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Volume 18, Issue 11
Displaying 1-13 of 13 articles from this issue
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Taketo Yokoyama1954 Volume 18 Issue 11 Pages 557-561
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSBrinell hardnesses of soft metals i.e. tin, lead, their eutectics, babbitt metals, cadmium, zinc, and also aluminium, copper, brass, mild steel were measured by changing the amount of the load applied, the length of the time of maintaining the load, and also the temperatures of the specimens. A new relationship between the load p kg, the length of time t sec., and the diameter of the impression dmm, was determined as follows: P=(A-B logt) {1+2.3026 (n_0-2 ±m logt) logd}d^2
where A, B, n0, and m are constants which are also functions of the temperatures of specimens. Researches on the phenomena of the flow of metal, (also creep, relaxation) work-hardening, spontaneous annealing and recrystallization were carried out and discussed.
A new discriminative equation for the spontaneous annealing or work-hardening was deduced.
Also, new constants in which “n0” shows the workability and “s0” shows the flow index which depends on the degree of the work-hardening and the flow of metals were determined. In the Brinell test, the effects of quenching, loading speeds, repeated loadings and the size of the ball used were examined.View full abstractDownload PDF (706K) -
Jingozaemon Matsuoka1954 Volume 18 Issue 11 Pages 561-565
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt has been reported that mechanical properties are improved by applying “Strain Tempering (KRK)” process to steel wires containing 0.6∼0.9% C. In this paper the effect of carbon content of steel wires on the mechanical properties in this process has been investigated. Results obtained are as follows: (1) In the case of low carbon steel wires, tensile strength, yield strength and hardness are also improved by this process. These improvements in strength and ductility are expected by adopting suitable conditions of this process as in the case of high carbon steel wires (2) The strength increases with carbon content and reduction are increased, but the maximum strengthening is determined by the relation of carbon content, reduction and treating temperature.View full abstractDownload PDF (981K) -
Saburô Shimodaira1954 Volume 18 Issue 11 Pages 566-569
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the case of cathodic control (activation control), the corrosion rate is given by
(This article is not displayable. Please see full text pdf.)
Where K1 is the specific rate constant of cathodic reaction, C is the concentration of the adsorbed water molecules in the Eyring’s prototropic process, 1>α>0 and E is the natural eletrode potential. In the case of “mixed control” (where the cathode reaction is controled by activation process and the anode reaction is controled by diffusion process), the corrosion rate has no dirrect connection with the natural electrode potential and is a function of pH and the standard electrode potential of metal.
(This article is not displayable. Please see full text pdf.)
where n is the valency of the metal ions and EM0 is the standard electrode potential of metal. The heat of activation in the cathode reaction is one of the most important factors of the corrosion reaction and is calculated by the following equation. ΔH=1380 (2.1-logi-8.4V) (25°) where i is the cathode current density and V is the overvoltage.View full abstractDownload PDF (700K) -
Saburô Shimodaira1954 Volume 18 Issue 11 Pages 570-573
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the case of “mixed control”, the natural electrode potential is given by E=\frac2.303RT(n+α)F log\fracK_1Cn - \frac2.303αRT(n+α)F pH + \fracnn+α E_M^0 + \frac6.909RT(n+α)F + \frac2.303RT(n+α)F log\fracδDwhere K1 is the specific rate constant of cathode reaction, C is the concentration of the adsorbed water molecules on the metal, 1>α>0, n is the valency of metal ions, EM0 is the standard electrode potential of metal, δ is the thickness of the diffusion layer and D is the coefficient of the diffusion. The equation fairly holds on some metals. The equation gives the following cnoclusions; the hydrogen evolution type corrosion cannot occur with mercury, hismuth, copper, and silver. Hydrogen does not evolve in the range of pH higher than 5 to 6 with nickel, lead and tin. The corrosion should cease at pH 9 with iron in air-free solutions. Chromium and cadmium resemble iron. Aluminum would be thoroughly corroded evolving hydrogen gas in all concentrations of alkaline solutions.View full abstractDownload PDF (653K) -
Renpei Yoda1954 Volume 18 Issue 11 Pages 573-578
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to establish the foundation of the industrial production of magnesium nitride (Mg3N2), the condition of its preparation was determined by observation of the reaction between magnesium and nitrogen; the size of magnesium, the outflow velocity of nitrogen, the heating temperature and the heating times were experimentally discussed. The results are as follows: (1) Magnesium nitride can be prepared most efficiently by introducing 100 cc of N2 per min on filings or lathe-scraps of amagnesium containa iron boat at 900° for 1 hour. (2) The more the inflow velocity of nitrogen increases, the shorter the time of the reaction between magnesium and nitrogen becomes, and the larger the size of magnesium becomes, the higher the temperature of the reaction rises. (3) The purity of the nitride formed from coarse lathe-scraps of magnesium was higher than in the case of the fine filings. (4) Small amounts of MgO and Mg (OH)2 were contained in the nitride. The nitrided products must be preserved in a closed dry vessel. (5) Magnesium nitride heated in dry air was oxidized at 460∼600°. (6) Magnesium nitride heated in vacuum was found to decompose from about 900°, and its dissociation pressure was almost 1 atm. at about 1170°. (7) Nitride products must be of high purity, prepared at above 800° and of the size of about 50 mesh to be effective in inducing prompt spheroidization of graphite.View full abstractDownload PDF (1081K) -
Etsujiro Yajima, Teijiro Shibata1954 Volume 18 Issue 11 Pages 578-581
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSVarious kinds of Al diffused electrical heat-resisting wires were measured for their specific electrical resistance and mechanical strength. The specific electrical resistance of nichrom wire did not increase by Al diffusion, but by Fe-Cr-Al wire it increased. The mechanical strength of these Al diffused wires was almost the same as before the diffusion.View full abstractDownload PDF (581K) -
Tadamichi Takei1954 Volume 18 Issue 11 Pages 582-583
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAn intermittent arc source unit was constructed for the determination of small amounts of silicon and tin in iron and steel. The triggering spark current of the unit was wholly electronically controlled with thyratrons and it was possible to change continuously the frequency of interruption and the ratio of arc duration to the time the current is interrupted. This source unit, combined with either a large Littrow-type or a medium quartz spectrograph, proved to give satisfactory results in determining 0.008 to 0.163% Si and 0.010 to 0.145% Sn.View full abstractDownload PDF (371K) -
Mikio Yamamoto, Satoshi Taniguchi1954 Volume 18 Issue 11 Pages 584-588
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSΔE-effects and Young’s moduli in annealed and in quenched states of ferromagnetic iron-aluminium alloys containing less then 17 percent aluminium have been measured with the method of magnetostrictive vibration. In the whole composition range a small negative ΔE-effect has been observed at low fields both in annealed and in quenchedstates, and a secondary increase of the ΔE-effect has been found in alloys containing less than 4 percent aluminium. The saturation value of the ΔE-effect in annealed state shows three maxima at about 8, 12, and 14 percent aluminium, of which the second and the third maxima disappear completely by quenching, indicating that the ΔE-effect increase to a greater extent with the superlattice formation of Fe3Al. Young’s modulus both in unmagnetized and in magnetically saturated states, shows a deep minimum at about 13 percent aluminium, and the relative increase in Young’s modulus in magnetically saturated state due to quenching is found to be only about 2 or 3 percent, indicating that the low value of Young’s modulus at about 13 percent aluminium has no direct correlation with the superlattice Fe3Al.View full abstractDownload PDF (811K) -
Hiroshi Watanabe1954 Volume 18 Issue 11 Pages 588-591
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSX ray powder photographs have been taken of samples of the system SrO-Fe2O3 and it is found that at least three phases are present in this system; one of them is of the hexagonal magnetoplumbite structure, which is strongly magnetic. Another one, corresponding to the composition of 0.7 SrO 0.3Fe2O3 is cubic, with its lattice constant equal to 3.86×n Å, where n is an integer. This is not ferromagnetic at room temperature. The last phase, whose crystallographic symmetry is unknown, occurs at the composition SrOFe2O3. The observed ferromagnetism seems to originate exclusively from the magnetoplumbite structure.View full abstractDownload PDF (612K) -
Sadakichi Kitajima1954 Volume 18 Issue 11 Pages 592-594
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThermal etch-pits grubbed up on the surfaces of high purity aluminium with coarse grains by annealing at 580°, in vacuum of 10−4∼10−5 mm Hg were microscopically observed. According to the observational results, the density of the thermal etch-pits was not definite but varied with grains. The density of thermal etch-pits on the {100} surfaces is always smaller than that on the {111} and {110} surfaces.View full abstractDownload PDF (559K) -
Mikio Yamamoto, Jirô Watanabé1954 Volume 18 Issue 11 Pages 595-598
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe light-figure phenomenon has been observed with single crystals of nickel-copper alloys containing 20∼80 percent copper, etched with various reagents, and information regarding the crystal planes developed by etching and the suitability of light figures to the orientation determination have been obtained. Etching with boiling saturated aqueous solution of ferric chloride produces distinct light figures, suitable for the orientation determination, for all of alloy crystals, while any other reagent reveals only indistinct or no light figure. The crystal planes developed by etching with ferric chloride solution are, beside the {lm0} (l⁄m<1.5) and nearly {111} planes commonly developed in all alloy crystals, the {610} and {811} planes in 20%Cu crystals, locally the {610} and {811} planes and locally the {510} planes in 30%Cu crystals, the {510} planes in 40∼70%Cu crystals, and the {310} planes in 80%Cu crystals, indicating that crystal planes of lower indices may be developed in alloy crystals of higher copper content.View full abstractDownload PDF (647K) -
Koichi Furusawa, Akio Kojima1954 Volume 18 Issue 11 Pages 599-602
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWe studied, under various conditions, about the morphology of ferrite during the formation of banded structure. The results obtained were as follows. (1) During continuous cooling (2°/min) from quenching temperature, ferrite nuclei begin to arrange along the rolled direction at the degree just under Ar3. (2) Isothermal transformation was done and ferrite nucleation and growth are shown by the microphotographs. (3) Ferrite nucleation was not influenced by the existence of MnS but its growth seemed to be. (4) By studies of Ni-Cr steels, we presumed that the cause of banded structure was the banded segregation of non-diffusible elements e.g. Ni, Cr and Mn.View full abstractDownload PDF (1218K) -
Takuya Imai, Shigetaro Togashi1954 Volume 18 Issue 11 Pages 603-606
Published: 1954
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAnalytical methods of ferroalloys have been applied to those of iron and steel. But there are many unsuitable points because of the difference of other alloys from iron and steel, for ferroalloys contain much Mn, Si, Cr, W, Mo, V, Ti, P, Ca (Ni, Zr, B, Co, Ta and Al) etc. as the ordinary constituents beside iron. Now, ferroallys app-proved in Japanese Industrial Standards (J.I.S.) are inspected in a different section from that for iron and steel. Often there is a differerence between a conent and its analytical value in ferroalloy, caused by its segregation or errors of analytical method. We calculated and compared the standard deviation (σ) for each analytical method. Hereunder we report those results with reference to the allowance that has been tolerated in practise.View full abstractDownload PDF (713K)
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