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Volume 28, Issue 11
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Katashi Masumoto, Shigehiro Isomura1964 Volume 28 Issue 11 Pages 663-670
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSLarge single crystals of a semiconducting an intermetallic compound ZnSnAs2 have been grown by the Bridgman method. This compound crystallizes in either the chalcopyrite structure or the zinc-blende structure. The semiconducting properties of both structures have been studied. The resistivity, Hall coefficient, Seebeck coefficient and infrared absorption have been measured as a function of temperature. Measurements of the Seebeck coefficient and the infrared absorption were made only for the chalcopyrite structure. The results are as follows.
Single crystals of ZnSnAs2 show p-type conductivity and cleave on the (110) plane. For single crystals having the chalcopyrite structure, a hole mobility of 130 cm2/V·sec and a carrier concentration of 1.2×1018/cm3 are observed at room temperature. The width of the forbidden energy gap for indirect transitions at 0°K of 0.59 eV is obtained from a slope of the intrinsic resistivity curve. The mobility ratios found by the usual procedure from the Hall coefficient maximum and determined from the resistivity data by the method derived by Hunter are 9 and 12, respectively. From the Seebeck coefficient data, the effective mass of holes is calculated to vary from 0.43 m0 at 296°K to 59 m0 at 557°K, and the relaxation time is found to be 2.6×10−14 sec at 296°K. The infrared absorption gives a value of 0.66 eV for the energy gap for direct transitions at room temperature and measurements over the temperature range from 88°K to 296°K suggest that the energy gap is about 0.74 eV at 0°K. For the disordered zinc-blende structure, a resistivity of the order of the 10−3 ohm-cm and a carrier concentration of the order of 1019/cm3 are shown at room temperature.View full abstractDownload PDF (1026K) -
Tetsuya Takaai1964 Volume 28 Issue 11 Pages 670-676
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe electron beam melting and brittle fracture behaviour of metal molybdenum has been studied using a 60 KW electron beam melting furnace, a Tensilon testing machine, a Charpy impact testing machine and the X-ray Laue back reflection procedure. The crystal grains of electron beam melted molybdenum were extraordinally large in size and thick, and about 100 mm long columnar grains were observed in a 30 mm dia ingot. These grains, which grew columnar-like, had a certain degree of orientation preference.
The metal molybdenum in the as cast state exhibited a typical brittleness and the fractured surfaces were principally grain boundaries except cleavage fractures of (100) planes as shown by the X-ray back reflection results.
According to the spectrographic analysis, the volatile metallic impurities were volatilized preferentially as expected from their vapour pressure data. On the other hand, those metallic impurities, which have relatively higher melting points and lower vapour pressures, were rather rich in melted molybdenum. Although C, O and N were not analysed, the tensile stress-strain-diagram of an electron beam melted molybdenum wire showed almost no yielding behaviour. Therefore, the present author assumed that the electron beam melted molybdenum had the least amount of interstitial impurities. The brittle fracture strength was remarkably increased with frequency of the melting operation.View full abstractDownload PDF (1265K) -
Tetsuya Takaai1964 Volume 28 Issue 11 Pages 676-683
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe grain boundary inclusions of electron beam melted molybdenum were studied by fractographic method using electron and optical microscope. A great many fine precipitates were found in the fractured boundaries. These boundary inclusions substantially decreased and became small in size substantially with frequency of the melting operation from one to 5 times. and hardly observable by optical microscope. But the brittle fracture still occurred at grain bound aries and a good many fine precipitates of 0.2∼0.3 micron in size were also found by an electron microscope. The lattice spacings of the extracted boundary inclusions were determined to be molybdenum carbide Mo2C. Those specimens, contain a good many inclusions, were heated in vacuum at 1500°∼2000°C, 2∼1×10−4 mmHg for 1 hr. But the inclusions did not change substantially and the diffracted patterns were identical with those of the initial specimens.
The grain boundary surfaces of those specimens which were pretreated in hydrogen flow and then electron beam melted were fine and clear, and the boundary inclusions were smaller than the non-treated. On the other hand, the electron beam melted molybdenum with carbon additions had very fine crystal grains and fractured mainly trans-granularly, but the fractures in grain boundaries were hardly observable. The electron diffraction test showed that those boundary inclusions in carbon added molybdenum were also molybdenum carbide Mo2C. And thus, the present author could not find any oxide diffraction patterns from the extracted grain boundary inclusions.View full abstractDownload PDF (1180K) -
Tatsuo Maekawa, Nobuo Nakajima1964 Volume 28 Issue 11 Pages 684-688
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAnodic behaviors of pure iron and its oxides in acid and alkaline solutions were investigated to clarify the significance of passivation potential and other oxidizing potential of iron. The anodic polarization curve of pure iron indicated four current peaks at the potentials of about −0.1, 0.3, 0.6 and 1.4 V in 1 N H2SO4, and −0.9, −0.8, −0.4 and 0∼0.4 V (vs S.C.E.) in 1 N KOH, respectively. The anodic polarization curves of FeO1.05, FeO1.1 and Fe3O4 indicated three, two and one peaks, respectively. And the potentials of the peaks of the oxides agreed with those of pure iron. From these anodic behaviors of oxides, it was suggested that the four potentials at the current peaks in the potential-current curve show four redox potentials of Fe/FeO1.05, FeO1.05/FeO1.1, FeO1.1/Fe3O4, and Fe3O4/Fe2O3. These potentials were also confirmed from the measurements of potential decay curves of iron and its oxides. It was concluded that the passivation potential of iron in 1 N H2SO4 solution corresponded with the redox potential of FeO1.05/FeO1.1, where as the passivation potential in 1 N KOH solution corresponded with the redox potential of Fe/FeO1.05 or FeO1.05/FeO1.1.View full abstractDownload PDF (1001K) -
Effect of the Aluminum Content on the Low Temperature Treatment of an Al-Ni-Co Type Permanent MagnetYuki Shirakawa, Daiji Amemiya, Takeshi Abe1964 Volume 28 Issue 11 Pages 689-692
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn a previous paper it was found that the magnetic properties of Alnico type N.K.S.-1F permanent magnet showed anomaly at about 875°C, and the maximum energy product of magnet thus treated was the same as or better than that by the high temperature treatment. In this paper, the variation in the temperature of the low temperature treatment was measured with a series of magnet alloys containing various Al contents 6 to 10%. The experiments showed that the temperature of low temperature treatment increased with the Al content and the rate of variation was about 67.6°C per unit % of Al.
At the same time the Curie points of these magnets were measured. The Curie points A2 were found to be almost constant except in the case of a high Al content, and A2 coincided with the optimum temperature of low temperature treatment TL in the standard composition of 8%Al at which the magnetic properties were most satisfactory, while it was lower than TL with a higher Al content and higher with a lower Al content. This suggests that the effect of the low temperature treatment is the most excellent as the difference of A2 and TL is the smallest.View full abstractDownload PDF (914K) -
Akio Yamaguchi, Joichiro Moriyama1964 Volume 28 Issue 11 Pages 692-697
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe kinetics of hydrogen reduction of NiO fine powders were investigated at temperatures of 200° to 250°C and at the hydrogen pressure of 1 atm, furthermore by means of Delmon’s interruption method at temperature of 215°∼260°C. The shapes of the reaction curves obtained from the former experiments were of the Sigmoid type. Their kinetic equations were expressed as
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The apparent activation energy for the initial period was 23.4 kcal/mol, for the principal period 25.6 kcal/mol and for the final period 23.4 kcal/mol. When investigated the sample prereduced to 25∼30% at 230°C by the interruption method, the activation energy for the advance rate of reaction interface was 31.6 kcal/mol. The date obtained indicate that the reduction rate in principal period is affected by the experimental condition of the initial period. From the present experimental results, the reaction mechanism is discussed.View full abstractDownload PDF (920K) -
Teizo Aida1964 Volume 28 Issue 11 Pages 698-704
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe silver-cadmium oxide electric contact is being used for a circuit with a medium or heavy load because of the high electrical conductivity and excellent welding resistance. In addition, good arc charactristics are also required for small type circuit breakers and medium load relays. Therefore, the welding charactristics of Ag-CdO sintered alloys prepared from mixed Ag-CdO electrolytic powder and mixed precipitates were investigated by the welding test at static contact, and the arc duration time at breaking contact was also measured.
The results newly obtained are as follows:
(1) The welding resistance gradually increases with a higher CdO concentration, and shows the maximum value at the composition of about 88Ag-12CdO.
(2) The arc duration time becomes longer with increases of the CdO concentration, CdO particle size, applied voltage and the circuit current.
From the above observations it is assumed that the cadmium oxide is dissociated at a temperature higher than 900°C and the dissociated Cd atoms, the ionizated Cd ions, etc. that modulate the arcing atomsphere have an unfavorable effect on the arc duration charactristics.View full abstractDownload PDF (979K) -
Toshimitsu Uto, Hyoma Kitajima, Toshio Kai1964 Volume 28 Issue 11 Pages 704-710
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThis research has been carried out to improve the corrosion resistance of Fe-Ni-Si alloys by means of examining the influence of copper added to Fe-Ni-Si alloys.
Following are the results of investigation on 20 kinds of alloys containing 3∼15%Cu, with regard to the transverse breaking load, deflection, hardness, micro-structure, X-ray difraction, and corrosion resistance against sulfuric acid and hydrochloric acid.
(1) The transverse breaking load and deflection decrease gradually with the increasing addition of Cu, and even the addition of 15%Cu retains a strength equivalent to the Hasetelloy D alloy.
(2) The corrosion resistance is much improved by the Cu addition, and this effect is particularly remarkable against the sulfuric acid. Namely the Fe-Ni-Si-Cu alloy is usable for 20∼40% sulfuric acid any temperature up to the boiling point and for any concentration between 0∼85%, if the temperature is below 80°C. The corrosion resistance is found to be 2∼10 times as large as that of Fe-Ni-Si alloys. Also the alloy can be used for hydrochloric acid of 0∼20% concentration at the temperatures up to 40°C.View full abstractDownload PDF (1112K) -
Genjiro Mima, Masaharu Yamaguchi1964 Volume 28 Issue 11 Pages 710-716
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIsothermal softening of the cold drawn aluminium-2 wt% magnesium alloy has been studied by the tensile test and microscopic examination. The isothermal annealing treatment of the specimen was carried out in the temperature range of 164°∼340°C.
It is shown that the step-wise softening is a common occurrence during annealing at a temperature lower than about 300°C and number of the steps increase with decreasing annealing temperature at a constant cold reduction. It is also found that the percentage softening brought about by the proceeding steps before the primary recrystallization step is about 10∼40%. The steps proceeding before the primary recrystallization show no marked recovery in elongation.
The structure changes corresponding to the steps before the primary recrystallization step are also detectable by a optical microscopic observation.
In this paper the primary recrystallization means the formation of new recrystallized grains and a marked recovery of elongation by annealing plastically deformed material. For the primary recrystallization step, the activation energies are found to be 40∼50 kcal/mol, while 20∼30 kcal/mol for the steps before the primary recrystallization.View full abstractDownload PDF (1407K) -
Seita Sakui, Tsutomu Mori, Masahiro Higuchi1964 Volume 28 Issue 11 Pages 717-721
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe lower yield stress and flow stress of 0.03%C and 0.0044%N iron were determined by dynamic tensile test and static test at room temperature and −78°C. From the grain size dependence of the yield stress and flow stress, σ=σi+kd−1⁄2, it was concluded that the strong dependences of the yield stress and flow stress on strain rate and temperature were due to those of frictional stress σi. Further, it was found that the strain rate and temperature dependence of σi had no relation to the amount of prestrain. From the abve observation and the insensitivity of the strain rate and temperature dependence of σi to the amount of interstitial impurities (first report), it was concluded that the Peierls-Nabarro stress is important to the large value of σi and its strong strain rate and temperature dependence in iron.View full abstractDownload PDF (698K) -
Susumu Morioka, Minoru Takahashi, Yoshinobu Sawada, Yasuro Watanabe1964 Volume 28 Issue 11 Pages 722-727
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of heat-treatment on the magnetic properties of electrodeposited Permalloy films were studied.
Copper plates used as substrates were polished by a buffer. The specimens, 5×5 mm with or without substrates were used for the heat-treatment. The specimens were subjected to vacuum annealing in a non-magnetic field or in a magnetic field perpendicular to the polishing scratches.
The changes of the magnetic properties before and after annealing were measured by a 50 cps B-H loop tracer. Before annealing these films had magnetic anisotropic properties and their most easy direction was along the polishing scratches.
In the case of films with substrates, Hc decreased with the annealing temperature up to 350°C either in the magnetic field or non-magnetic field, but at temperatures above 350°C it increased and Bs decreased greatly due to the alloying effect. In the case of films without substrates, on the other hand, Hc decreased up to 600°C, Bs was almost constant and the magnetic anisotropy caused by the polishing scratches disappeared.
The effect of annealing in a magnetic field were observed at temperatures above 400°C reaching a maximum at 475°C at which the easy axis coincided with the direction of the applied field during annealing.View full abstractDownload PDF (762K) -
Sakae Takeuchi, Osamu Watanabe1964 Volume 28 Issue 11 Pages 728-734
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe crystallographic aspect of hexagonal titanium crystals grown by electro-refining from molten salt was examined. The crystals reveal various shapes (plates, needles, dendrites) depending upon the conditions of electrolysis such as the bath composition, the purity of the salt, the cathode current density and the temperature of electrolysis. When the crystals were grown from high purity salt, the crystal were bounded by the basal plane and planes of {10\bar12}, {10\bar13}, {10\bar14}, {10\bar11}, while the crystals from impure salt were bounded by the basal plane and planes of {30\bar31}, {30\bar32}, etc. At a relatively high temperature and low current density the crystals were grown in plates parallel to the basal plane. At low temperature or high current density the crystals were grown in needles parallel to ⟨10\bar11⟩, ⟨11\bar22⟩ and ⟨10\bar13⟩. Growth twins were observed frequently. The twining planes were {10\bar11}, {10\bar12} and {11\bar21}. The planes of this type have not been previously reported for deformation twins.View full abstractDownload PDF (1230K) -
Kazutomo Oyama, Sadao Watanabe, Osamu Izumi1964 Volume 28 Issue 11 Pages 735-739
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe characteristics of cold impact extrusion of Al were investigated using the high-energy rate metal forming machine “DYNAPAK-Model 600”, the maximum ram-velocity of more than 20 m/sec was attained by the use of high-pressure nitrogen-gas as a driving source. The results were compared with those of slow-rate extrusion using a 500-ton hydraulic press (about 0.6 mm/sec). Remarkable differences were observed between them, for instance, on the behaviours of lubrication, metal-flows and hardness distribution.
Especially, with the DYNAPAK extrusion, the heat-generation due to adiabatic deformation and the inertial pull-force due to deceleration of ram-velocity show marked effects on the mechanical properties or shapes of the extruded rods: the former results in partial softening and the latter sometimes causes inertial parting.View full abstractDownload PDF (734K) -
Kazutomo Oyama, Hiromi Tokuno, Osamu Izumi1964 Volume 28 Issue 11 Pages 740-745
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSUsing the high-energy rate metal forming machine “DYNAPAK-Model 600” (maximum ram velocity: about 20 m/sec) and a 30-ton testing machine (2 mm/min), the impact and slow-rate extrusion behaviours of Al at elevated temperatures (250°∼550°C) were examined. The hot impact extrusion, compared with the slow-rate one, was characterized as follows. The work required for extrusion increased about three times, and the maximum punch load to the elevated temperature did not decrease so much.
The relation between punch-load (P) and extrusion-ratio (R) is expressed as P=A·Rn, where A and n are constants. The heat-generation due to adiabatic deformation recrystallized the hot-extruded rods completely. However, the region of residual billet was not recrystallized and showed a slightly higher hardness value than that of the slow-rate extrusion.View full abstractDownload PDF (1353K) -
Kuniyoshi Watai, Shotaro Shimizu, Yasunobu Tsuji1964 Volume 28 Issue 11 Pages 745-749
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAlloys containing Pd substituted for Pt in Pt-Co alloys with equiatomic composition were prepared by powder metallurgy. The lattice transition temperature was obtained from the variation of saturation magnetization, and magnetic transition temperature was measured by a magnetic balance. The filing powder was prepared for X-ray diffraction analysis, and the electrical resistivity was measured using a thin wire drawn to 0.2 mmφ. Some of the alloys were heat-treated under various conditions, and their permanent magnetic properties were measured. The results are summarized as follows:
(1) When Pd was substituted for Pt, the lattice transition temperature decended, while the magnetic transition temperature ascended. But no alloys were obtained on which some effect of heat-treatments in the magnetic field could be expected.
(2) The axial ratio of the superlattice progressively approached unity with the addition of Pd, and the formation of superlattice was suppressed in alloys containing more than 10 at%Pd.
(3) The rate of lattice transition was delayed by addition of Pd. Consequently, a higher temperature and a longer time were required for the heat-treatment to obtain the best permanent magnetic properties, by which the stability at a high temperature was improved.
(4) An energy product higher than 10.0×106 G·Oe, with improved reproducibility, was obtained from alloys containing 2∼5 at%Pd.View full abstractDownload PDF (797K) -
Tadayuki Nakayama, Tatsuya Koizumi1964 Volume 28 Issue 11 Pages 749-754
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe present authors have studied the structures of oxide films produced on Ti surfaces by dry and wet oxidation. The following results were obtained by transmission and reflection electron diffraction. (1) The dry oxidation films produced on Ti surface in air at 400°C for 5 min consisted of only rutile type crystals. (2) The wet oxidation films formed on Ti in boiling concHNO3 for 4 hr and 24 hr were found to take double layer structures composed of outer anatase and inner rutile layers, and the rutile layer grew with the immersing time. (3) Ti quenched in water after heating in air at 500°C for 3 min was covered with oxide layers composed of rutile and anatase, while only rutile crystals were detected in the oxide films which were formed on Ti quenched in oil after heating in air under the same conditions. (4) The oxide films formed on Ti hydride surface by heating in air at 300°C consisted of only rutile crystals, while both rutile and anatase crystals were found in the oxide films produced on Ti hydride surface by heating in air at 350°, 400°, 450° and 500°C. (5) The diffraction pattern of meta titanic acid (TiO2·H2O) obtained by hydrolysis of TiCl4 was found to be the same pattern as anatase type TiO2 crystal.
The above results suggest that anatase type oxide detected in wet oxidation films would be hydrated oxide of Ti resembling meta titanic acid.View full abstractDownload PDF (1356K) -
Yoshimi Tanabe, Kyoko Fujii1964 Volume 28 Issue 11 Pages 754-758
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this paper, as the first step of study on the removal of zinc in open hearth dust by chloridizing roasting with a fluidized bed, the possibility of a fluidization of dust was investigated, and then the elutriation velocity constant and the average residence time were measured by means of the batch type fluidized bed. The results obtained were as follows:
(1) A fluidization of dust occurred by mixing dust with powdered iron ore.
(2) The elutriation velocity constant was proportional to about 2.5 power of the fluid velocity.
(3) In the absence of overflow, the average residence time was 7 min at the fluid velocity of 100 cm/sec and 1700 min at the fluid velocity of 10 cm/sec.View full abstractDownload PDF (554K) -
Takehiko Kawaguchi, Yasuo Kudo, Toshiyuki Tokuda1964 Volume 28 Issue 11 Pages 759-763
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSGenerally, a relatively small amount of the element boron is added to steel for the purpose of increasing the hardenability of steel. Quantitative spectrographic analysis with the point-to-plane technique was attempted to determine the microamount of boron in steel. In this experiment, it was found that (1) BI 2497.733 Å was interfered with FeII 2497.717 Å in case of exciting a sample by multi-source unit; (2) the maximum detectability of boron was obtained when a sample was excited by d.c. arc and its polarity was positive; (3) the detectability and precision of analysis were increased by the superimpose exposure technique; and (4) the size and form of unknown samples were desirable to be processed to those of standard samples as much as possible, since the effects of the volume of samples on the analytical value were significant. The final spectrographic conditions and results are as follows.
The samples were excited by d.c. arc at 5 amp. using carbon rods as counter electrode. The analytical line was BI 2497.733 Å, and FeI 2494.250 Å or Fe 2485.985 Å was used as an internal standard line. The coefficient of variation of the method was about 10% at 1∼100 p.p.m. boron.View full abstractDownload PDF (1092K) -
Hidehiro Goto, Shigero Ikeda, Minoru Hosoya1964 Volume 28 Issue 11 Pages 764-767
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAn apparatus for the rapid determination of hydrogen in iron and steel was constructed by applying the argon carrier gas hot extraction technique.
The steel sample was heated at 950°∼1100°C in the stream of argon, purified by passing through hot titanium sponge and P2O5.
Hydrogen extracted from the sample was carried into the palladium spiral tube. Here, the whole of the hydrogen diffused into the evacuated part surrounding the palladium spiral and collected by a mercury diffusion pump and an automatic toepler pump in the gas collector connected with a cappirary manometer, by which the amount of hydrogen was determined from the mercury height.
This method was applied for the determination of hydrogen in iron, steel and cast iron, and the hydrogen concentration higher than 0.00001% was determined with good reproducibility within 25 min.View full abstractDownload PDF (457K) -
Yoshio Baba, Toshio Amitani, Shiro Terai1964 Volume 28 Issue 11 Pages 768-773
Published: 1964
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSLately, the colored anodizing aluminium alloys have often been used as the building materials. As a study on the brown anodizable Al-Cr-Mn alloys, the present experiments were carried out to investigate the relation among the color of oxide film after anodizing in sulfuric acid solution, the contents of Cr and Mn added to Al alloys of various purities and the heat treatment.
The results obtained are as follows:
Al-Cr-Mn alloys containing of Cr≥0.2∼0.3% and Mn≥0.2∼0.3% show brown or bronze color after the anodizing treatment in the single phase state. In this case the brown color became clearer with the Cr and Mn contents, but the alloys present black color when large amounts of the intermetallic compounds of Al-Cr-Mn precipitated from the super saturated solid solution of the alloys. This might be attributed to the light of incidence which are absorbed or scattered by these compounds retained in the oxide film after anodizing.
Al-Cr-Mn alloys produced by the aluminium of lower purity show a dull brown color after anodizing, because the impurities facilitate the precipitation of Cr and Mn and also cause the scattering of the light of incidence.View full abstractDownload PDF (1122K)
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