巻号一覧
前身誌
58 巻, 3 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
- >
- >|
-
中村 信夫1972 年 58 巻 3 号 p. 373-374
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーPDF形式でダウンロード (2019K) -
井口 義章, 井上 道雄1972 年 58 巻 3 号 p. 375-386
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーSynopsis:
It is generally recognized that iron oxide pellets reduced by hydrogen at lower temperature are easily re-oxidized by the atmosphere even at room temperature. However, those pellets which were slightly re-oxidized by the inert gas containing the lower oxygen potentials showed inactive behaviors. Very thin oxide layer of less than 9 Å thickness was formed on the pore surface of the pellet during re-oxidation with N2-O2 gas mixture of below 1% O2 content. When O2 content in the gas mixture was below 1%, re-oxidation degree was nearly 0.9% independent of oxygen potential. But if the O2 content exceeded 1%, the re-oxidation degree increased rapidly with the O2 content.
It was also shown that the rate of the re-oxidation was controlled by the diffusion of oxygen through the boundary layer and the reacted shell layer. Therefore, the exposure time necessary for inactivation could be calculated and it was dependent on the oxygen potential.
Furthermore, when the resistance of the gas transport could be negligible, the rate of the re-oxidation was represented by the logarithmic rate law.抄録全体を表示PDF形式でダウンロード (4255K) -
根本 秀太郎, 川和 高穂, 佐藤 秀樹, 阪本 英一1972 年 58 巻 3 号 p. 387-394
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーSynopsis:
A number of new casting techniques to produce steels for sheet and coil in continuous casting have been developed and quality of continuously cast slabs with 200×1600 mm2 and products have been investigated. The results are summarized as follows.
1) It is desirable to decrease oxygen content as low as possible by pre-deoxidation before aluminum addition in converter.
2) A new method, which is characterized by Al-wire addition with rapid rate into molten steel stirred by inert gas injection in ladle, has been developed. This method results in increase of yield and accurate control of soluble Al content in steel.
3) The inert gas purging from the bottom of ladle gives a uniform bath temperature and is very beneficial in cleaning the bath.
4) A new sealing method for perfectly preventing the oxidation of steel stream from open air has been developed. By the application of this method, the content of inclusions in steel has been reduced to 20 to 40 ppm, which have been calculated in terms of oxygen content in steel in tundish.
5) A new nozzle is designed so that stagnant zone of steel bath is not formed in mold.抄録全体を表示PDF形式でダウンロード (3032K) -
松山 晋作1972 年 58 巻 3 号 p. 395-410
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーEffects of tempering condition, prior-austenite grain-size, and shape of test specimen on the behavior of hydrogen-induced delayed fracture have been investigated for several low alloysteels for high strength bolt. The main results are as follows;(1) The tempering at temperatures above 500°C improves the resistance to delayed fracture, except for secondary hardenable steels. This resistance depends on the strength level and the strain hardening behavior.(2) Both steels with fine (ASTM 9-10) and coarse (ASTM 0-3) grains of prior-austenite have a tendency to be more susceptible to delayed fracture than these with medium grain size (ASTM 4-5).(3) The thinning of specimen width results in decreasing of the susceptibility to delayed fracture owing to the change of stress condition, from plain strain to plain stress.抄録全体を表示PDF形式でダウンロード (9848K) -
成広 清士, 乙黒 靖男, 大坪 孝至, 三井田 陞1972 年 58 巻 3 号 p. 411-422
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーA study was made of the mechanical properties and hardenability of medium carbon chromium steel which was developed as corrosion resisting steel under weak acid corrosive atmosphere.
It was proved that retained hydrogen had an extremely bad effect especially on the ductility of this steel. Therefore, the process of production was investigated in order to increase the ductility.
As the effect of boron on hardenability was different with nitrogen content, the relation between the effect of boron and content of such nitride forming elements as aluminum and titanium was examined.
The following results were obtained.
(1) In order to guarantee 8 percent of elongation (JIS No 4 tensile specimen) in steel with 140 Kg/mm2 of tensile strength, hydrogen content had to be kept less than 1 ppm. Hydrogen content was decreased less than 1 ppm by slow cooling of the bloom after blooming.
(2) The effect of boron on hardenability was remarkable in steels containing nitrogen of less than 40 ppm even if only boron was added to the steels. But in order to make boron more effective for hardenability, aluminum more than 0.01 pet., and aluminum more than 0.04 pet. or titanium more than 0.02 pet. were required for steels containing about 0.006 pet. of nitrogen and for steels containing about 0.01 pet. of nitrogen respectively.
(3) The effect of boron on hardenability corresponded with content of acid soluble boron which was decided by solubility products of (B)(N), (Al)(N) and (Ti)(N). But in all cases, the relationship between hardenability and the content of acid soluble boron did not always hold good.
In steels containing aluminum, the content of acid soluble boron which was necessary to secure the same hardenability was much smaller than the content in steels without addition of aluminum.
(4) It was proved from the investigation on distribution of boron by α-track method that the hardenability was related to the concentration of boron on pre-austenite grain boundaries in steel without addition of aluminum.抄録全体を表示PDF形式でダウンロード (10378K) -
斎藤 利生1972 年 58 巻 3 号 p. 423-433
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーSome Hadfield steels with 1%Si, 2%Al, 0.8% Mo, 4% Cr, or 0.5%V were studied mainlyby micrography on isothermal carbide precipitation after solution treatment. Isothermal precipitation diagrams for all steels were determined as C-urve, fundamentally similar to that of standard Hadfield steel. By addition of 1% Si, the carbide precipitation in steel was little affected, but the temperature range in which pearlitic constituent (PC) appeared was slightly extended. By addition of 2%Al, the grain boundary carbide precipitation in high temperature range was accelerated, but the transformation into PC wasretarded and its temper ature range was limited in a slightly narrower range. Moreover, matrix precipitation of carbide in high temperature range was disturbed remarkably by addition of Al. By addition of carbide forming elements such as Mo, Cr, and V, the precipitation of carbide was accelerated especially in high temperature range, and the precipitation temperature range was extended to higher temperature. However, transformation into PC was retarded by addition of these elements, and addition of Cr +V was markedlyeffective. By addition of 4% Cr and 4% Cr+0.5% V, matrix carbide precipitation in steel was remarkably accelerated, and its precipitation area formed a C-urve, which had a nose at 825× in the former steel, and at 800× in the later steel. Addition of V was markedly effective for precipitation hardening of steel. It is considered that the retarding behavior of transformation into PC by addition of carbide forming elements was similar to that by lowering carbon content in steel. In microstructures of V-added steel, peculiar platelet PC which was different from nodular PC in other steels was observed. The formation ofthe platelet PC is considered to be due to a large quantity of platelet carbide precipitation in steel by addition of V.抄録全体を表示PDF形式でダウンロード (10073K) -
大谷 泰夫, 寺崎 富久長, 邦武 立郎1972 年 58 巻 3 号 p. 434-451
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーThe impact properties of some high tensile strength steels were investigated in relation to the austenite grain size and the cooling rate.
The results showed the existence of optimum cooling rates for the transition temperature. The optimum cooling rate depended on the hardenability of steels, and as the austenitizing temperature was raised it shifted to the lower cooling rate.
The electron microscopic observation revealed that the structure with superior impact properties was the duplex martensite-bainite structure. The morphology of carbide in this bainite was similar to that in the lower bainite, but the trace analysis for such bainite revealed that it had the same lath-like morphology with a ‹111› α {110} α as that in the upper bainite and the lath martensite.(This bainite in a low-carbon low-alloy steel was named as Bainite-III type in a previous paper.)
The orientation measurements of facet pit and fracture surface clarified that the cleavage plane was (100). Based on the direct observation of fracture surface by scanning electron microscope, the unit crack path was defined. The unit crack path showed experimentally a better correlation to the transition temperature than the austenite grain size.
These results suggested that the role of bainite in the duplex structure was the partitioning of austenite grain prior to the martensite transformation.抄録全体を表示PDF形式でダウンロード (18714K) -
松村 洽, 鎌田 晃郎1972 年 58 巻 3 号 p. 452-463
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリー3%珪素鉄を70%1次冷延し, 8000Cで30min脱炭焼鈍したものを出発材料として, 歪焼鈍法による単結晶作製のための種結晶の成長条件をさだめ, あわせて結晶粒成長および再結晶集合組織形成の過程をしらべた。その結果は次のように要約される。
1) 前歪が数%程度の引張では種結晶は成長しないが, 冷間圧延によれば, L方向に圧延してもC方向に圧延しても, 圧延率が20%から60%までの非常に広い範囲で十分に成長した種結晶が得られる。
2) L方向に圧延した場合, 得られる種結晶は常に (110)[001] すなわちGoss方位である。
C方向に圧延した場合, 低圧延率では1次冷延の方向にGoss方位をとる (110)[110] 方位の種結晶が成長し, 高圧延率側では新しい圧延方向 (前歪圧延の方向) にGoss方位をとる種結晶ができる。圧延率30%前後がこれらの遷移領域であり, Goss方位と (110)[110] 方位の種結晶の混在したものが得られる。
3) C方向に種々の圧延率の前歪を与えたのち粒成長の状況をしらべると, 30%以下の圧延率では焼鈍前の粒界の移動により, また30%以上の圧延率ではnucleationand growthの過程により1次再結晶する。その後10%程度の前歪ではnormal grain growthがおこり2次再結晶しないが, 20%以上の圧延率ではnormal graingrowthが抑制され高温で2次再結晶する。種結晶が得られるための必要条件は2次再結晶が行なわれることである。
4) 圧延集合組織, 1次再結晶集合組織ともL方向圧延材とC方向圧延材とではかなり異なるが, 2次再結晶後の種結晶はGoss方位または (110)[110] 方位が成長する。この場合, 圧延集合組織中の {111}〈112〉成分が重要な役割をはたすものと考えられる。
5) 低圧延率の前歪では, その圧延方向によらず1次圧延方向にGoss方位をとる種結晶が成長する。つまり焼鈍前粒界の移動により1次再結晶が行なわれる場合, 前歪の方向には影響されない。したがつて素材を切る方向によつて, (110) 面が板面に平行で [001] 方向が任意の向きの種結晶が得られる。
終わりに, 発表にあたりご指導下さつた藤元克巳研究所次長ならびに鶴岡一夫物理研究室長, また発表を許可された今井光雄研究所長に厚く御礼申し上げます。また本研究について非常に有益なご批評とお励しをいただいた東京大学工学部阿部秀夫教授に深く感謝いたします。抄録全体を表示PDF形式でダウンロード (11754K) -
北川 和夫, 関 文男, 上田 益造1972 年 58 巻 3 号 p. 464-471
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーThe influence of intermittent friction on wear phenomena of plain carbon steel (S33C) was investigated using high frequency induction hardened steel (S45C) as standard test piece.
The test was performed by means of rolling friction method having 15% slip without any lubricants, and in addition to the comparison of wear loss, wear particles and sliding surface were analized by X-ray diffraction method.
Results obtained are as follows.
1) Wear loss increases as the intermittent frequency and stopping time increase.This is due to that oxide produced on sliding surface is not sufficient.
2) Hardened steel have a good wear resistibility to intermittent friction and with increasing hardness the proportion of αFe2O3 in wear particles increases.
3) Under a small load there is little difference of wear loss for intermittent and continuous friction.
4) Intermittent friction causes a big plastic deformation on sliding surface.抄録全体を表示PDF形式でダウンロード (3560K) -
若松 茂雄1972 年 58 巻 3 号 p. 472-481
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーThis work, a part of a general program of research on the state analysis of steel, was carried out to develop a simple method for extraction and determination of molybdenum carbides [(Fe, Mo) 3C and Mo2C] in low alloy steel. The procedure is as follows:
1. Extraction of molybdenum carbides from steel.
(a) Cover the steel sample with close-texture filter paper as a diaphragm, connected as an anode, is dissolved into 100 to 130ml of 1% NaCl-5% EDTA electrolyte (H 6 to 7) at a current density of 50mA/ cm2 for 1 to 2 hr. Remove the anode and the residue is collected into an Erlenmeyer flask. To the residue add 20ml of 6N HCl and pass in a stream of argon gas for 10 min at room temperature.
(b) Filter and wash with water. Add 5 ml of HNO3 and 10ml of HC1O4 to the filtrate and evaporate to dense white fumes. Cool dilute to 100 ml and determine Mo as (Fe, Mo) 3C in accordance with section 2.
(c) Transfer a quarter of the electrolyte to a beaker. Add 20ml of HNO3 and 10ml of HC1O4 and evaporate to dense white fumes. Cool, dilute to 100 ml and determine Mo as solid solution in accordance with section 2.
(d) Transfer the paper and residue (paragraph (b)) to a beaker, and 30 ml of HNO3 and 10 ml of HC1-O4 and evaporate to dense white fumes. Cool, dilute to 100 ml and determine Mo as Mo2C in accordance with section 2.
2) Photometric determination of molybdenum.
Transfer 10 to 20 ml of each of solutions (section 1 (b), (c) and (d)) to 50ml volumetric flasks. If the iron contents is less than 40 mg, add iron solution (0.02g Fe/m/) until a total of40 to 50 mg of iron. To each flask add 5 ml of thiourea solution (10%), 8 ml of HC1O4, 2 ml of NaCNS solution (30%) and 10 ml of ascorbic acid solution (5%), dilute to 50 ml and let stand for 10 min. Measure the absorbance of solution against water at 460 mu.
A complete analysis can be carried out in 3 to 4 hr.抄録全体を表示PDF形式でダウンロード (4448K) -
成田 貴一, 宮本 醇, 松本 洋1972 年 58 巻 3 号 p. 482-494
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーA fundamental study of isolation and determination of titanium compounds in steels was carried out by means of hydrochloric acid, sulphuric acid, phosphoric acid, bromine-ester, iodine-alcohol, and potentiostatic electrolysis methods.
The results are as follows:
1. According to the experimental results on chemical behaviors of various synthesized titanium compounds,
(1) Titanium carbide, TiC is very stable in mineral acids, but easily decomposed in oxidizing reagents.
(2) Titanium nitride, TiN is decomposed in nitric acid, while in other mineral acids it is slightly decomposed at elevated temperatures.
(3) Titanium oxides, the higher the valency of titanium, the more stable the oxide is. And ferrous titanium oxides are attacked in mineral acids.
(4) Above-mentioned titanium compounds, TiC, TiN and titanium oxides, are very stable in iodinealcohol and bromine-ester.
(5) Titanium sulphides, TiS and Ti3S4 are unstable in mineral acids and easily decomposed in iodinealcohol, bromine-ester and other oxidizing reagents.
2. Carbide, TiC in steels can be extracted by any methods quantitatively.
3. Nitride, TiN in steels is also extracted by any methods but the isolated TiN is gradually decomposed in mineral acids.
4. For isolation of titanium compounds in steel, the electrolytic method is desirable, because in acid and halogen-organic solvent the unstable compounds such as TiO, 2FeO·TiO2, TiS and the precipitates of very fine particles are attacked slowly.
5. Chemical separation of synthesized titanium carbide, nitride, oxide and sulphide is possible, but chemical behavior of inclusions and precipitates in steels are affected by their size, disorder of their lattice and coexisting elements so that accurate separation is very difficult.抄録全体を表示PDF形式でダウンロード (2803K) -
吉森 孝良, 平手 直之1972 年 58 巻 3 号 p. 495-500
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーSeveral slags were potentiometrically titrated in molten potassium nitrate. The sample was allowed to react with a definite amount of potassium dichromate in the melt at 400°C, and then the excess dichromate was titrated back with the weighed portions of potassium carbonate. An antimony rod was used as the indicator electrode, and a Pt/Pt (II) couple in a eutectic mixture of LiCl-KCl asthe reference electrode. The potential break through the end-point was 0.2-0.3V, and reproducible results could be obtained for each slag sample. The amounts of the acid consumed by the slags were compared with the basicities of the samples, which were calculated from various methods. Almost linear relationship could be obtained between the amounts of the acid required and the following basicities based on the chemical analyses of the samples; they are lime-silica ratio, V-ratio, basicity ratio, the basicity by KERLIE and the basicity by MORI.抄録全体を表示PDF形式でダウンロード (968K) -
木原 諄二1972 年 58 巻 3 号 p. 501-518
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーPDF形式でダウンロード (4922K) -
的場 敏夫1972 年 58 巻 3 号 p. 519-532
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーPDF形式でダウンロード (3211K) -
岡崎 和, 河島 磯志1972 年 58 巻 3 号 p. 533-548
発行日: 1972/03/01
公開日: 2010/10/12
ジャーナル フリーPDF形式でダウンロード (2397K) -
1972 年 58 巻 3 号 p. 549-555
発行日: 1972/03/01
公開日: 2010/12/22
ジャーナル フリーPDF形式でダウンロード (2057K)
- |<
- <
- 1
- >
- >|