limestone as shell layer was used in the present experiments. The results obtained are summarized as follws :
1) When the shell layer was melted, large pore was formed in the assimilated part around the core ore.
2) The large pore in the assimilated part was formed by using not only unfired core ore but also that calcined at 800°C or 1300°C. It suggests that the water vapor generated by the dissociation of combined water in the ore was not only the cause of the large pore formation.
3) A mechanism of the formation of large pore in the assimilated part can be described by ; ( i ) The combined water in core ore is dissociated by heating, and macro-pores and/or cracks were formed in core ore. ( ii ) Gas in macro-pores and cracks in core ore is liberated because of its volume expansion during heating and by assimilation of core ore to the melt. ( iii ) The gas is caught around the ore because the viscosity of melt is increased by assimilation of the ore to melts. ( iv ) After cooling, the large pore in the assimilated part is formed around the core ore.抄録全体を表示PDF形式でダウンロード (13738K) -
野沢 健太郎, 柴田 耕一朗, 清水 正賢, Heinrich Wilhelm GUDENAU1993 年 79 巻 10 号 p. 1151-1156
発行日: 1993年
公開日: 2010/02/16
ジャーナル フリーThe knowledge on the microscopic reduction behavior of fine iron are in hot reducing gas flow is indispensable to accurate description of the extremely complex raceway combustion zone induced by PCI(Pulverized Coal Injection) and OI(fine iron Ore Injection) from blast furnace tuyeres. In the studies using the vertical flow reactor and the tube type reactor where fine materials were transported by the pressure difference in the gas chambers, and thereby a short residence time and a rapid heating rate of fine materials in the raceway combustion zone were simulated, the reduction degree of fine iron are as well as the reduction morphology were investigated in detail under the conditions of the combined injection(PCI+OI) and the carbon coated are injection. The experimental results revealed that the in-flight reduction degree of fine iron are was significantly increased mainly by the improved efficiency of contact of fine ore particles with reducing agents. And the carbon coating of the fine are surface achieved the most excellent condition for promoting the in-flight smelting reduction.抄録全体を表示PDF形式でダウンロード (10563K) -
小林 三郎, 石垣 政裕, 稲葉 晉一1993 年 79 巻 10 号 p. 1157-1163
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーThe pneumatic conveying is a useful technique which is used to provide powder materials such as fine coals, ores or fluxes to the metallurgical furnaces. The present paper describes the monitoring technique to distinguish between the two flow regimes of solid particles ; the dispersive and the sliding flows in the reverse T-type tube junction where alumina particles fall vertically and are conveyed by a horizontal nitrogen flow.
The flow regimes of the alumina particles were monitored by means of two kinds of indexes; the pressure difference fluctuation of the gas in the tube and the acoustic effect on the tube wall. For this purpose, two pressure transducers were equipped to the tube and two acceleration pick up sensors were touched directly on the outer surface of the tube.
In the range of Froud number greater than 8, the pressure index is significantly large for the dispersive flow, while small for the sliding flow. In the range of Froud number less than 8, the acoustic index is, in contrast to the above, significantly large for the sliding flow, while small for the dispersive flow. The simultaneous application of both indexes will increase the monitoring reliability.抄録全体を表示PDF形式でダウンロード (1062K) -
原 茂太, 菅野 浩至, 荻野 和己1993 年 79 巻 10 号 p. 1164-1168
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリー(BaO+CaO)-(BaF2+CaF2)系への炭酸ガスの溶解度を熱天秤法により1674Kで決定した。その結果,この系に対する炭酸ガスの溶解度は最初に配合されたBaO濃度には依存せず, BaO(1)+CaF2(1) = CaO(1) + BaF2(1)で示される置換反応の平衡値Kpで決まる融体中のBaO濃度に比例して変化することが分かった。この考え方を拡張してBaO-CaO-BaF2系およびCaO-NaF系フラックスによる高炭素鉄クロム合金液体の脱りんに関して報告された結果に検討を加えた。このような酸化物-ハロゲン物系フラックスにおいては,炭酸ガスの溶解度の場合と同様に,これらが置換塩系を作ると仮定すると,配合フラックス組成と脱りん率との関係が整理できることを示した。抄録全体を表示PDF形式でダウンロード (672K) -
山本 広一, 長谷川 俊永, 高村 仁一1993 年 79 巻 10 号 p. 1169-1175
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーThe effect of B on microstructure and toughness at the heat affected zone after welding thermal cycle simulations, has been investigated in steels containing titanium oxide particles. The titanium oxide is identified as Ti2O3 with cation vacanies, which contribute to preferential nucleation of MnS and TiN precipitates on Ti2O3. The Mn-depleted zone is formed around Ti2O3 after the MnS precipitation. The Ti2O3 particles with TiN and Mn-depleted zone act as preferential nucleation sites for intra-granular ferrite. The segragation of B at austenite grain boundaries suppresses effectively the nucleation of grain boundary ferrite. While ferrite nucleation at the interface between Ti2O3 and austenite matrix, is not affected by B addition because of B-depleted zone arisen from the diffusion of segregated B into Ti2O3, via cation vacancies. Consequently the B addition to steels with Ti2O3 promotes the formation of fine intragranular ferrite grains so that the heat affected zone toughness is improved even after large heat input welding.抄録全体を表示PDF形式でダウンロード (15770K) -
田川 哲哉, 宮田 隆司, 粟飯原 周二, 岡本 健太郎1993 年 79 巻 10 号 p. 1176-1182
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーFormation of martensitic islands is one of the most significant causes of deterioration in toughness of multi-pass weld heat-affected zone of high tensile strength steels. This paper presents the influence of the size and the volume of the martensitic islands on the primary mechanical properties and the cleavage fracture toughness of steels simulated to intercritically reheated grain coarsened HAZ of multi-pass weld. Various thermal cycles simulated to HAZ were applied to five kinds of laboratory melted steels produced by hot rolling, direct quenching and tempering process to reproduce of different states of the martensitic islands. The states of the martensitic islands represented by the average and the maximum size, the volume fraction and the aspect ratio were investigated in correlation with the thermal cycles. The yield and tensile strength increased with the increase of the volume fraction of the martensitic islands. However, the toughness was so sensitive to the formation of the martensitic islands that small amount of the martensitic islands significantly decreased the toughness.抄録全体を表示PDF形式でダウンロード (7306K) -
田川 哲哉, 宮田 隆司, 粟飯原 周二, 岡本 健太郎1993 年 79 巻 10 号 p. 1183-1189
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーIn the previous work, the state of the martensitic islands and its influence on the fracture toughness in low carbon steels simulated to the heat affected zone of multi-pass weld were investigated.
It has been shown by the authors that cleavage fracture toughness of steels can be described in terms of the cleavage fracture stress and yield stress of materials.
In the present work, experimental results in the previous work were analyzed along with the local criterion approach, and successful correlations were obtained. Through this correlation, the influence of the martensitic islands on the deterioration in toughness was investigated. It was suggested that the maximum size of martensitic islands was not an unique metallurgical factor which deteriorated the toughness, and mean free path and the statistical distribution of the martensitic islands had also a great influence on cleavage fracture toughness.抄録全体を表示PDF形式でダウンロード (3936K) -
莫 建平, 柴田 昭, 宮原 一哉, 細井 祐三1993 年 79 巻 10 号 p. 1190-1196
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーThe effects of thermomechanical treatments (TMT;warm working and ausforming) on the high temperature deformation behaviors of high carbon and high chromium steels (SKD11 die steels with 1.5%C-12%Cr) are investigated. Thermomechanically treated steels yield very fine ferrite grains of 0.3 to 0.6μm. When tensile tested just below the Ac1 temperature, the elongation of non-thermomechanically treated material is 130%, whereas, the ausformed material shows 320% elongation. The raise in ductility indicates the beneficial effect of TMT due to the refinement of microstructure. Image analysis on the grain-elongation during deformation of the materials shows that the degree of grain-elongation along the tensile axis in the finer grained material is smaller. This means that in the relatively finer grained materials, the contribution of the grain-elongation to the deformation of the materials is smaller but the contribution of grain boundary sliding is larger, compared to that of deformation of coarse grain materials.抄録全体を表示PDF形式でダウンロード (9149K) -
河面 弥吉郎, 中島 正三郎, 高嶋 邦秀, 原勢 二郎1993 年 79 巻 10 号 p. 1197-1203
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーA study was made on the effect of the inter-pass aging during cold rolling on the secondary recrystallization of the grain-oriented electrical steel with Sn produced by the single-stage cold rolling process. The following conclusions were obtained.
(1) The specimen without Sn yields a perfect secondary recrystallization structure in case of no inter-pass aging and 200°C inter-pass aging, but no secondary recrystallization in case of 300°C inter-pass aging. This failure of secondary recrystallization is attributed to the smallest amount of the product of {110} and {111} densities in the primary texture, that is, the smallest opportunity of meeting for Goss nuclei with easily consumable grains by them. The specimen with Sn yields a perfect secondary recrystallization structure in all cases of the inter-pass aging mentioned above. This is attributed to the small size of primary grains, the large amount of the product of {110} and {111} densities in the primary texture, and the large amount of effective inhibitors.
(2) The core loss of the specimen with Sn cold rolled with the inter-pass aging is very small because of the high magnetic flux density and the small size of secondary grains.抄録全体を表示PDF形式でダウンロード (7473K) -
中村 展之, 高木 節雄, 鎌田 政智, 徳永 洋一1993 年 79 巻 10 号 p. 1204-1209
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーSintering and nitriding behaviors of 12mass% Cr ferritic stainless steel (SUS410L) powder compacts in nitrogen gas atmosphere were investigated by means of optical microscopy and chemical analysis. Kinetics of the austenitization by nitriding was also discussed in terms of nitrogen diffusion within austenite grain and along grain boundaries.
The results obtained are as follows:
(1) At sintering temperature of 1473K in nitrogen gas atmosphere, about 0.26mass% of nitrogen is absorbed into the steel powders through open pores during heating to the sintering temperature, and ferritic phase changes to austenite owing to nitrogen absorption. Therefore, sintering proceeds in the state of austenitic structure at 1473K and then austenite transforms to martensite on cooling to room temperature after the sintering treatment.
(2) Grain boundaries within powder particles play a role of free path for nitrogen diffusion, so that the austenitization by nitriding in ferrite powder particles proceeds not only from the particle surface but also from grain boundaries within each powder particle.
(3) Nitriding rate greatly depends on the grain size within powder particles, although it is dependent on particle size itself when particles are of single crystal. As the grain size within powder particles becomes smaller, nitriding rate is increased.抄録全体を表示PDF形式でダウンロード (11115K) -
草開 清志, 早川 到, 大岡 耕之1993 年 79 巻 10 号 p. 1210-1216
発行日: 1993年
公開日: 2010/02/16
ジャーナル フリーThe growth behavior of cellular δ phase in Ni-base alloy, modified Inconel X-750 type alloy (X-750M), was investigated mainly by optical and transmission electron microscopy.
The values of n in Johnson-Mehl's equation for the growth of the cellular δ phase in X-750M aged in various conditions after a solution heat treatment were estimated to be 1.69-1.84.
The values of n in the case of pre-aged X-750M at 943K for 253ks after a solution heat treatment followed by aging in various conditions, were estimated to be 1.44-1.67. The obtained value of n suggested that the growth of the cellular δ phase in X-750M after the pre-aging treatment obeyed a volume diffusion rate control with zero nucleation rate. Transformation curves of γ + γ'' phases to the cellular δ + γ phases in the specimens aged after the pre-aging treatment were consistent with a theoretical one. The apparent activation energy for the growth of the cellular δ phase in X-750M aged after the pre-aging treatment was estimated to be 232kJ/mol, which is nearly equal to those for diffusion of solute atoms in the alloy.抄録全体を表示PDF形式でダウンロード (7695K) -
栗田 満信1993 年 79 巻 10 号 p. N704-N710
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーPDF形式でダウンロード (4420K) -
小野 陽一1993 年 79 巻 10 号 p. N711-N715
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーPDF形式でダウンロード (656K) -
不破 敬一郎1993 年 79 巻 10 号 p. N716-N720
発行日: 1993年
公開日: 2009/06/30
ジャーナル フリーPDF形式でダウンロード (953K)
- |<
- <
- 1
- >
- >|