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Volume 39, Issue 4
Displaying 1-17 of 17 articles from this issue
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Keijiro Nakasa, Hideo Takei, Tetsuhiro Asamoto1975 Volume 39 Issue 4 Pages 327-333
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of delayed failure phenomenon on fatigue crack initiation in water was investigated with notched specimen of high strength Ni-Cr-Mo steel (JIS: SNCM 8). The results obtained are as follows:
(1) The number of cycles at fatigue crack initiation (N) depends on the range of apparent stress intensity factor (ΔKa) regardless of the notch length, when the ratio of the mean value of repeating apparent stress intensity factor (Kam) to ΔKa and the notch root radius (ρ) are constant.
(2) When Kam⁄ΔKa and ρ are constant, the number of cycles at fatigue crack initiation (N) in water is less than that in air as the frequency or ΔKa decreases. The shape of ΔKa-N curve in water varies with Kam⁄ΔKa and frequency. Sometimes two bulged parts are observed on the ΔKa-N curves in water, and the upper one at short fatigue life suggests the existence of a strong effect of the delayed failure phenomenon on the fatigue crack initiation in water.View full abstractDownload PDF (582K) -
Masakazu Sakaguchi, Takakuni Hirabayashi, Masatoshi Ota1975 Volume 39 Issue 4 Pages 333-338
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe carburizing of steel by the gases produced by the pyrolysis of the powdered Prussian blue was investigated using 14C as a tracer.
The carburizing was carried out for 10∼120 min in the temperature range of 500 to 800°C by use of a static apparatus connected to a high vacuum line.
The amount of carburization on the surface layer of steel showed a maximum when the carburizing was carried out at about 700°C. At a lower temperature it increased slightly with the carburizing time, while at a higher temperature it increased initially but decreased considerably with the carburizing time. The depth of carbon penetration was several microns at low temperature (600°C) and proceeded no less than several tens microns at high temperature (800°C). The composition of the gases produced by the pyrolysis of Prussian blue was determined by infrared spectrophotometry. From the result, it was found that the effective gaseous materials for the carburizing were HCN at lower temperatures (400∼600°C) and CO and CH4 at higher temperatures (600∼800°C). Furthermore, in an atmosphere of NH3 or H2, the carburizing was promoted by the enhancement of the formation of CH4, but it was retarded in O2 with the formation of CO2 which was a decarburizing agent.View full abstractDownload PDF (479K) -
Naotsugu Inakazu, Hisashi Yamamoto1975 Volume 39 Issue 4 Pages 339-345
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to find the correlation between the torsion fatigue strength and the process of fiber texture changes in drawn aluminium wire, measurements of fatigue strength were carried out on the wires of various drawing ratios, and the orientation changes during fatigue were investigated by means of X-ray pole figure determination.
It was found that the orientation {112}⟨111⟩ developed by drawing up to a reduction of approximately 72 per cent and the orientation near {110}⟨111⟩ developed by drawing up to approximately 82 per cent were the stable orientations for the torsion fatigue.
The ⟨111⟩ single fiber texture developed by drawing up to approximately 93 per cent was accompanied with the stable orientations {110}⟨111⟩ and {112}⟨111⟩.
It was shown that all the orientations were accompanied with the stable end orientation {110}⟨111⟩ except for the orientations {112}⟨111⟩ and {001}⟨100⟩.
From a consideration of the torsion fatigue properties, it was concluded that the specimen drawn by a reduction in area up to approximately 82 per cent, had the highest endurance limit.
Therefore, the wire, in which the ⟨100⟩ fiber component decreases and the stable end orientation {110}⟨111⟩ is developed during fatigue, is expected to be a better material with torsion fatigue resistivity.View full abstractDownload PDF (566K) -
Kazuo Hosokawa1975 Volume 39 Issue 4 Pages 345-351
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWith the aim of obtaining a siliconized layer without any porosity, a silico-carburizing method using a hot bath consisting of Si, carbonate (K2CO3, Na2CO3, Li2CO3, SrCO3 or BaCO3) and neutral salts (KCl, NaCl) has been studied. The results obtained are summarized as follows.
(1) In a hot bath consisting of neutral salts and Si, a thin siliconized layer is formed on the surfaces of iron and steel. In the case of SiC and neutral salts, both siliconizing and carburizing are observed.
(2) In a hot bath consisting of Si, carbonate and neutral salts, siliconized layers are formed on the surfaces of iron and steel and carburized layers beneath them. The siliconized layers are somewhat porous. Impregnation with carbon takes place according to the following reaction:
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The remainder of Si results in the formation of a siliconized layer. The impregnation with silicon seems to be promoted by MO.
(3) The simultaneous impregnation is satisfied most effectively by using a hot bath of 15%Si, 10%Na2CO3, 25%K2CO3, 25%KCl, and 25%NaCl. Silicon concentration in the siliconized layer is analyzed by E.P.M.A. to have a composition gradient from 12 to 6%.View full abstractDownload PDF (865K) -
Hideki Tonda, Takushi Gotoh, Yuusei Nakashima, Tatsuo Kawasaki1975 Volume 39 Issue 4 Pages 351-357
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSFour etchants revealing both fresh and old dislocations as etch pits in zinc (99.999%) crystals were developed. (1) G solution: The chemical composition by volume is 190 parts CH3COOH, 10 parts 35%H2O2, 1∼2 parts 36%HCl, and 50 parts H2O. This etchant produced etch pits with rhombic shapes and those with arrowhead-like shapes on {2\bar1\bar10} and {3\bar2\bar10} surfaces, respectively. (2) K solution: The composition is 95 parts HCOOH and 5 parts 35%H2O2. Etch pits developed on {2\bar1\bar10} surfaces in this solution were rectangular. (3) N solution: The composition is 40 parts CH3COOH, 10 parts 35%H2O2, one part 36%HCl, and 20∼40 parts H2O. This produced two kinds of etch pits on {10\bar10} surfaces, that is, light (rectangular) and dark (lenticular) pits corresponding probably to basal and non-basal dislocations, respectively. The addition of a small amount of FeCl3·6H2O, surfactants, etc. to N solution modified the shape of etch pits. (4) T solution: The composition is 10∼30 parts CH3COOH, 10∼30 parts 35%H2O2, 1∼3 parts 36%HCl, and 1000 parts H2O. This yielded etch-pits or-grooves on {0001} surfaces corresponding to non-basal dislocations.View full abstractDownload PDF (1117K) -
Nobuhiro Iguchi, Yoshiki Oka, Yasunori Saotome1975 Volume 39 Issue 4 Pages 357-361
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe transformation superplasticity occurs depending not on the factor of micro-fine structure required in the micro-grained superplasticity but on the factor of the transformation proceeding under the applied stress. In this report the effects of heating rates upon the transformation superplasticity generated during the ithothermal process were investigated in the low carbon steels with the same method done for pure iron in the previous paper.
The main results obtained are as follows.
(1) The transformation superplasticity in the low carbon steels occurred in the range of 750 to 1050°C under rapid heating (the heating rate: 35∼100°C/sec).
(2) The linear law between the applied stress τ and the total strain γ per cycle was recognized within τ=0.6 kg/mm.
(3) The flow curves induced by the transformation superplasticity were determined at each heating rate. The value of the strain rate sensibility m was about 1.
(4) The transformation superplasticity was not observed in the A1∼A3 point (α+γ) region during the isothermal process.View full abstractDownload PDF (423K) -
Hirobumi Inoue, Katsuhiko Serata, Masanori Tokuda, Masayasu Ohtani1975 Volume 39 Issue 4 Pages 362-367
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSNew analytical method for the study of electrochemical kinetics has been applied to the slag-metal system at high temperature.
By comparing with previous analytical methods for the electrode reaction, this method has shown that the phenomena in the electrode reaction at the slag-metal interface are more accurately and reasonably interpreted.
By analyzing current-time curves obtained by the potential step method, kinetic parameters were derived from an exact solution of the electrode kinetic equation using Deming’s least squares method.View full abstractDownload PDF (461K) -
Morimasa Saito, Emiko Sudo1975 Volume 39 Issue 4 Pages 368-373
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe determination of oxygen in metallic manganese and high-purity aluminium has been made by the vacuum fusion method with a carbon chip-tin-nickel foil bath, the method being effective for the determination of oxygen in metals which involve violent evaporation and are difficult to react with carbon.
In manganese, samples polished chemically and wrapped with a nickel foil (Mn:Ni foil=1∼2:2) was dropped in the crucible at 900°C and then the temperature was raised to 1550°C at the rate of 100°C/min and gases were extracted for 2 min. The oxygen extraction rate by this method was higher than those by the cupper bath and nickel-tin bath methods. The recovery of oxygen by this method was 97∼100 (%) in the known amount of manganese oxide and the deviation coefficient was within 6.6 (%) for electrolytic manganese.
In aluminium, comparison of various bath methods indicated that the above-mentioned method and the iron-tin, copper and nickel-tin bath methods gave inaccurate results with incomplete extraction. By the addition of silicon to the carbon chip-tin-nickel foil bath, the oxygen extraction was increased and the results of determination were in good agreement with those by the fast neutron activation method. Samples electropolished and wrapped with a nickel foil was plunged in the crucible at 1400°C after the addition of 0.1 g of slicon and then the temperature was raised to 1800°C at the rate of 100°C/min and gases were extracted for 3 min.View full abstractDownload PDF (519K) -
Taiji Sohmura, F. Eiichi Fujita1975 Volume 39 Issue 4 Pages 374-380
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe behavior of hydrogen in austenitic stainless steels with different Ni contents, SUS 27, SUS 32 and SUS 42, is studied by means of the 57Fe Mössbauer effect. By the electrolytic hydrogenation, Mössbauer spectra of these stainless steels show asymmetric tails, broadening, and positive isomer shift. The patterns are analyzed and two main spectral components are obtained. One is from the γ phase iron not affected by hydrogen, and the other is from the iron atoms which are affected by surrounding interstitial hydrogen atoms. The latter shows a positive isomer shift relative to the former and its absorption intensity increases with increasing Ni content. Computer analysis show the two-component distribution of the isomer shift more precisely and qualitatively and, in addition, exhibits a small third component which may arise from iron-nickel hydride. The observed positive isomer shift might be interpreted in such a way that the 3d holes of iron are partially filled by the 1s electrons from solute hydrogen and there by the electron density at the nuclei is reduced or that the lattice expansion due to hydrogenation decreases the conduction electron density as a whole. The calculation using the experimental data concerning the high pressure effect on the isomer shift and that of the observed lattice parameter change by hydrogenation shows that the lattice expansion is not always sufficient to interprete the observed isomer shift.
The martensitic transformation of the low Ni austenitic stainless steel, SUS 39, is also studied. Additional broad and ferromagnetic pattern, arising from the α phase has an internal field of about 260 kOe at room temperature. The amount of the α phase increases linearly with the charging time up to 20 hr. This result suggests that the transformation advances into the inside of the specimen with a constant speed.View full abstractDownload PDF (578K) -
Masamichi Kowaka, Masaaki Kitamura1975 Volume 39 Issue 4 Pages 381-387
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of heat treatment on stress corrosion cracking of mild steels in boiling 34%NaOH solution at 124°C has been investigated. The results obtained are as follows:
(1) The susceptibility of intergranular stress corrosion cracking increases with lowering carbon content in steels. Pure iron containing 0.009% carbon still suffered from stress corrosion cracking in boiling 34%NaOH solution.
(2) Mild steels tempered at temperatures between Ac1 and Ac3 for 1 hr and air cooled were resistant to stress corrosion cracking in caustic solution.
(3) The holding time in the (α+γ) range, pre-treatment, and cooling rate from the above temperatures have no noticeable influence on stress corrosion cracking in caustic solution.
(4) The spherdization makes mild steels much more sensitive to stress corrosion cracking than normalized condition.
(5) The stress corrosion cracking of mild steel in caustic solution depends on both the amount of carbon and the distribution of carbide in grain boundaries.View full abstractDownload PDF (1407K) -
Masahiro Ashizuka, Keiz\={o} \={O}e1975 Volume 39 Issue 4 Pages 388-393
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe capacitance of platinum electrode in Na2O-SiO2 melts was measured by the alternating current bridge method in order to obtain the information on slag-metal interfacal structure.
The results obtained are as follows:
(1) Capacitance-potential curves measured by various frequencies (0.2∼2.0 kHz) have the maximum capacitance in the vicinity of −200∼−300 mV (vs Pt) and two minimum capacitances on both sides of the maximum capacitance, and abruptly rose above 200 mV on the anodic side and under −400∼−500 mV on the cathodic side.
(2) The capacitance-potential curve obtained by extrapolating to infinite frequency is parabolic with a hump at the natural electrode potential.
(3) Oxygen ion in melts is adsorbed on to the platinum electrode surface in the vicinity of the natural electrode potential indicating the minimum capacitance on the anodic side for various frequencies.
(4) Adsorption-desorption reaction of oxygen ion occurs in the vicinity of the potential indicating the maximum capacitance (−300∼−450 mV).
(5) The platinum surface is stripped by oxygen ion over the range of −300 to −450 mV and is occuppied by Na+ ion.
(6) The minimum capacitance extrapolated to infinite frequency and the maximum capacitance for several frequencies increase with increasing concentration of Na2O in slag.View full abstractDownload PDF (433K) -
Shozo Yoshioka, Mitsuo Mera, Kenji Morii1975 Volume 39 Issue 4 Pages 394-402
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe deformation behavior and the orientation change during rolling of the single crystals of Cu-10 wt%Zn (Ms-10) and Cu-30 wt%Zn (Ms-30) alloys which have initially the (513)[\bar121] orientation and the orientations near to it have been studied by means of optical microscopy and reflection electron diffraction technique. It was clarified that the (513)[\bar121] orientation which is stable during rolling of the pure copper single crystal was less stable in the case of rolling of α-brass single crystals, and this would be due to the effect of alloying. The results are summarized as follows:
(1) In the Ms-10 crystal and the Ms-30 crystal that did not accompany twinning deformation upon rolling (whether or not Ms-30 crystals accompanies twinning deformation upon rolling, depends on the initial orientations), the lattice rotation about the rolling direction occurred, giving rise to the (101)[\bar121] orientation. This change of orientation is explained well in terms of the slip deformation in the (513)[\bar121] crystal during rolling. It is considered that the lower stability about the rolling direction of the (513)[\bar121] orientation in α-brass may be related to the dynamic recovery during deformation being depressed with the decrease in stacking fault energy due to alloying effect.
(2) In the Ms-30 crystal that caused twinning upon rolling, the (111)[\bar110]+(111)[1\bar10] orientations were attained accompanying the formation of the banded regions of inhomogeneous deformation (shear bands) and retained up to high reductions. Such change of orientation and the stabilization of this orientation are understood in view of the operation of the shear bands during rolling of the (513)[\bar121] crystal containing twin lamellae. According to transmission electron microscopy of the rolled Ms-30 crystal, it was revealed that the microstructures inside the shear bands consist of fine-crystalline aggregates.View full abstractDownload PDF (1460K) -
Masuo Hagiwara, Jun-ichi Seki, Tomoo Suzuki1975 Volume 39 Issue 4 Pages 402-408
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe CsCl-type superlattice formation and the composition dependence of the order-disorder transition temperature (Tc) in V-Mn-Fe, Fe-V-Cr and V-Mn-Cr ternary alloys have been investigated by means of X-ray and differential thermal analysis. The results are summarized as follows.
(1) The Tc of the VMn superlattice is raised by the addition of Fe and is lowered by the addition of Cr.
(2) The Tc of the CsCl-type FeV superlattice is not known because of the intervention of the stable σ-phase. However, it has been found that the Tc can be detected by the addition of Cr which suppresses the formation of the σ-phase. The Tc decreases with the increase of Cr content.
(3) By extrapolating the measured Tc in V-Mn-Fe and Fe-V-Cr ternary alloys, the Tc of the equiatomic FeV superlattice has been estimated to be 850∼880°C.
(4) An anomaly similar to the “550°C anomaly” in α-FeCo and the “730°C anomaly” in δ-VMn has been considered to exist in the disordering process of the FeV superlattice.
(5) Based upon the measured Tc in the ternary alloys, a thermodynamic interaction parameter for the bcc phase of each binary system, constituting the ternary system, has been estimated, and this value has been compared with the existing data.View full abstractDownload PDF (566K) -
Tatsuhiko Ejima, Tsutomu Yamamura, Yoji Arita, Katsuyuki Matsui1975 Volume 39 Issue 4 Pages 409-413
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSDiffusion coefficients of 22Na, 86Rb and 137Cs ions have been determined in molten lithium chloride by using the capillary reservoir method in the temperature range of 650∼820°C.
The results obtained are summarized as follows:
(1) Diffusion coefficients determined were in the order of DNa>DRb>DCs. There is a large difference in the diffusion coefficients of each ions in molten lithium chloride as compared with the cases of sodium and potassium chlorides. Since the hole size of molten lithium chloride is comparable to the size of cations, the diffusion coefficients are largely affected by the size of diffusing particle. This trend becomes less in the cases of sodium and potassium chlorides.
(2) The activation energy for diffusion tends to decrease with increasing enthalpy of mixing at infinite dilution in molten LiCl, NaCl and KCl. This trend may be explained in terms of the interaction energy between solute and solvent ions, particularly by the polarization energy and the London energy.View full abstractDownload PDF (421K) -
Mitsuhiko Yoshida, Saburo Nakamura, Hajime Suto1975 Volume 39 Issue 4 Pages 414-418
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe recrystallization of vacuum-deposited silver and copper films about 2μ in thickness was investigated by means of transmission electron microscopy, electrical resistivity measurements, differential thermal analysis and X-ray diffraction techniques.
The results of observation were as follows:
In the as-deposited silver films, one of the preferential plane orientations parallel to the substrate was {111}. A ratio of diffracted intensity (I200/I111) reached about 0.4 when held at room temperature; the ratio is expected to result from the random orientation. Recrystallization was observed in the temperature range from 30 to 50°C.
For copper, the recrystallization produced an almost complete reorientation such that {100} planes were parallel to the substrate.
From the measurement of heat released during recrystallization, the grain boundary energies for silver and copper were estimated to be 320±60 erg/cm2 and 810±170 erg/cm2, respectively.View full abstractDownload PDF (688K) -
Toshihiro Yamada, Kazuyoshi Hatano, Toshimi Sasaki1975 Volume 39 Issue 4 Pages 419-423
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA study has been made on the rolling wear characteristics of the annealed carbon steels as well as the change of the rolling contact surface under a metal-to-metal dry condition in air using an Amsler-type wear machine. The results obtained are as follows.
(1) The first sharp wear increase took place in the initial period of friction and the subsequent sharp wear increase occurred after exceeding a certain number of revolutions. The number of revolutions which causes the shap wear increase depends on the materials and the load applied and increased with an increase in hardness of the materials and with a decrease in the applying load.
(2) Prior to the sharp wear increase, the occurrence of fine pits or cracks was observed on the rolling contact surface, which disappeared after the sharp wear increase.
(3) It is considered that the fine cracks are initiated in the neighborhood of the rolling contact surface and there is a definite relationship between the Hertzian stress and the number of revolutions where the sharp wear increase took place. These results would suggest a contribution of the fatigue-related factors to the dry rolling wear.View full abstractDownload PDF (491K) -
Masato Sagawa, Masanori Okada, Zenzo Henmi1975 Volume 39 Issue 4 Pages 424-427
Published: 1975
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe relationship between the coercive force and the precipitation sequence in a Co-12Fe-3Nb alloy which was cold-rolled by a 10% reduction in area and then annealed at 700 and 800°C for 1∼100 hr was investigated through measurements of hysteresis loop and electron microscopic observations.
The results obtained are summarized as follows:
(1) The precipitate phase in the fully heat-treated alloy is a hexagonal Laves phase Co3Nb in the form of platelets.
(2) This platelet interface is parallel to the (111) planes of the fcc matrix and the orientation relationship between the matrix and the precipitate of Co3Nb may be described as
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(3) Very fine precipitates can be detected after annealing at 700°C for 1 hr. At longer annealing time the morphology changes into small platelets. At the best heat treatment condition for the high coercive force the platelets are 0.3∼1 μm across and 100∼200 Å thick and a distance between the individual platelets is 2000∼3000 Å. Further growth of the precipitates results in a decrease in coercive force.View full abstractDownload PDF (341K)
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