Journal of the Japan Institute of Metals and Materials
Online ISSN : 1880-6880
Print ISSN : 0021-4876
ISSN-L : 0021-4876
Volume 36 , Issue 9
Showing 1-18 articles out of 18 articles from the selected issue
  • Hakaru Masumoto, Kiyoshi Watanabe
    1972 Volume 36 Issue 9 Pages 827-833
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Crystal structures and magnetic properties of Pt-Mn-Sn alloys have been investigated by means of X-ray and magnetic analysis. It has been found that C1 or C1b type compound PtMnSn exists in the Pt-Mn-Sn system and forms solid solutions in the compositional range of Pt1.05Mn0.90Sn1.05∼Pt0.94Mn1.12Sn0.94. These alloys in solid solution have lattice parameters of about 6.271∼6.249 Å at room temperatures, saturation magnetizations of 45.0∼55.0 emu/g at absolute zero, magnetic moment of 3.25∼3.37 μB per Mn atom at absolute zero, and the Curie temperatures of 313∼365°K.
    The magnetic susceptibility of these alloys has been found to satisfy the Curie-Weiss law above the Curie temperature.
    Download PDF (1913K)
  • Shigeo Muromachi, Shigeo Zaima, Yuzo Takatsuji
    1972 Volume 36 Issue 9 Pages 833-840
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Six sorts of aluminium-silicon JIS commercial cast alloys, i.e. AC2BF, AC2BT6, AC3AF, AC4AF, AC4AT6 and AC4BF, were examined on drill-machinabilities in regard of drilling resistance, accuracy of drilled holes, deposits on the drill face, chip treatment and others. The results obtained were summarized as follows:
    (1) In the case of F-materials (as-cast), the drilling resistance and time were smaller in copper-containing materials, i.e. 2BF and 4BF, and were larger in 4AF, especially 3AF. And the drilling resistance and time of T6-materials (heat-treated) were larger than those of F-materials.
    (2) The drilling temperature was lower in 4AT6 than in the other materials, but the temperatures were about 100∼120°C as a whole and posed no serious problem.
    (3) In the case of F-materials, the accuracies of drilled holes, i.e. enlargement of the hole diameter, roundness of the hole figure and surface roughness of the drilled hole in 4AF and 3AF were inferior to those in 2BF and 4BF, and the roundness of the hole figure and the surface roughness of holes in T6-materials were better than those in F-materials.
    (4) In the case of F-materials, the deposits, such as a cohesive large built-up edge, which deteriorate the accuracy of a drilled hole, were observed on the drill face. This phenomenon was more remarkable in 4AF, especially 3AF than in 2BF and 4BF. And the deposits in T6-materials were less cohesive and smaller than those in F-materials.
    (5) There were no difficulties in chip formation regardless of the chip treatment.
    Download PDF (2915K)
  • Yasuhiko Miyoshi, Satoshi Kado, Tadao Azami
    1972 Volume 36 Issue 9 Pages 841-846
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The oxidation behaviours of pure Fe, Fe-Si alloys with 0.08∼1.92%Si and Fe and 0.31%Si-Fe alloys containing about 0.05%Sn and Sb were studied at 700°C in air by means of a thermo-balance, X-ray diffraction, spectroscopy, optical microscopy and EPMA. At the same time Pt marker measurements were carried out. The results obtained are summarized as follows:
    (1) Sn and Sb considerably decrease the oxidation rate of 0.31%Si-Fe alloy, while they have no effect on that of pure Fe.
    (2) The oxide scales formed on dilute Fe-Si alloys consist of layers of hematite, magnetite, wustite and wustite+fayalite. The composition is not influenced by small additions of Sn and Sb.
    (3) Pt markers were found on the wustite/wustite+fayalite interface. From this observation it is concluded that oxidizing gases are transported inward in the gas phase across the innermost oxide layer, i.e. wustite+fayalite and oxidize the alloy. The growth of the oxide film on dilute Fe-Si alloys proceeds, therfore, through both the outward diffusion of Fe ions and the inward diffusion of oxidizing gases.
    (4) Owing to the slower diffusion rate of Fe ions through fayalite than through iron oxides, Si additions improve the oxidation resistance of Fe. EPMA measurements confirmed that the concentration of fayalite in the innermost oxide layer increases with increasing Si content.
    (5) On the other hand, Sn and Sb additions to 0.31%Si-Fe alloy do not bring about a higher concentration of fayalite, but cause the change of the nature of the innermost oxide layer. Since the diffusion rate of oxidizing gases through this layer probably depends on its nature, e.g. porosity, the protective effects of Sn and Sb can be explained to be due to the change of its nature.
    Download PDF (2488K)
  • Hidemi Kimata, Seiki Nishi
    1972 Volume 36 Issue 9 Pages 846-852
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Silver alloys containing 0.10, 0.20, 0.45 and 0.56 wt%Be were heated at 820°C in ∼10−3 mmHg or in still air for 2∼16 hr. The contact resistance was measured at the surface as-heat treate and 0.20 mm scraped from the surface.
    The results obtained were summarized as follows:
    (1) Resistivity of internally oxidized samples was higher than the non-oxidized one. On oxidizing, the resistivity of Ag-0.20 wt%Be changed from 1.9×10−6 to 2.2×10−6Ω-cm and that of Ag-0.45 wt%Be from 2.0×10−6 to 3.0×10−6Ω-cm.
    (2) In Ag-0.10∼0.45 wt%Be alloys the contact resistance on the surface as-heat treated in a ∼10−3 mmHg atmosphere were higher than those of the heat treated specimens in still air. In Ag-0.10∼0.45 wt%Be alloys the contact resistance on the surface as-heat treated in still air was almost equal to that of pure silver.
    (3) Contact resistance at the position 0.2 mm below the surface was nearly equal to that of pure silver in the case of both heat treatments, except for Ag-0.45 wt%Be alloy. Contact resistance of Ag-0.45 wt%Be internally oxidized was higher than that of the non-oxidized.
    (4) The relation between contact resistance and load was generally expressed by R=K·Pm. The value of m for the position 0.2 mm below the surface was determined as about −\frac13 at the loads from 50 to 1000 g.
    Download PDF (2461K)
  • Atsushi Takei, Kazuyoshi Nii
    1972 Volume 36 Issue 9 Pages 853-859
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The growth process of oxide layers in the initial oxidation of 80Ni-20Cr alloy has been studied in the temperature range from 500° to 1000°C in air by means of electron diffraction and X-ray microanalysis.
    The oxide film formed in a quite early stage (e.g. at 600°C for 1 min) was found to have a NiO structure, while the amount of Cr in the film was twice as much as that of Ni. By annealing of the stripped oxide film the electron diffraction pattern was changed to sharp strong patterns of Cr2O3 containing NiCr2O4 and NiO.
    The X-ray microanalysis of oxide films formed at 600°C for 1∼1080 min showed that the Cr content in the oxide layer increased with oxidation time, whereas the Ni content remained constant.
    From the present results the following growth process can be constructed. At the beginning of oxidation, this alloy is oxidized at the alloy composition of 80Ni-20Cr. The oxide crystal structure is of NiO. Cr content in the oxide film increases by preferential oxidation of Cr at the inner oxide layer during the oxidation, and thus the concentration gradient of Cr is built up in the oxide layer, from the composition of NiO at the outerlayer to nearly the composition of Cr2O3 at the inner layer. Due to the epitaxial relationship with the outer NiO structure, the oxide continues to be of NiO structure despite an increase in Cr content at the inner layer. As the oxidation continues, a continuous layer of stable corundum type Cr2O3 is formed at the inner layer. Then, the Cr2O3 layer acts as protective for oxidation and oxidation rate is controlled by diffusion of Cr through the Cr2O3 layer.
    Download PDF (2626K)
  • Yuzo Oda, Yoshiyuki Mizutani, Koichi Nakajima
    1972 Volume 36 Issue 9 Pages 859-864
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Changes in the composition and structure of Al-Sn and Cu-Sn-Pb bearing materials during operation were examined by means of X-ray diffraction, electron probe microanalysis and electron microscopy.
    It was found that evolution of heat and severe plastic flow of the surface layer caused squeezing of Sn in Al-Sn alloys and diffusion of Sn into Cu in Cu-Sn-Pb alloy, resulting in the formation of intermetalic compounds such as ε-Cu3Sn. Similar change was obtained by heating an unused Cu-Sn-Pb bearing at 170°C for 120 hr.
    It is suggested that the behavior of Sn is a contributory factor in bearing lubrication or failure.
    Download PDF (2063K)
  • Michio Nagasaka, Yoshitaka Shikano, Toshiro Yamashina
    1972 Volume 36 Issue 9 Pages 865-868
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The oxidation kinetics of Ti-15Mo-5Zr alloy at low oxygen pressure of 4×10−5 to 2×10−4 Torr has been studied in the temperature range of 500 to 900°C by means of a microbalance. The results are summarized as follows. (1) The oxidation proceeded obeying to linear rate law for about six hours under the experimental condition of 600 to 900°C and 4×10−5 to 2×10−4 Torr. Tte oxidation rate of the alloy was observed to be lower than that of pure titanium at 700°C for each pressure. (2) The linear rate constant was proportional to oxygen pressure at each temperature, and therefore, the ratio of linear rate constant to oxygen pressure was found to be constant at each temperature, i.e., 7.9×10−5 for 600°C, 7.0×10−5 for 700°C, 6.4×10−5 for 800°C and 6.3×10−5 (g·cm−2·sec−1·Torr−1) for 900°C, respectively. As is obvious from these values, abnormality has been recognized in the temperature dependencey on oxidation rate, that is, the rate decreased as the oxidation temperature increased. (3) The dependency of oxygen pressure on the oxidation rate was discussed on the assumption that the adsorption process of oxygen onto the metal surface might be the rate determining.
    Download PDF (1015K)
  • Taira Okamoto, Katsuhiko Kishitake
    1972 Volume 36 Issue 9 Pages 869-874
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The effect of solidification variables, and the kind and amount of solute elements on the dendrite spacing of columnar crystals in tin binary and ternary alloys with antimony and lead as solute elements has been investigated. Columnar dendrites on a transverse section form Y-like or elliptic cells and they line up in rows. Dendrite spacing, that is spacing between rows, LI and cell spacing, LII are proportional to the square root of the reciprocal of cooling rate, Vs. Then the spacings can be described as follows:
    (This article is not displayable. Please see full text pdf.)
    In the proportional expression, proportional constant, A depends on the kind and amount of solute elements. In aluminum alloys, it was found that value of A was proportional to the square root of amount of solute and the proportionality was not satisfied at high solute content. In tin binary alloys, the value of A in each expression for LI and LII increases with increasing solute content, and is not in proportion to the square root of solute content similarly to the case of aluminum alloys with high solute content. In tin ternary alloys, the value of A for LI increases with increasing amount of solute and the solute elements have an additive effect on the value of A. The value of A for LII increases with differing from the ratio of Sb%/Pb%=1/2 at a given total solute content.
    Download PDF (2873K)
  • Hiroshi Yamamoto, Gen-ichi Kamoshita
    1972 Volume 36 Issue 9 Pages 875-880
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The conditions of powder metallurgy and drawing processes which are required to develop the ductility of the filament were previously reported by the present writers.
    About the developed filaments as mentioned above, the present experiment was done to find the best heat-treatment conditions, including temperature, duration time and heating rate, for a remarkable increase in filament ductility.
    The filaments which were secondarily recrystallized by heating at temperatures lower than 2200°C and for a duration longer than 15 min or at a heating rate lower than 36.3°C/sec gained remarkabl ductility, that is, the elongation of the coiled coil filaments exhibited 600 to 800% which were several times greater than the elongation value of usual filaments.
    The contaminating effect of Ni or Fe coexisting with the filament under recrystallization on the filament ductility was examined too. It was shown that Ni generally reduced the recrystallization temperature and ductility of the filaments. However, if Ni or Fe reacted with the secondarily recrystallized filment, these elements increased filament ductility.
    Download PDF (2744K)
  • Hakaru Masumoto, Shôhachi Sawaya, Michio Kikuchi
    1972 Volume 36 Issue 9 Pages 881-885
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Measurements of Young’s modulus at −150∼400°C and rigidity modulus, thermal expansion and hardness at room temperature have been carried out with Mn-Ni-Cr alloys subjected to a variety of heat treatment and cold working. It was found that in Young’s modulus vs temperature curves, the ternary alloys slow coold after heating for 1 hr at 950°C showed distinct anomalous changes related to their antiferromagnetic\ ightleftarrowsparamagnetic transformations. Young’s modulus at room temperature is higher in the state of annealing than in the cold working or water quenching state and the reheating state after cold working or water quenching, and the values tend to increase with increasing nickel and chromium contents. The temperature coefficient of Young’s modulus shows a wide variation with annealing, water quenching, cold working, and reheating after water quenching or cold working, and also with alloy composition. The temperature coefficients of Young’s modulus as a function of composition exhibit a large positive maximum, thus showing the Elinvar property. The variation in rigidity modulus and its temperature coefficient with the process of heat treatment, cold reduction rate and composition shows a close similarity to that in Young’s modulus and its temperature coefficient. The hardness shows a very complicated change with the process of heat treatment, cold reduction rate and alloy composition, showing the Vickers hardness of about 100 to 550. Further, the corrosion resistance of Mn-Ni-Cr alloys is fairly large.
    Download PDF (1793K)
  • Hakaru Masumoto, Shôhachi Sawaya, Michio Kikuchi
    1972 Volume 36 Issue 9 Pages 886-890
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Measurements of Young’s modulus at −150∼400°C and rigidity modulus, thermal expansion and hardness at room temperature have been carried out with Mn-Ni-Fe alloys subjected to a various procedures of heat treatment and cold working. In Young’s modulus vs temperature curves, the ternary alloys slowly cooled after heating for 1 hr at 950°C showed distinct anomalous changes related to the antiferromagnetic\ ightleftarrowsparamagnetic transformation. Young’s modulus at room temperature showed no remarkable difference by the annealed, cold worked or water quenched states, but the value tended to increase with increasing manganese or iron contents. The temperature coefficient of Young’s modulus showed a wide variation with annealing, water quenching, cold working, and reheating after water quenching or cold working, and also with alloy composition. The temperature coefficient of Young’s modulus as a function of composition exhibited a large positive maximum, thus showing the Elinvar property. The variations in rigidity modulus and its temperature coefficient showed a close similarity to those in Young’s modulus and its temperature coefficient. The hardness showed a very complicated change with the process of heat treatment, cold reduction rate and alloy composition, showing the Vickers hardness of about 100 to 900. Further, the corrosion resistance of Mn-Ni-Fe alloys is fairly large.
    Download PDF (1689K)
  • Masahiro Kitada, Toshio Doi
    1972 Volume 36 Issue 9 Pages 891-896
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Applied magnetic field (H) vs critical current density (Jc) characteristics of Nb-(55∼75)Ti-5Zr and Nb-(55∼65) Ti-1Ge sheets aged at 350 to 500°C were measured at 4.2°K to examine the anisotropic effect. The results are as follows:
    (1) Nb-(55∼75)Ti-5Zr sheets show the largest critical current density at a composition of 65 at%Ti. For the sheet aged at 350°C for 25 hr, Jc(\varparallel) and Jc(⊥), critical current densities where the magnetic field is applied parallel and perpendicular to the sheet plane, are 6.3×104 and 3.4×104 A/cm2, respectively, at 80 kOe.
    (2) The ratio of Jc(\varparallel)⁄Jc(⊥) of Nb-Ti-Zr sheet decreases with increasing Ti concentration, and the minimum Jc(\varparallel)⁄Jc(⊥) ratios obtained for Nb-55Ti-5Zr and Nb-75Ti-5Zr sheets are 4.5 and 1.3, respectively.
    (3) The ageing time making the critical current density maximum for Nb-Ti-Ge sheets is shorter than that of Nb-Ti-Zr sheets. Moreover, the critical current density of Nb-Ti-Ge sheets at high magnetic fields is considerably larger than that of Nb-Ti-Zr sheets. For the Nb-60Ti-1Ge sheet aged at 500°C for 10 hr, Jc(\varparallel) and Jc(⊥) are 1.1×105 and 6.1×104 A/cm2, respectively, at 80 kOe.
    Download PDF (2103K)
  • Hajime Suto, Shuichi Miyake, Katsumi Miura
    1972 Volume 36 Issue 9 Pages 897-902
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The effect of thermomechanical treatment on the impact value at low temperature, hardness and tensile strength of modified 9% nickel steels containing various amounts of manganese, copper, molybdenum and niobium was investigated. By replacing nickel with manganese, the impact value decreased remarkably. Molybdenum was effective in enhancing the toughness by supressing temper-brittleness. Copper and niobium were effective for the strengthening, but their effects on the impact value were relatively small. Thermomechanical treatment showed remarkable effects upon increasing the strength and low temperature toughness. The major reasons were considered to be the refinement of structure and supressing temper-brittleness.
    Download PDF (2609K)
  • Kiyotsugu Ohji, Keiji Ogura, Tomoki Hasegawa
    1972 Volume 36 Issue 9 Pages 903-907
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    In order to investigate the effect of hydrostatic pressure on the low-cycle fatigue strength, a push-pull fatigue testing machine under high pressure was developed. Using this machine, strain-controlled low-cycle fatigue tests were carried out on 5005 aluminum alloy specimens under several different pressures.
    The fatigue test results under high pressures were found to be expressed by linear relations on the log-log scale between the strain range and number of cycles to failure. Increasing the pressure from 0 to 3900 kg/cm2 slightly increased the fatigue life of this material, although this increase of fatigue life was considerably less than that expected from the Manson-Coffin relation through the pressure dependence of fracture ductility. Suppression of the tensile stress component of the applied stress by pressure did not yield any discrete change in fatigue life. This may be interpreted that under high strain amplitude conditions the strain range is a primary factor determining fatigue failure including fatigue crack propagation. Some micrographic studies revealed little effect of pressure on the surface slip process under cyclic strain and also on the appearance of the final fracture surface. Coating of the specimen had little effect on the fatigue life.
    Download PDF (2224K)
  • Michio Ohta, Yasuhiro Miura, Akira Kiyonaga
    1972 Volume 36 Issue 9 Pages 908-912
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Dislocation motion in copper was studied by dislocation-etching before and under loading, and also after unloading.
    Copper single crystals (nominally 99.999%Cu) were first grown in vacuum by the Bridgman technique and parallelepipeds were cut out and polished by an acid saw and an acid polisher. The parallelepipeds were then subjected to thermal cyclic annealing. Final dimensions and dislocation density of the specimen crystals were approximately 5×4×50 mm3 and 1×103/cm2, respectively. Small tensile stress was applied by hanging a small weight.
    Principal results were as follows;
    (1) Dislocation locking force due to impurity atoms and lattice frictional force were estimated to be less than 0.46 g/mm2 and 0.20 g/mm2, respectively.
    (2) Both grown-in and multiplied dislocations were observed to move backward after unloading; multiplied dislocations more frequently.
    (3) Main obstacles to moving dislocations are probably forest dislocations.
    Download PDF (2127K)
  • Michiko Hamasaki, Isao Gokyu, Shunichi Okamura
    1972 Volume 36 Issue 9 Pages 913-920
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    This investigation was carried out on the r-value of the 18% chromium stainless steel, to obtain a fundamental knowledge of the secondary-workability.
    The results obtained are as follows:
    (1) The r-values of the fracture points of AISI type 430 stainless steel annealed specimens are constant and are not affected by strain rate.
    (2) The r-values of the {001}⟨110⟩ regions in the specimens compressed to the III stage region (\dotε=0.0325/sec, ε=0.4, n=0.34) become the increasing function of strain, while the r-values of the specimens compressed in the II stage region (\dotε=0.0325/sec, ε=<0.062, n=1.006) become the decreasing function of strain after the maximum point at the ε=0.1.
    (3) The r-values of the specimens stretched in the TD direction in the II stage region (\dotε=0.0325/sec, ε=0.07) are constant for the whole strain regions and have no strain rate dependence.
    (4) The r-values of the specimens compressed in the II stage region (\dotε=38.3/sec, ε=0.07, n=0.855) are slightly affected by texture.
    Download PDF (3034K)
  • Michiko Hamasaki, Isao Gokyu, Shunichi Okamura
    1972 Volume 36 Issue 9 Pages 920-926
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The influence of work-history on the r-value has been examined on the pure aluminium and copper sheets having the cubic orientation.
    The results obtained are as follows:
    (1) The r-values of the Cu annealed specimens having the cubic orientation have neither texture anisotropy dependence nor strain rate dependence and are expressed by r=0.95 for the whole strain regions.
    (2) On the r-values of the Cu prestrained specimens pressed under conditions of \dotε=0.666/sec, ε=0.50 and n=0.336, the r-values of 0° and 90° directions to the rolling direction are expressed by r=e−0.05·\sqrtε. While the r-values of 0° and 90° directions have no strain rate dependence, but the r-value of 45° direction shows the strain rate dependence and are expressed by r=e0.006·ε0.27·\dotε0.02.
    (3) The r-values of the annealed specimens having the cubic orientation have no strain rate dependence and are expressed by r0=0.60, r45=0.90 and r90=0.50 for the whole strain regions.
    (4) On the r-values of the Al prestrained specimens pressed with conditions of \dotε=0.653/sec, ε=0.50 and n=0.283, the r-values of 0° and 90° directions to the rolling direction are expressed by r=1.747·ε+0.239. While, this r-values of 0° and 90° directions have no strain rate dependence, but the r-value of 45° direction shows the strain rate dependence and are expressed by r=3.56·\dotε+0.43·ε+0.118.
    Download PDF (2029K)
  • Akira Adachi, Yoshikiyo Ogino, Masaji Shiraishi
    1972 Volume 36 Issue 9 Pages 927-933
    Published: 1972
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Viscosity of liquid Pb-Sn alloys has been measured by the oscillating crucible method in the temperature ranges from the liquidus to about 800°C. By a careful experiment, it has been possible to obtain results which are accurate to within ±1.0 pct. The variation of viscosity with temperature followed the Arrhenius-type equation: η=AexpERT. The composition dependence of viscosity at constant temperature and of the activation energy for viscous flow has shown a small minimum at the eutectic composition (26.1 at%Pb). These anomalous behaviors suggest that a certain structural change may take place by the composition of liquid Pb-Sn alloys.
    Download PDF (2398K)
feedback
Top