巻号一覧
37 巻, 2 号
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堀 仁, 平野 賢一1973 年 37 巻 2 号 p. 135-141
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーThe precipitation process in the concentrated Al-Zn alloy (20∼80 wt%Zn) was investigated by means of electrical resistivity measurements and thermal analysis to elucidate it in relation to the solvus curves for the metastable phases, especially for the G.P.zones reported by previous workers. In consequence, a new solvus curve for the G.P.zones was proposed. The results obtained are as follows:
(1) The solvus curve for the G.P.zones determined by the present work does not coincide with those reported by the previous workers. It is shown that the solvus curve for the G.P.zones is located above the α-α′ miscibility gap by about 50°C.
(2) One of the solvus curves for the metastable phases which was reported to be located under the α-α′ precipitation line by about 25°C does not correspond to the correct solvus curve, but it represents only the temperature under which the α′ phase can precipitate remarkably. Another solvus curve which was reported to be located in the temperature range from 100 to 230°C corresponds to the reversion temperature of the G.P.zones formed during quenching or rapid cooling. However, it is not reasonable to regard the reversion temperature of the G.P.zones simply as the solvus temperature for them, because the reversion temperature is easily affected by the thermal stability of the G.P.zones.
(3) The precipitation process in the Al-Zn system can be explained by taking into account only the solvus curve for the G.P.zones and by regarding the G.P.zones as the precipitates which are coherent with the matrix lattice.抄録全体を表示PDF形式でダウンロード (680K) -
堀 仁, 平野 賢一1973 年 37 巻 2 号 p. 142-148
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーA solvus curve for the G.P.zones in Al-Cu alloys has been determined mainly by means of electrical resistivity measurements to elucidate the mechanisms of the formation of the G.P.zones from the thermodynamical point of view.
The electrical resistivity of the specimens has been measured continuously during cooling and heating between the α phase region and room temperature. As in the case of Al-Zn alloys, it has been found that once the G.P.zones are formed, in Al-Cu alloys, the electrical resistivity becomes higher than the value of the homogeneous solid solution and also that the G.P.zones are formed so fast that it is impossible to prevent the formation by the ordinary quenching methods. The temperature for the initiation of the G.P.zones formation during cooling should be regarded as the solvus temperature for the G.P.zones.
The solvus temperature for the G.P.zones thus determined does not coincide with the previous experimental results but fairly well with the results of a theoretical treatment by Meijering.
The present results suggest that the formation of the G.P.zones can be explained by referring to the free-energy versus concentration curve of the α phase in the same way as in the case of Al-Zn alloys and that the G.P.zones can be regarded as the coherent precipitates with the same structure as the matrix phase but with a different solute concentration from the matrix phase.抄録全体を表示PDF形式でダウンロード (635K) -
杉本 克久, 沢田 可信1973 年 37 巻 2 号 p. 148-155
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーThe corrosion potentials of binary aluminum alloys (Al-0.5% Fe, Al-0.5% Ni, Al-0.5% Mn and Al-4% Cu) and the polarization curves of pure aluminum (99.999% Al) and aluminum intermetallic compounds (Al3Fe, Al3Ni, Al4Mn and Al2Cu) have been measured in 1 mol solutions of H2SO4, NaCl, Na2SO4 and NaOH. The binary alloys were heat-treated at proper temperatures in order to precipitate intermetallic compounds, so that the resulting phases are the aluminum matrix and intermetallic compounds. The corrosion morphology of the alloys containing a small amount of intermetallic compounds was discussed on the basis of the differences between the dissolution rates of pure aluminum and the intermetallic compounds at the potentials coresponding to the corrosion potentials of the binary alloys.
The corrosion morphology of the binary alloys tested can be classified into the following four types according to the kinds of solutions used: (1) The intermetallic compounds are attacked preferentialy with an acid solution, (2) the intermetallic compounds undissolved remain on the specimen surfaces in an alkaline solution, (3) the pitting corrosion breaks out around the intermetallic compounds in a neutral solution with chloride ions and the intermetallic compounds will remain in corrosion pits because the dissolution rate of these compounds is lower than that of the pitting corrosion of the matrix phase, and (4) no apparent changes by corrosion occur in a neutral solution without chloride ions because of the very small dissolution rates of both the matrix and the intermetallic compound phases.抄録全体を表示PDF形式でダウンロード (700K) -
梅村 晃由1973 年 37 巻 2 号 p. 156-164
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーThe purpose of the present paper is to theoretically calculate the solidification process of alloy castings. The equations of the rate of the reactions and the conservations of mass and energy have been derived by expressing the solidification process of binary alloy, in which only primary crystals are solidified, in terms of two reactions, A (in liq.) =A(in sol.) and B(in liq.)=B(in sol.), and also by regarding it as a process of growth of crystals dispersed in the melt. These equations transform into the foundamental equations which describe the solidification process of a binary alloy casting when the related properties are given as known functions of temperature and concentration. In the present paper most of the properties are regarded to be constant. But, the activities and partial enthalpies of the components are estimated from the phase diagram on the assumption that Raoult’s law is valid in solid and Henry’s law in liquid. The foundamental equations consisting of four simultaneous non-linear partial differential equations have four unknown functions, that is, temperature, concentrations in solid and in liquid and fraction of solidification.
As an example of the calculation, a solidification process of an Al-4.5% Cu plate in the metal mold has been calculated by the finite difference method, and distributions of temperature, concentration and fraction of solidification, and their variations with time have been obtained. These data indicate a mush mode of the solidification, the near-equilibrium condition of concentration and temperature, and less segregation than expected. The motion of the liquid phase and the behavior of the nucleus, which are neglected in the present calculation, may have a great influence on the mode of solidification and on the segregation.抄録全体を表示PDF形式でダウンロード (698K) -
頓田 英機, 北島 貞吉, 梅江田 弘也1973 年 37 巻 2 号 p. 164-172
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーHighly perfect copper crystals with average dimensions of 5×5×50 mm were prepared by thermal cyclic annealing. The density of grown-in dislocations was about 103/cm2 and none or few of sub-grain boundaries were observed. Detailed observations of the dislocation motion and multiplication were carried out in connection with the stress-strain curves at the stress levels before and after the macroscopic yielding, using an etch pit technique. The main results are as follows.
(1) The dislocation mobility at a low stress level was much higher than those obtained by other workers but decreased with elevating stress level. (2) Dislocation multiplication occurred abruptly in a wide region of crystals, resulting in rushing into a sharp yielding in contrast with the results by others. (3) The macroscopic yield stresses (=dislocation multiplication stress) were settled down at a nearly constant value of 10.5±1.5 g/mm2.
The yielding mechanism is discussed in terms of the propagation of dislocation multiplication onto the other parallel slip planes by elastic interactions between the dislocation groups from a certain trigger source and new sources.抄録全体を表示PDF形式でダウンロード (1099K) -
辻本 得蔵, 斎藤 一男1973 年 37 巻 2 号 p. 173-178
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーSide-bands of Cu-4% Ti alloy have been examined in detail by means of X-ray analysis using a Guinier camera. The side-bands become stronger and sharper with the increase of aging time t. Side-bands formed at below 450°C (termed the early stage side-bands) approach the main lines kept at a fixed position with the progress of aging. On the other hand, side-bands formed at above 500°C (termed the later stage side-bands by the present authors) do not move, but the main lines move to the high-angle side.
The features of the early stage side-bands are as follows: The quantities Q, which are caluculated from the angle Δθ between the main line and the side-band by using the formula Q=h·tanθ⁄(h2+k2+l2)·Δθ, increase in proportion to logt. The intensities of side-bands I increase in proportion to logt. The half widths of side-bands W decrease in proportion to logt. The relations QH>QL, IH>IL and WH<WL are obtained. Here the subscript H or L indicates that the values are those for the high- or low-angle side-bands, respectively. The asymmetry QH⁄QL increases linearly with the increase in Q and the WH⁄WL decreases, irrespective of aging temperature. The IH⁄IL increases linearly with the increase in Q in a rate, which is higher at low temperatures.抄録全体を表示PDF形式でダウンロード (522K) -
辻本 得蔵, 斎藤 一男1973 年 37 巻 2 号 p. 179-185
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーEarly stage side-bands is observed on a X-ray diffraction photograph of a Cu-4%Ti alloy aged at 350∼500°C. In this stage the side-bands approach main lines with progress of aging and the asymmetry in position, intensity and half-width of the side-bands becomes intense. In the present paper, a model for the concentration distribution of solution, which brings about such anormalous diffraction effect, is discussed.
From the theoretical treatment for diffraction from the solid solution with a concentration variation, it is concluded that the asymmetry of side-bands cannot be explained by a model for the sharply periodic distribution of the “unit region of concentration variation” (abb. “unit region”), and that the decrease in distance between side-band and main line with aging cannot be explained by a model of the random distribution of “unit region”. A new model of the distribution of the “unit region” with diffuse periodicity is proposed. It is shown that the changes in position, intensity and configuration of the side-bands by aging, and the time or temperature dependence of their asymmetries can be well explained by this model, if a zone-complex is chosen as the “unit region”.抄録全体を表示PDF形式でダウンロード (581K) -
福島 英二, 後藤 昭, 伏見 光造1973 年 37 巻 2 号 p. 186-190
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーA Load-elongation curve of 18-8 stainless steel was obtained at −269°C with an extensometer specifically made for cryogenic use. The role of martensitic transformation in the serrations was discussed from the results of strain and hardness distribution measurements, X-ray analysis and optical microscopic observation of surface relieves. The change in electrical resistivity with the increase of tensile strain was also measured at −269°C with the specimen of different shape prepared from the same material, and the cause of the overshoots observed in the electrical resistivity change was also discussed. The results are summarized as follows:
(1) The serrations observed were large in general except for those at the very early stage of the deformation. The plastic deformation component, i.e. a slight deviation from a straight line, was observed at the upper part of the load increasing portions of the serrations.
(2) The serrations in the yielding and uniform elongation regions occurred with localized plastic deformation of the specimen. The deformation was accompanied by martensitic transformation.
(3) The over-shoots were observed in the electrical resistivity changes, which took place discontinuously with load drops at the serrations. The main cause for these overshoots was considered due to heat generation accompanied by martensitic transformation (γ→α′).抄録全体を表示PDF形式でダウンロード (586K) -
小山 伸二, 石井 照朗, 成田 貴一1973 年 37 巻 2 号 p. 191-196
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーThe solubility products of vanadium carbide and nitride in ferritic iron of Fe-V-C and Fe-V-N systems were studied in the temperature range from 700 to 800°C. The specimens, after solution treating and subsequent quenching into ice water, were heat-treated in the ferrite range to precipitate the vanadium carbide or nitride sufficiently. The contents of dissolved carbon, nitrogen and vanadium in these specimens were determined by the internal friction measurement and chemical analysis respectively. As the results, the solubility products are represented by the following equations;
(This article is not displayable. Please see full text pdf.)
\ oindentThese results show that solubility preducts of vanadium carbide and vanadium nitride in ferritic iron come to the lower value of about one-tenth than those in austenitic iron, and that the solubility product of vanadium carbide in ferritic iron is about one hundred times greater than that of vanadium nitride.抄録全体を表示PDF形式でダウンロード (509K) -
岡田 秀彌, 細井 祐三, 阿部征三郎 , 山本 州一1973 年 37 巻 2 号 p. 197-203
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーThe fracture mode of several austenitic stainless steels in stress corrosion cracking in MgCl2 aqueous solution was investigated fractographically by scanning electron microscopy. Effects of alloying elements, testing temperature, anodic and cathodic polarization, and passivator on the fracture mode were determined. With the exception of the alloys containing Mo, transgranular fracture was observed in stress corrosion cracking of austenitic stainless steels in MgCl2 aqueous solution boiling at 143°C. Transgranular fracture was characterized by a fine parallel pleat pattern. This pattern seemed to be traces of dissolution of the metals. Intergranular stress corrosion cracking occurred in Type-316 stainless steel and 16 Cr-15 Ni-2∼4 Mo steels. This type of fracture was also observed in Type-304 stainless steel fractured under the following conditions; testing temperatures lower than 125°C, cathodic polarization, and addition of NaNO3. The transgranular fracture surface was found to be parallel to {111} planes.抄録全体を表示PDF形式でダウンロード (1636K) -
鈴木 寿, 棚瀬 照義, 林 宏爾1973 年 37 巻 2 号 p. 204-208
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーTwo kinds of alloys, i.e., usual WC-7% Co alloy stressed to fracture under compression and a strain-free WC-10% Co alloy (standard alloy) carefully prepared were used as specimens. The changes in the dislocation structure of carbide in the fractured alloy by annealing were studied comparing with the structure in strain-free carbide in the standard alloy by transmission electron microscopy. Moreover, X-ray studies on the recovery of strained carbide powder and of strained carbide near the ground surface of standard alloy were also carried out.
The results showed that the strain introduced into carbide in the fractured alloy recovered rapidly when the annealing temperature exceeded about 1200°C, and that the strain almost disappeared by annealing at 1400°C for about 15 min. The results of X-ray analysis agreed fairly well with the above results.抄録全体を表示PDF形式でダウンロード (1075K) -
落合 庄治郎, 水原 誠, 村上 陽太郎1973 年 37 巻 2 号 p. 208-215
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーTensile tests have been carried out in order to clarify the deformation and fracture behaviours of the composites of tungsten or molybdenum fibres uniaxially aligned in copper and copper-chromium alloy matrices prepared by vaccum infiltration technique. The factors affecting the elongation and tensile strength of the composites were discussed in detail from a comparison of the behaviours of the individual composites. The results obtaind for W/Cu and Mo/Cu composites were in general, in agreement with the previous reports. It was found that the fracture of W/Cu-Cr alloy composites occurred in an elastic region of a tungsten fibre, and the elongation and tensile strength of the composites showed lower values than those of W/Cu. This mode of fracture can be explained in terms of a notch effect of a tugsten fibre caused by the breakage of a W-Cr solid solution layer formed at the fibre-matrix interface and a poor notch resistance of the composite arising from stronger bonding between fibre and matrix. Moreover, the deformation behaviour was confirmed to obey the rule of mixtures in which the constraint arising from the different lateral constractions between fibre and matrix is considered. On the other hand, the tensile and yield strengths of age-hardened Mo/Cu-Cr alloy composites were found to show higher values than those of Mo/Cu ones by the ageing treatment, because of the hardening of the matrix and the absence of detrimental effects of a Mo-Cr solid solution layer formed at the interface.抄録全体を表示PDF形式でダウンロード (1077K) -
森戸 延行, 末高 洽1973 年 37 巻 2 号 p. 216-221
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーUltraviolet high sensitivity reflection spectra of the copper electrode surface have been measured in situ under the potentiostatic polarization in 3% NaCl aqueous solution. In the deaerated nearly neutral 3% NaCl solution containing 0.0002 M BTA (benzotriazole), BTA-Cu (I) (benzotriazole-cuprous salt) film was formed on copper and did not diminish by cathodic polarization, but at pH 3 the formation of BTA-Cu (I) film was not found. These behaviors can be explained as follows; The reaction (1), Cu++BTA\ ightleftharpoonsBTA-Cu (I)+H+, proceeds to the right hand side of the equation in the nearly neutral solution, and in acidic (pH 3), to the left. This is because the concentration of BTA-Cu (I) is a function of pH as shown by Eq. (2)
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\ oindentwhere K is an equilibrium constant of Eq. (1).
The polarization curves showed that BTA inhibited mainly the anodic reaction and in the cathodic region the retardation of hydrogen evolution was more effective than that of the oxygen reduction. The corrosion reaction was much more markedly inhibited in the nearly neutral than in the acidic solutions. It is concluded that the inhibition is due to the protection of BTA-Cu (I) film, but not due to the chemisorbed BTA film.抄録全体を表示PDF形式でダウンロード (445K) -
高田 新三1973 年 37 巻 2 号 p. 222-227
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーSevral works on the cast R-Cu-Co series permanent magnets have already been reported. In this investigation, from the practical standpoint, experiments were carried out for R-Cu-Co ternary alloys which had been oriented by the chilling process. The specimens were heated between 300 and 1200°C for 1 hr in Ar flow, and the variations in magnetic properties, micro-structures, etc, of the specimens furnace cooled or air quenched were investigated. The results are summarized as follows:
(1) In the cast state, specimens of the ternary composition (Ce-MM)CuCo4 exhibited the most remarkable chill effect, that is, 4πIr⁄4πI10K=0.96 and (BH)max=5.5 MG·Oe.
(2) When compared the furnace cooled specimens with the air quenched specimens for the annealed state, the specimens air-quenched from 500°C showed the most excellent permanent magnet properties, that is, 4πI10K=5450 G, 4πIr=5200 G, IHC=5600 Oe, BHC=3700 Oe, (BH)max=6.0 MG·Oe.
(3) The specimens annealed at temperatures above 800°C showed snaky-type hysteresis curves. In the specimens water-quenched from these temperatures, the Ce2Co17 phase as well as the CeCo5 phase was newly detected by X-ray diffraction. This is considered as a cause for these hysteresis curves to precipitate the Ce2Co17 phase.抄録全体を表示PDF形式でダウンロード (747K) -
菊池 潮美, 梶谷 幹男, 圓城 敏男, 足立 正雄1973 年 37 巻 2 号 p. 228-234
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーThe high-temperature steady-state creep behavior of Cu and Cu-Al solid solutions containing 2.5 and 15 at% Al was studied in the temperature range from 450 to 700°C. The results obtained are as follows: (1) The steady-state creep rate \dotε can be represented as a power of stress σ according to \dotε∝σn, and the value of n is about 9 for pure copper and about 5 for Cu-Al solid solutions. The steady-state creep rate also can be represented as a function of the mean effective stress \barσ*, namely \dotε∝\barσ*n*, and the value of n* is about 5 for pure copper and about 3.5 for Cu-Al solid solutions. (2) The mean internal stress \barσi at steady-state creep determined by the stress dip test depends on the applied stress, concentration of solute atoms and temperature. The value of \barσi⁄σ decreases with the applied stress and temperature, and increases with the concentration of solute atoms. (3) The activation area A* is a function of the mean effective stress \barσ* and A*\barσ*=const. The activation area does not depend on the concentration of solute atoms. (4) The steady-state creep rate increases with stacking fault energy γ, following an emprical relation of the form \dotε∝γm, and m is 1.1∼1.4 for Cu-Al solid solutions.抄録全体を表示PDF形式でダウンロード (560K) -
山田 義人, 上村 税男, 杉原 真1973 年 37 巻 2 号 p. 235-241
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーIn order to obtain well-qualified square hysteresis loop magnetic material, cold rolled Fe-Mn-Co alloys have been investigated. The effects of aging, composition and cold rolling on magnetic properties have been studied.
These alloys indicate the best magnetic properties, when they were heat treated at 400∼500°C for 1 hr. Mn raises Hc, but lowers Br and 4πIm, and Co raises Hc, Br and 4πIm. However, the adequate content of Mn is less than 14%, because, with increasing the amount of Mn, the value of 4πIm becomes too low, although increasing Hc. The Co content of less than 30% is appropriate because the workability of the alloys is deteriorated beyond it.
If the intermediate heat treatment is given before cold rolling, the magnetic properties are improved.
The properties obtained are, for instance, Br=17700∼16000 G, Hc=27∼45 Oe and Ir⁄Im=86∼91%, or Br=12700 G, Hc=72 Oe and Ir⁄Im=90%, with fairly good workability.抄録全体を表示PDF形式でダウンロード (550K) -
迎 静雄, 藤原 諒1973 年 37 巻 2 号 p. 241-246
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーFrom the strain rate cycling tests, m* (the stress exponent of dislocation velocity) in Fe, Fe-0.05% Mn and Fe-3% Ni were evaluated over the temperature range of 125 to 342°K and some grain sizes. In the evaluation of the m* values, the following four methods were used; mε* was obtained from extrapolating ε and d−1⁄2 to zero, m0* from the activation energy-temperature curves, \barm* from the mean strain rate-stress sensitivity and mH* from the partial differentiation of Seeger’s equation, considering Hk as a function of thermal stress coponent τ*. The results obtained are as follows:
(1) The values of mε*, m0* and \barm* are nearly equal in Fe-0.05% Mn.
(2) Materials having weaker temperature dependence of mT*−m253°K* have excellent ductility in low temperature range.
(3) The temperature dependence of (mH*)T−(mH*)253°K is greatly affected by −∂Hk⁄∂lnτ* values.抄録全体を表示PDF形式でダウンロード (417K) -
木村 啓造, 上原 重昭1973 年 37 巻 2 号 p. 247-251
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーMechanical properties and microstructures of heat-treated zirconium-ruthenium and zirconium-palladium dilute alloys were studied.
Strength and hardness of annealed Zr-Ru and Zr-Pd alloy increase with increasing amount of Ru or Pd up to about 1 at% or 0.5 at%, respectively. Within the addition of 1 at% Ru or Pd, elongation is above 30% in the tensile test and the ductility of Zr is not affected by the addition of Ru or Pd. The hardness of the alloys quenched from the β region shows higher values than those of the annealed alloys. Age-hardening is observed in the quenched alloys and most remarkably in the Zr-1 at% Ru alloy.
The structures of the quenched alloys are martensitic. In the primary martensite plate, (10\bar11) microtwins are mainly observed, with dislocations and (10\bar12) microtwins. But in the secondary martensite plate, (10\bar11) microtwins cannot be observed. In the microstructures of the quenched and aged alloys, preferred precipitates are observed on the grain boundaries and twin boundaries.抄録全体を表示PDF形式でダウンロード (853K) -
植村 治, 竹内 栄1973 年 37 巻 2 号 p. 252-255
発行日: 1973年
公開日: 2008/04/04
ジャーナル フリーThe magnetic susceptibility χ in liquid Ag-Ga, Cu-Ga, Cu-Ge and Cu-Bi systems was measured by the Faraday method over a wide composition range. And the temperature change of χ in liquid Ag-Ga, Cu-Ga and Cu-Ge systems was also measured over a temperature range from about 500 to 1000°C. Results obtained were summarized as follows: (1) The diamagnetic peak in the Ag-Ga, Cu-Ga and Cu-Ge systems was found in the high noble metal composition range, (2) the temperature change of χ became large near the composition where the diamagnetic peak was found, and (3) χ in the Cu-Bi system showed the composition dependence similar to that in usual liquid alloys.
It was shown from above results that only the Cu-Bi system obeyed the free electron model. From the comparison with the heat of mixing and the phase diagram in these systems, it appears that the diamagnetic anomaly of the three alloy systems is caused by the formation of clusters related to electron compounds existing in the solid state.抄録全体を表示PDF形式でダウンロード (238K)
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