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Volume 35, Issue 10
Displaying 1-12 of 12 articles from this issue
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Hideo Abe, Kazumasa Togano1971 Volume 35 Issue 10 Pages 947-951
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSContinuous observations have been made on dendritic growth of cyclohexanol crystals from the stagnant or flowing liquid. From the flowing liquid, the secondary spines on the upstream side of primary spines grow very rapidly, while the growth direction of primary spines deflects slightly to the upstream. The columnar crystals with their primary spines tilted to the upstream grow preferentially at the expense of those with their primary spines tilted to the downstream. Dendritic structure of an Al-5%Cu alloy ingot solidified initially from the stagnant melt and subsequently from the flowing one, and the columnar crystal structures in Al-3%Cu and Zn-1.5%Cd alloys solidified from the flowing melts [reported in J.Japan Inst.Met., 33(1969), 970; 34(1970), 993], can be interpreted on the basis of the continuous observations on cyclohexanol.View full abstractDownload PDF (2583K) -
Masuzo Ueda1971 Volume 35 Issue 10 Pages 952-957
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThis investigation was supplementarily carried out to clarify the adhesion mechanism of lead to iron in hot dip lead coating of steel.
The results obtained were as follows.
(1) By comparison with the surface roughness between a cast iron in the as-cast condition and that decarburized at 1000°C for 20 hr in mill scale, after grinding and pretreating to the same degree, the former was rougher than the latter. From this, lead seems to become rich in adhesion to a steel plate because of increasing the surface roughness with increasing carbon content.
(2) In spreading test, lead has poor adhesion to graphite, but steel with decreasing carbon content was increasingly wetted with lead.
(3) PbO is deoxidized by both iron and carbon. By PbO on the surface of a molten lead bath, the steel specimen is oxided and consequently no lead is adhered to it. But, when PbO is deoxidized by carbon in steel, it can easily be coated with lead.
(4) When the steel specimen with a polished surface was coated with lead by electro plating and then heated in H2 gass, the grain boundary impregnation with lead occurred. From this phenomena it is clear that the steel specimen has a finer grain as the more lead adheres to it.
(5) Steel and the (100) or (111) plane on a single crystal of iron were coated with lead by electroplating and then heated in the range 400°C to 850°C for 10 min to 9 hr duration in H2 gass. But no diffusion layer between Pb and Fe was confirmed by X.M.A.View full abstractDownload PDF (3115K) -
Tsuneo Ishida1971 Volume 35 Issue 10 Pages 958-965
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA basic study of iron soldering has been made of the reaction between solid iron and molten tin from the viewpoint of dissolution kinetics and metallography. Small iron cylinders were immersed in molten tin in the temperature range of 445°∼780°C, for 10 to 160 min under the static condition utilizing the soldering flux. The measured value of initial dissolution rate of solid iron into molten tin was 1.43×10−6∼9.05×10−5 g/cm2-sec. A modified rate equation of first-order dissolution reaction was derived. The obtained value of the initial dissolution rate constant was 3.37×10−4∼1.12×10−3 cm/sec and activation energy for the dissolution depends on temperature. The dissolution mechanism in the high temperature range above 496°C differs from that in the low temperature range below 496°C. In the high temperature range,the dissolution process is controlled by diffusion across the effective boundary layer of molten metal immediately adjacent to the alloy layer. In the low temperature range, the process is controlled by formation of an intermetallic compound at the early reaction time, but a transition to reaction control of the alloy layer and molten metal occurs with the elapse of reaction time. The dissolution of solid iron into molten tin proceeds, the alloy layer growing and the layer intensively reacting with molten tin at the same time.View full abstractDownload PDF (2885K) -
Takeshi Nagai, Zenzo Henmi, Iesada Hirai1971 Volume 35 Issue 10 Pages 965-969
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn a previous paper,the retardation of recrystallization in Cu-Cr-, Cu-Zr and Cu-Zr-Cr alloys could not be fully accounted for by either fine precipitates or solute atoms. In this paper, the authors investigated the rolling and annealing textures in these alloys. The rolling textures of Cu-Cr alloy are described by (110)[1\={1}2]+(112)[11\={1}] (Cu type). Cu-Zr and Cu-Zr-Cr alloys have the same textures described by (110)[1\={1}2] (Brass type). But the annealing textures of Cu-Cr alloy are described by (225)[73\={4}]+(100)[001]. Cu-Zr and Cu-Zr-Cr alloys have the same annealing textures described by (110)[112] (Recrystallizatition in situ). If Cr and Zr remain to be solved during recovery and recrystallization, the annealing textures must become the Cu type (100)[001] or the Brass type (225(73\={4}]. The reason for such a difference between the annealing textures of these alloys was considered due to the formation of fine precipitates during recrystallization which obstructs dislocation climbing, sliding and grain boundary migration.View full abstractDownload PDF (1090K) -
Hideo Kaneko, Jun Ikeuchi, Yoji Koide1971 Volume 35 Issue 10 Pages 969-973
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSValve materials require high resistance to lead oxide attack and specific mechanical properties at high temperatures. Iron-base alloys containing up to 30% manganese and 30% chromium have been investigated for the development of a new valve material.
Concerning the corrosion and mechanical properties of Fe-Mn-Cr ternary alloys, the following results have been obtained:
(1) The alloys containing 20% chromium and up to 30% manganese in Fe-Mn-Cr ternary alloys have high resistance to lead oxide attack.
(2) Although the corrosion resistance, in general, is detrimentally affected by the addition of carbon, nitrogen or silicon, such an effect can be prevented in the case of the alloys containing 20% chromium and 20 to 30% manganese. The weight loss caused by lead oxide is about 5 g/dm2/hr and this value is nearly equivalent to that of Nimonic alloys.
(3) From the examination of high temperature strength and hot workability, it is apparent that Fe-Mn-Cr-C-N alloys (containing 25% manganese, 20% chromium, 0.4 to 0.6% carbon and 0.6% nitrogen) have mechnical properties comparable to those of 21-4N steel.
Hence, it may be concluded that these alloys are quite suitable for the exhaust valve material.View full abstractDownload PDF (1501K) -
Minoru Tanaka, Tomoo Suzuki1971 Volume 35 Issue 10 Pages 974-979
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe age-hardening behaviours in Fe-Pt-Mn martensitic alloys which are expected from the previous researches in the age-hardenable Fe-Ni-Mn alloys have been ascertained experimentally in this study.
The results obtained in this study are summarized as follows:
(1) A prominent age-hardening response in the Fe-Pt-Mn martensitic alloys is observed and the strain hardening due to the formation of the coherent zone (probably PtMn β phase) in the matrix will be a major factor of age-hardening as in the case of Fe-Ni-Mn alloys.
(2) Comparing the Fe-Pt-Mn alloys with the Fe-Ni-Mn alloys, the following characteristics are found which are attributable to the prominent hardening response in the former alloys. (i) Because the affinity with the solute atoms Pt and Mn in the Fe-Pt-Mn alloys is stronger than that with Ni and Mn in the Fe-Ni-Mn alloys, the former alloy system has an extended miscibility gap island and a more excessive supersaturation of solute atoms in martensite, thus increasing the precipitated zone. And the bcc PtMn ordered phase and the bcc NiMn ordered phase can be considered as the coherent precipitated zone in both alloy systems respectively. In both precipitated zones, the shearing resistance by the dislocation may depend on the binding affinity in each zone. (ii) Because the lattice strain due to solid solution of Pt and Mn atoms in the Fe matrix is greater than that of Ni and Mn atoms, it can be expected that the strain-hardening response increases in the Fe-Pt-Mn alloys when the precipitation of the coherent zone occurs.
(3) The fct PtMnβ1 phase having a CuAu type ordered structure is observed on the over-aged stages in Fe-Pt-Mn alloys. This β1 phase can also be found in a state of coexisting with ferrite after slow cooling from the austenite region and precipitates from austenite at about 680°C with an exothermic change and an expansion in length.
(4) It may be concluded that in the ternary iron-base martensitic alloys which are composed of a binary alloy system having the bcc phase (containing a CsCl type compound) in 50-50 atomic pct composition and iron, such as Fe-Mn-Pd, Fe-Ni-Zn and Fe-Ni-Pd alloys, an age-hardening response can be expected in a similar way to the Fe-Pt-Mn alloy due to the same hardening mechanism.View full abstractDownload PDF (2426K) -
Kunio Shiobara, Susumu Morioka1971 Volume 35 Issue 10 Pages 980-984
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this paper, the anodic behaviours of Ti on the open surface and Ti in the crevice were investigated in 5 M NaX (X : halogen) and MgCl2 solutions at elevated temperatures (106°∼115°C). Moreover, the effect of temperature was examined. The results obtained are summarized as follows. (1) In the potential region investigated, pitting and crevice corrosion occur above 85°C and the critical potential for the former is considerably higher than that for the latter. This indicates the less susceptibility to pitting of the open surface. The pitting potentials of Ti in the halide solutions are in the following order : Ep(Cl)115°C=+3 V>Ep(Br)108°C=+0.8 V>Ep(I)110°C=+0.3 V. On the contrary, the crevice corrosion potentials are in the order : Ecre(Cl)115°C=−0.4 V<Ecre(Br)108°C=+0.2 V<Ecre(I)110°C=+0.3 V. (2) It is considered that titanium in the crevice is polarized anodically to react with halide ions because of the limited supply of H2O molecules in the narrow crevice and forms a soluble substance which causes crevice corrosion. (3) The gas evolved on the titanium anode in sodium sulphate solution is identified to be oxygen. This fact indicates that the anodic oxide film formed on titanium displays semi-conductivity which increases electronic conductivity as the potential and the temperature are increased.View full abstractDownload PDF (2140K) -
Hakaru Masumoto, Yûetsu Murakami, Masakatsu Hinai1971 Volume 35 Issue 10 Pages 985-988
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSMeasurements of magnetic properties, electrical resistivity and hardness have been carried out for Ni-Fe-Nb alloys of 72.98∼84.67%Ni, 6.59∼24.36%Fe and 2.43∼13.90%Nb heated in pure hydrogen atmosphere at 1100°C for 3 hr and then cooled at various rates. It is shown that the addition of Nb exceedingly improves the magnetic properties of Ni-Fe alloys. The highest values of 42300 in initial permeability and 179000 in maximum permeability are shown by the compositions of 79.56%Ni, 12.04%Fe and 8.40%Nb and of 79.62%Ni, 11.05%Fe and 9.33%Nb when cooled from a temperature above the order-disorder transformation point at a rate of 240°C/hr, respectively. The coercive forces of these two alloys for a maximum magnetic induction of 5000 G are 0.0107 and 0.0112 Oe, respectively, and the magnetic inductions in an effective magnetic field of 1000 Oe are 6550 and 5690 G, respectively. The electrical resistivity and Vickers hardness of the latter alloy are 69.5 μΩ-cm and 215, respectively.View full abstractDownload PDF (1279K) -
Eiichi Takeuchi, Masuo Tanaka1971 Volume 35 Issue 10 Pages 989-997
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThis study was conducted to scrutinize the behavior of lubricants in the deep drawing of a stainless steel sheet.
The cofficient of boundary friction and the oil film strength were investigated on three kinds of polybutene of different viscosity and the same lubricants to which stearic acid as an oiliness improver and dibenzylpolysulfide or chlorinated paraffin as an extra-pressure agent were added. Then the effect of the lubricants on the workability of materials was studied chiefly by means of checking the “metal transfer” phenomena of the materials which appeared on die blocks when deep drawn under a blank holding force of 200 kg and a punch speed of 18 cm/min.
In case of the deep drawing of a SUS-27 stainless steel sheet, which belongs to one of materials which can hardly be processed, the use of a lubricant having an extremely high viscosity presented a wide hydrodynamic lubrication range on the contact surface between the material and die block, and this range seems to suppress the “metal transfer” phenomenon of material. However, the lubricants of low or medium viscosity to which oiliness improver or extra-pressure agent is added, does not show any remarkable tendency to improve the maximum drawing force or the roughness of the outer surface of the cup wall of the material, in spite of the improvement in their coefficients of boundary friction or oil film strengths. In case of the treatment of materials under a condition where the lubricative efficiencies of the additives exert a favourable influence, “metal transfer” phenomena of materials can scarcely be detected, resulting in greatly improving the drawability of materials. In the present study it has been confirmed that only the addition of chlorinated paraffin which brings out a chemical reaction with steel at a comparatively light load can meet such a condition.View full abstractDownload PDF (3063K) -
Hiroshi Tanaka, Yasuo Kishida, Akio Yamaguchi, Joichiro Moriyama1971 Volume 35 Issue 10 Pages 997-1000
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe standard free energy of formation of Mn7C3 in the temperature range 620° to 800°C was determined by means of E.M.F. measurements using a single crystal of calcium fluoride as a solid electrolyte. The construction of fluorine concentration cell was
(This article is not displayable. Please see full text pdf.)
From the E.M.F. values of above cell, the standard free energy of formation of Mn7C3 was calculated as follows:
(This article is not displayable. Please see full text pdf.)View full abstractDownload PDF (725K) -
Osamu Kawano, Tetsuya Hirouchi, Hiroyuki Yoshida, Yotaro Murakami1971 Volume 35 Issue 10 Pages 1001-1007
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe size of a platelike G.P.(1) zone in Al-Cu alloys has been investigated by the X-ray small-angle scattering photographic method. As its applications, the growth behaviour of G.P.zones in different ageing temperatures, the relation between its size and the peak of electrical resistivity ageing curves and the effects of Sn addition on the G.P.(1) zone formation and growth have also been investigated.
In order to measure precisely the scattered intensity around the direct beam, it is essential to minimize the shadow part by the beam stopper. In this research the upper limit of the determined diameter was about 60 Å.
On the growth behaviour of G.P.(1) zones in the binary Al-Cu alloy, a clear difference between 100° and 135°C was found. For the contribution of G.P.zones to the peak on the resistivity ageing curve it was shown that the critical diameter for the peak appears to be larger than 50 Å, in contrast with the case of the spherical zones in Al-Ag or Al-Zn alloys. The effects of 0.12 wt%Sn addition on the growth of G.P.(1) zones was found to be dependent on the ageing temperatures.View full abstractDownload PDF (1828K) -
Norio Sato, Kiyokatsu Kudo, Masayoshi Miki1971 Volume 35 Issue 10 Pages 1007-1016
Published: 1971
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe anodic passivity of nickel in neutral solutions has been investigated by means of potentiostatic oxidation, galvanostatic reduction and chemical analysis techniques, and the thickness of anodic oxide film and the effect of solution pH and of anion species on the passivation behaviour are examined. It is shown that the oxide film formed by anodic oxidation is difficult to be removed by cathodic reduction in neutral solution. To obtain a bare surface, cathodic reduction has to be carried out in sulphuric acid for oxidized surfaces and either in acid or in neutral solution for electropolished surfaces.
In the passivity region, where NiO film is assumed to be formed, nickel dissolution is still observed during oxidation and the amount of nickel dissolved is dependent on the oxidation potential, the solution pH, and the anion species present. The film thickness estimated from coulometry in the pH range 5.5 to 9.5, however, is not practically affected by the solution pH and the anion species but increases linearly with rise of the potential from 6 to 16 Å.
Above the potential of passivity region, the secondary passivation occurs where nickel dissolution is not detected. It is also shown that the secondary passivation is due to the formation of a higher valence nickel oxide, probably Ni2O3, which may be electrodeposited from dissolved Ni2+ ion in solution. The thickness, estimated from the potential decay curve of galvanostatic reduction, increases rapidly with rise of the potential and then decreases through a maximum. Further rise of potential results again in the dissolution of nickel independent of the solution pH and the anion species.
The growth kinetics of both the passivation film and the secondary passivation film is concluded to obey the inverse logarithmic rate law.View full abstractDownload PDF (2630K)
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