巻号一覧
31 巻, 1 号
選択された号の論文の19件中1～19を表示しています
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仁木 栄次, 正藤 和男1967 年 31 巻 1 号 p. 1-5
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーEach phase of TiC-Ni cermet was studied by means of electrolytic separation and chemical analysis, X-ray diffraction and micro-hardness measurement, with the following results:
The solubility of TiC in Ni phase was determined to be 2.7Ti+C, 3.4Ti+C and 5.3Ti+C (in wt%) at 1200°, 1250° and 1300°C, respectively. Although it is considered that Ti dissolves substitutionally in Ni and C dissolves interstitially in it, but the content of C in the solid solution is considerably small as compared with that of Ti. Thus, it is reasonable to consider that free C is present in the phase of the vertical section between Ni and stoichiometric TiC in the Ni-Ti-C system. And it appears that Ni dissolves substitutionally in TiC.
The lameller deposit observed in about 90%Ni composition is TiC (a0=4.317 Å). The micro-hardnesses (Hv, 25 g Load) of the Ni and TiC phases were measured to be about 280 kg/mm2 and about 3200 kg/mm2, respectively.抄録全体を表示PDF形式でダウンロード (497K) -
後藤 秀弘, 並木 美智子1967 年 31 巻 1 号 p. 5-8
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーSimultaneous determination of Pb and Zn in iron, steel and iron ores by the D.C. polarographic method has been studied. After several supporting electrolytes had been tested, the following procedure was established. Iron the major constituent, in the dissolved samples, is removed by extraction with Methyl Isobutyl Ketone. The final solution was adjusted to contain 1 N NaOH as supporting electrolyte. D.C. polarograms were obtained at −0.4 to −0.9 V for Pb and at −1.1 to −1.6 V for Zn against Hg pool, and the amounts of Pb and Zn were determined from the calibration curves, respectively.
This method was succesfully applied to determination of Pb and Zn in iron, steel and iron ores. More than 0.01%Pb and Zn were determined rapidly with satisfactory results.抄録全体を表示PDF形式でダウンロード (299K) -
井川 博, 近藤 明, 土居 定雄1967 年 31 巻 1 号 p. 9-13
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーOn the low Ni-Cr cast iron containing approximately 1.0 to 3.0%Ni and 0.5 to 1.5%Cr, the effect of the Ni contents on the thermal expansion, growth, resistance to oxidation and microstructure, which are the basic properties of low alloy heat-resisting cast iron, were studied. The results obtained are as follows:
(1) Mechanical properties of cast iron containing approximately 2.0%Ni and 1.5%Cr are good. When the Ni content is increased to about 3.0%, almost same values are obtained in relation to the tensile strength irrespective of the Cr content.
(2) Cast iron containing approximately 2.0%Ni and 1.5%Cr indicates the lowest thermal expansion value. When Ni content is increased to about 3.0%, a tendency of expansion is recognized.
(3) Cast iron containing approximately 2.0%Ni and 1.5%Cr also indicates the lowest value in growth rate. The growth rate becomes clearly larger with increasing Ni content.
(4) A similar tendency is observed between the resistance to oxidation and at the growth rate, but the effect of the Ni content on the weight gain is somewhat stronger than that of the Cr content.
(5) Plain cast iron is poor in thermal expansion, growth rate, and resistance to oxidation. At some testing temperatures, however, the above cast iron is superior to cast iron containing a small amount of Ni and Cr.
(6) On the microstructure of cast iron containing approximately 1.0 to 2.0%Ni, graphite becomes smaller and cementite increases with increasing Cr content. When the Ni content is increased to about 3.0%, graphite becomes larger and cementite decreases to some extent.
It is concluded that the Ni content ranging from 1.0 to 2.0% acts effectively on the basic properties of low alloy heat-resisting cast iron in the range of Cr contents from 0.5 to 1.5%, but an undesirable effect appears when the Ni content is increased to about 3.0%.抄録全体を表示PDF形式でダウンロード (760K) -
鈴木 寿, 川勝 一郎, 北野 均, 村瀬 昭次1967 年 31 巻 1 号 p. 14-19
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーIt has been previously reported that high zirconium Cu-Zr alloy is very interesting as high-strength and high electrical conductivity alloy, compared with conventional low zirconium Cu-Zr alloy containing about 0.3%Zr.
Effects of the additional elements on the properties of Cu-about 1.3%Zr alloy were studied, aiming at improvement of their properties. Each element such as Be, Ti, Cr, Fe, Ni, Co, misch metal, Al, Si, As, Ag, Cd, Sb, and Te was added at a rate of less than about 0.5% to the straight alloy. Specimens were cast, hot-worked at about 850°C, solution-annealed at 880°∼890°C for 40 min, quenched and finally cold-rolled by about 83% to become 0.5 mm thickness sheets. Properties of the specimens in various aged states were examined.
The results obtained were as follows: (1) Hardness increased with increasing additional elements, excepting the addition of misch metal and Sb which caused a decrease in hardness. (2) Tensile strength was generally improved with increasing additional elements, particularly by the addition of Ti, Cr, Co and a very small amount of Si. (3) Elongation at half-softening-temperature decreased generally with the additions. (4) Electrical conductivity decreased slightly with increasing additional elements except Ti, Fe and Al. (5) Softening resistance and high temperature hardness were improved by the addition of Cr, Co, Si and As. (6) Oxidation resistance was also improved by the additional elements except Te. (7) It was found that the alloys of Cu-Zr-Cr, Cu-Zr-Co and Cu-Zr-Si systems were superior to the others as well as to the binary alloy, as high-strength, conductivity and heat resistance materials.抄録全体を表示PDF形式でダウンロード (1340K) -
菊池 武昭, 黒沢 利夫, 柳橋 哲夫1967 年 31 巻 1 号 p. 19-25
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーThe thermal behaviors of bauxites used as the source materials in the direct reduction of aluminium were investigated.
By the microscope observation under cross Nicols, it was found that the texture of Australian bauxite was composed of fine gibbsite crystals and the crystals were finer than the Bintan and Sematan bauxites.
The outer skin of the Australian ore particles and smaller particles had a much higher boehmite content than the central and larger samples.
According to thermobalance, every sample had a small amount of adsorbed water.
The change of gibbsite was mainly due to the formation of χ-Al2O3, and less than 20% of gibbsite was transformed to boehmite, and above 1000°C all the samples changed to α-Al2O3.
From the decrease in intensity of infrared absorption and neuclear magnetic resonance, an indication of decomposition of gibbsite was found in the samples heated for 1 hr at 110°C.
In addition, the free water due to decomposition of the O-H group was detected in 1600 cm−1 of infrared absorption and 1 gauss of neuclear magnetic resonance, and a larger quantity of the free water was found in the samples heated at 310°C, for 1 hr than in those treated at 110°C.
This free water was assumed to be a solvent which takes part in dissolution and precipitation during the transformation of gibbsite to boehmite.
Furthermore, owing to the more developed gibbsite crystal in the Bintan bauxite, a small quantity of water was still found in the sample calcined at 700°C.抄録全体を表示PDF形式でダウンロード (1591K) -
増本 量, 斎藤 英夫, 菊地 紀雄1967 年 31 巻 1 号 p. 25-30
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーSingle crystals of cobalt having long length were prepared and their thermal expansion and Young’s modulus were measured over the temperature range from −100° to 350°C by a dilatometer and by means of a vibrator-controlled oscillator, respectively. From the measured values and the known values of volume compressibility, the elastic parameters, the elastic constants and the rigidity modulus were calculated. The thermal expansion coefficient, Young’s modulus and rigidity modulus for a poly-crystal were calculated and the calculated values agreed well with the measured values in melted poly-crystal specimens.抄録全体を表示PDF形式でダウンロード (392K) -
武井 英雄, 大森 正信, 吉永 芳豊, 渡部 信三1967 年 31 巻 1 号 p. 31-36
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーThe purpose of this report is to examine some mechanical properties—ultimate tensile strength, elongation, Vickers hardness, Charpy impact value and endurance limit—of the ausformed 9%W-3%Cr tool steels and to compare their properties with the same steels heat-treated conventionally. The results obtained are as follows:
(1) The ultimate tensile strength and Vickers hardness increase almost lineally manner with increase in the amount of deformation (reduction in thickness) at ausforming, and the rate of increase per 1% reduction is 0.7 kg/mm2 for the ultimate tensile strength and 2.2 for the Vickers hardness.
(2) The effect of deformation temperature on the ultimate tensile strength, hardness and elongation can hardly be observed over the temperature range (500°∼600°C) in this investigation.
(3) The elongation decreases slightly with increase in deformation at ausforming, but when the amount of deformation exceeds a certain degree (for instance, 70% reduction for the deformation temperature 600°C, 65% for 550°C and 50% for 500°C) the elongation decreases rapidly.
(4) The ausformed steel is superior to the conventionally hardened steel in the ultimate tensile strength and hardness, but slightly inferior in the elongation and impact strength. And the difference of these properties between the two steels does not change up to the tempering temperatures of 550°∼600°C.
(5) The impact strength of the ausformed steel decreases slightly with increase in the amount of deformation.
(6) The fatigue life and endurance limit of the ausformed steel tempered at 500°C are about 5 and 1.5 times as large as those of the steel conventionally heat-treated, respectively.
(7) The energy transition temperature is −150°C for the ausformed steel (tempered) and −130°C for the conventional steel.抄録全体を表示PDF形式でダウンロード (977K) -
阿部 秀夫, 伊藤 邦夫, 福元 亮一1967 年 31 巻 1 号 p. 37-42
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーThe textures of Fe-30.2 wt%Ni alloy sheets rolled at 150°C and subjected to a sub-zero treatment and annealings were determined by the X-ray pole figure method to study the selection of the orientation relationships in the martensitic transformation of the deformed γ-phase and the correlation between the α→γ transformation and the recrystallization.
The texture of the α-phase transformed from the deformed γ-phase by the sub-zero treatment cannot be explained in terms of the equal probability for the 24 crystallographically equivalent Greninger-Troiano’s orientation relations.
The preferred orientations estimated from the maxima of the pole density in the observed pole figure of the α-phase coincide with the orientations derived from (321)[658]γ and (211)[\bar111]γ by the relation: (111)γ\varparallel(101)α, [\bar110]γ 2.6° from [\bar1\bar11]α, [0\bar11]γ 7.9° from [1\bar1\bar1]α, and [1\bar21]γ 2.6° from [10\bar1]α.
On annealing after the sub-zero treatment, the α→γ transformation occurs at 500°C and the γ-phase recrystallizes at 600°C.
The recrystallization texture is not altered by the sub-zero treatment. Main orientations represented by the maxima of the pole density in the recrystallization texture are related to the (211)[\bar111] orientation in the rolling texture by 30°∼40° rotations about ⟨111⟩ axes.抄録全体を表示PDF形式でダウンロード (615K) -
竹内 栄, 本間 敏夫, 佐藤 経郎, 園田 晋, 川井 浩, 小山 恵二1967 年 31 巻 1 号 p. 42-48
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーVarious experiments for the reduction of thoria by calcium have been performed to determine the most industrially favorable condition for preparing thorium metal. The results obtained are as follows:
(1) Stainless steel having no surface lining is the most suitable material for a reactor vessel, while the yield deteriorates in the case of a graphite reactor vessel.
(2) The optimum particle size of thoria is about 150 μ.
(3) A high yield of metal can be obtained by using CaCl2 flux of 20∼40 per cent for thoria’s weight and about 25 per cent in excess of the theoretical amount of calcium.
(4) The effeciency of reduction becomes the highest by heating for 4 hr at 950°C or for 3 hr at 1050°C.
Under the above-mentioned conditions, about 90 per cent yield of thorium metal and 3∼7 per cent of residue undissolved with HCl can be obtained.抄録全体を表示PDF形式でダウンロード (606K) -
田村 至1967 年 31 巻 1 号 p. 49-53
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーCr-Vicalloy specimens composed of 12%(Cr+V), 52%Co, balance Fe were air-cooled from 1100°C, reduced to 90% by cold rolling and then subjected to tempering at temperatures between 100° and 800°C.
The changes in the saturation induction, residual induction, coercive force and torque curves have been measured by many workers. The coercive force reaches a maximum (about 300 Oe) by tempering at 500°∼600°C.
The direction of easy magnetization in the rolled state is perpendicular to the rolling surface, and becomes paralled to the rolling direction in the tempered state.
In this case, particulary the changes in microstructure, texture, crystal structure, lattice constant, electrical resistivity, mechanical hardness, Young’s modulus, internal stress were determined. By tempering at about 300°C after cold-working, the gamma phase appears first. The texture of the tempered state is very similar to that of the cold worked state. The former is the sharper. The investigation of the phase by X-rays is indentical to the observation by electron microscope. The lattice constant decreases first by tempering at about 300°C. The electrical resistivity reaches a maximum by tempering at 300°∼400°C and then a minimum by tempering at about 600°C.
The mechanical hardness reaches the maximum by tempering at about 500°C. The internal stress reaches a minimum by tempering at about 400°C and then a maximum by tempering at 500°∼600°C. These are caused by the ordering of the alpha phase and the transformation of the alpha phase to the gamma phase by tempering. The magnetic anisotropy of Cr-containing Vicalloy is not caused by the directional order, but probably by the variation of the direction of easy magnetization during the ordering of the alpha phase by tempering. The coercive force of about 300 Oe is not only caused by a single domain but also by the difficulty of the domain wall displacement.
The above-mentioned conception differs from the various theories in the past.抄録全体を表示PDF形式でダウンロード (2176K) -
下田 秀夫, 石塚 寛, 大西 敬三, 干葉 隆一, 沢田 進1967 年 31 巻 1 号 p. 54-59
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーIn order to determine relationship between the evolution site of hydrogen from steel surface and microstructure in steel, the evolved site of hydrogen from the out-going surface of specimens in the hydrogen permeation test was observed by a microscope. The specimens used are several kinds of air-melted commercial steel plates, and vacuum melted iron and steels. Results of the observation are as follows:
(1) In the commercial steel plates, hydrogen was actively evolved from the non-metallic inclusion, but scarcely evolved from matrix.
(2) In the vacuum-melted materials, hydrogen was evolved from the ferrite grain boundary or primary cementite.
The rate of hydrogen evolution from the grain boundary or cementite was slow compared with that from the non-metallic inclusion.抄録全体を表示PDF形式でダウンロード (1840K) -
塩原 ヤイ1967 年 31 巻 1 号 p. 59-63
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーA combined electrographic-ring oven method has been developed for the determination of nickel and copper in several kinds of coins. The coin is placed on a aluminum rod electrode and covered with a small paper disc which is previously treated with 1 M NH4Cl solution. Putting a pointed counter electrode (alminum) on the paper, an electric current is applied between the two electrodes so that the coin constituents are electrographically stripped into the moistened paper disc. After the copper is fixed by exposing the disc to H2S gas, it is placed on a ring oven heated to 100°C and the nickel is allowed to diffuse out of the disc into a ring zone by dropping 0.05 M HCl solution. The disc is then removed and exposed to bromine vapor to convert the sulfide to the soluble sulfate so that the disc can be again placed on the ring oven system. Copper is washed out into the ring zone by 0.05 M HCl solution as before. Latent rings of nickel and copper are sprayed by dimethylglyoxime and rubeanic acid solution to develop color, respectively. The colored rings are visually compared with a series of standard rings previously prepared with varying amounts of the respective metal ions. The method described is actually nondestructive and reasonably rapid, taking about 10 min to complete the whole procedure. The precision is approximately 1.7% for copper and 5.2% for nickel, affording a sound basis for the rapid determination. A qualitative test for a particular element in coins can also be performed by stripping its coin constituents into the disc by the electrographic technique, washing out a desired constituent into the ring zone and developing color with a proper colorimetric reagent as described above. A detailed procedure for a qualitative electrographic-ring oven method of analysis is given for 8 elements.抄録全体を表示PDF形式でダウンロード (1147K) -
五弓 勇雄, 木原 諄二, 落合 征雄1967 年 31 巻 1 号 p. 63-66
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーRecently the rolling speed of the hot strip mill has become so fast that the strain rate of the rolled specimen reaches 3∼5×102/sec. The strain rate of experimental rolling material, however, is about 10/sec at most. Therefore, it is impossible to investigate in greater details the effect of hot-working and thermal history on texture and mechanical properties, etc. in a laboratory or a factory.
A simulation of hot rolling was tried about 0.05%C-rimmed steel with a “counter-blow type” forging machine. Elongated specimens are compressed under no lubrication at a strain rate of 900/sec, and when the reduction of thickness is about 60%, the hot-worked specimens of 15×15 mm2 deformed under a plain-strain condition can be obtained. From measurements of the low index plane density parallel to the specimen plane, the dependence of the texture on hot-working temperature can be explained from that of the hot-rolled texture. It is concluded that this simulation may be a successful one.抄録全体を表示PDF形式でダウンロード (464K) -
杉本 孝一, 茨木 正雄1967 年 31 巻 1 号 p. 67-72
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーInternal friction measurements were carried out at 20° in a magnetic field up to 600 Oe with polycrystalline pure iron specimens vibrating transversely at strain-amplitudes rangeing from 8.4×10−8 to 1.7×10−5. Using the experimental results, the internal friction was shown in three-dimensional diagrams, which give the relation among internal friction, strain-amplitude and magnetic field, and the following characteristic changes were recognized to be of ferromagnetic origin. The well-defined peak-like behaviour, observed at lower fields than 100 Oe, was confirmed to be due to the magneto-mechanical hysteresis loss caused by the irreversible movement of 90°-domain walls in iron. While the gradual increase in internal friction at higher fields was considered to be the same as reported by T. S. Kê, who proposed a new mechanism of eddv-current loss which is characteric of transversal vibration. Discussion were done with the two types of internal friction compared with the results of some other magnetic measurements (magnetization curves and incremental permeability). It was concluded that in the present experimental conditions there was no internal friction other than of ferromagnetic origin except for the unknown background damping.抄録全体を表示PDF形式でダウンロード (1195K) -
岩田 祐治, 浅山 行昭, 坂本 昭1967 年 31 巻 1 号 p. 73-77
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーThe embrittlement of ultra-high strength steels due to the action of hydrogen introduced by Cd-electroplating has been studied in stress rupture (sustained load) and tensile tests for notched specimens.
4340 steel, SNCM 9, 300 M steel, H-11 Mod. steel and 18%Ni maraging steel, heat-treated to the 200 kg/mm2 tensile strength level, and 5.5W-2.5Cr steel and SKS 4, heat-treated to the 170 kg/mm2 tensile strength level, were examined.
The results of the present work are:
(1) Susceptibility of hydrogen embrittlement estimated by redution of area and notch tensile strength were as follows:
SNCM 9\fallingdotseq4340\gtrsimH-11 Mod.>SKS 4>300 M>18%Ni maraging steel>5.5W-2.5Cr.
(2) Susceptibility of hydrogen embrittlement estimated by delayed failure properties were as follows:
4340\fallingdotseqSNCM 9>300 M>H-11 Mod.\fallingdotseqSKS 4>18%Ni maraging steel\gtrsim5.5-2.5Cr.
(3) 5.5W-2.5Cr steel and 18%Ni maraging steel were noticeably less susceptible to embrittlement by hydrogen than the others.
(4) Of the hydrogen embrittled plain tensile specimens, 5.5W-2.5Cr steel showed cup and cone type fractures similar to the unplated specimen, but others showed brittled fractures whose failure was initiated just below the surface of specimens.
Failure-initiated regions of SNCM 9, 4340 steel, 300 M steel and SKS 4 show the coexistence of intergrannular and transgranular crackings with respect to pre-austenite grain boundaries in away similar to the hydrogen-induced delayed failure, but the interganular cracking was predominant.抄録全体を表示PDF形式でダウンロード (1494K) -
岩田 祐治, 浅山 行昭, 坂本 昭1967 年 31 巻 1 号 p. 77-83
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーThe brittle delayed failure phenomenon of cadmium plated steel which takes place under sustained loading at about 200°∼300°C, below cadmium melting point (321°C), was examined for several high strength steels.
The results of the tests showed that the behavior of the brittle delayed failure was the same as stress-corrosion cracking in liquid metal and depends on the nickel content and toughness of the steels. Also, the behavior was affected by the existence of cadmium oxide between cadmium and steel. This fact suggests that the rupture may be closely related to the vapour pressure of cadmium.
The activation energy for the process was 21800 cal/mol.
The kinetics of crack propagation indicated that cracking progressed in a discontinuous fasion. Embrittled crackings of delayed failure appear to be intergranular with respect to pre-austenite grain boundaries.抄録全体を表示PDF形式でダウンロード (995K) -
五弓 勇雄, 岸 輝雄, 二宮 敬1967 年 31 巻 1 号 p. 83-89
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーThe mechanism of wire-drawing depends on external forces, boundary conditions of the process, and plastic properties of the wire. In the present investigation, we measured the die pressure distribution which is a main boundary condition in wire-drawing. With a new experimental technique, the pin contact method, the measurement of the die pressure distribution for the first time was successfully carried out. The results are as follows:
(1) In the drawing process, the pin projection was changed continuously and when the pin head reached the die surface, the increase of die pressure stopped for a time. From this plateau’s value, the exact die pressure was measured.
(2) The entry of the die approach showed a very high die pressure which is about two times as large as the yield stress, A considerable die pressure, which seemed to satisfy the yield condition, was observed at the center of the die bearing.
(3) Adding the back tension, only the die pressure at the entry of the approach decreased remarkably, and there was no die pressure in the bearing.
(4) A reasonable die pressure distribution was determined from these experimental results. The present investigation has revealed weakness in the existing wire-drawing theories such as a simple method by Sachs, Siebel and Geleji and a slip line method by Hill, Tupper and Pawelski.
Lastly we proposed a theoretical die pressure distribution based on our experimental results.抄録全体を表示PDF形式でダウンロード (1134K) -
依田 連平, 新井 隆1967 年 31 巻 1 号 p. 90-94
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーAs molybdenum which is a typical refractory metal has poor oxidation resistance, but it has high strength at elevated temperatures, it cannot be used at high temperatures in air. We have tried a new coating method to use molybdenum under the above-mentioned condition. According to this new method, commercially-pure molybdenum rods are covered with Nimonic 90 nickel-base alloy which is hot-workable and oxidation-resistant and forge-worked. We named this technique the composite cast-working method.
After the composite cast materials were hot-swaged, they were creep-rupture tested at 1000°C with a stress of 5 to 10 kg/mm2 in air. The results are as follows:
(1) It is possible to work the hard and brittle diffusion zone formed in the interface between molybdenum and the covering alloy without cracking.
(2) It is possible to heat and work molybdenum freely in air, and to make the materials stable by the following working even if the discontinuities in bonding were formed when molybdenum was composite cast with Nimonic 90 alloy.
(3) The creep-rupture strength of the composite cast materials at 1000°C in air is improved to a great extent as the part of the molybdenum core is increased, while the effect on the strength is negligible when the molybdenum core is small.
(4) The creep-rupture strength of these materials depends on the area of both molybdenum and diffusion zones, and the strength for this area is comparable to the strength of molybdenum under the same condition in vacuum. From this result, it is indicated that the new coating method using Nimonic 90 alloy can protect molybdenum perfectly from the oxidation at elevated temperatures in air.抄録全体を表示PDF形式でダウンロード (1089K) -
1967 年 31 巻 1 号 p. 94
発行日: 1967年
公開日: 2008/04/04
ジャーナル フリーPDFを参照． （誤）本誌, 30 (1966),, 溶液含有量, mおよびk0 （正）本誌, 30 (1966), 1068., 溶質含有量, −m(1−k0)抄録全体を表示PDF形式でダウンロード (12K)
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