巻号一覧
69 巻, 8 号
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宮崎 修一, 古屋 泰文, 佐久間 利雄, 西 義武, 細田 秀樹2005 年 69 巻 8 号 p. 567
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーPDF形式でダウンロード (150K) -
佐久間 俊雄, 三原 祐二, 越智 保雄, 山内 清2005 年 69 巻 8 号 p. 568-574
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーIn many cases that shape memory alloys are applied to the engineering and medical fields, it is necessary to deform them in martensitic phase. However, if the slip-deformation occurs, shape recovery does not occur completely even if heated up above Af. It is reported that transformation temperatures are changed by pre-deformation and in constrained strain condition. Therefore, it is important to investigate the relationship between the pre-deformation and the deformation and transformation characteristics such as recovery stress, transformation temperatures and so on. The purpose of this work is to clarify the influence of pre-deformation on recovery strain, recovery stress and transformation temperatures in a Ti-Ni alloy. The specimens are Ti-50 at%Ni annealed at 1103 K for 60 s. The variation of recovery strain, recovery stress and transformation temperatures by pre-straining is investigated experimentally. The variation of transformation and deformation behavior by pre-straining will be discussed in relation to the volume fraction of slip-deformed martensite.
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佐久間 俊雄, 三原 祐二, 遠山 寛匡, 越智 保雄, 山内 清2005 年 69 巻 8 号 p. 575-580
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーIt is reported that the transformation characteristics of Ti-Ni shape memory alloys are influenced by manufacturing conditions, such as composition, heat-treatment temperature, cold working, and so on. To understand correctly the effects of these manufacturing conditions on transformation characteristics of Ti-Ni shape memory alloys make it possible to control the transformation temperature and recovery stress. The purpose of this work is to clarify the effect of cold working ratio on transformation and deformation behavior after pre-deforming shape memory alloy. The specimens were Ti-50 at%Ni annealed at 673 K for 3.6 ks. The variation of the recoverable strain, recovery stress and transformation temperature with cold working ratio was investigated experimentally. The solution treated material was also used as a reference material. The effect of cold working ratio on the transformation and deformation behavior will be discussed in relation to the residual martensite volume fraction subjected to slip deformation.
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佐久間 俊雄, 三原 祐二, 越智 保雄, 山内 清2005 年 69 巻 8 号 p. 581-586
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe modeling of the transformation and deformation behavior of a shape memory alloy has been investigated in various researchers. However, there are few reports that investigated plastic deformation of shape memory alloys. In case an actual product is designed, the modeling in consideration of plastic deformation is indispensable. In this work, plastic deformation after pre-deformation is considered using the volume fraction of slip-deformed martensite. New kinetics and constitutive equations for the reverse transformation process are proposed. The material constants in the proposed equations are determined from the results of tensile and heating/cooling tests on Ti-50 at%Ni alloy. The calculated results describe well the deformation and transformation behavior affected by pre-strain.
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岡部 永年, 仙波 浩雅, 山地 徹, 沖田 圭介, 山内 清2005 年 69 巻 8 号 p. 587-595
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーAttempts have been made to develop new types of seismic devices using shape memory alloys. They are a single-stage bellows which are processed from thin-walled tubes by employing the rubber bulge method and then are annealed at 400°C for the shape-memory treatment. As strain distribution is induced on the bulged part due to the process, it is significant to know the effects of pre-strain and the subsequent heat-treatment on the mechanical properties of the material for tube when designing the bellows shapes for the seismic structures. Thus, tensile tests and thermal analysis were conducted before and after the heat treatment on rectangular specimens cut from the tubes.
In this paper, the oxidization method was first attempted to observe distinctively both regions of the stress induced martensite (SIM) transformation and twin deformation generated while applying strain to the specimens. It became clear that the micro-structure in the SIM area had a changed R phase from the austenite phase at room temperature after being annealed at 400°C. From the experimental and analytical results for the specimens, the mechanical behavior was classified broadly into two conditions as follows: (1) the mechanical behavior can be formulated on the basis of a series-model consisting of areas of both R phase and austenite considering the area-ratio of these phases until the SIM transformation has expanded over the whole specimen, and (2) after that, the mechanical behavior can be formulated using the exponential function for the applied strain as a parameter.
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村澤 剛, 米山 聡, 佐久間 俊雄, 隆 雅久2005 年 69 巻 8 号 p. 596-603
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーMany problems have existed in usage of shape memory alloy (SMA) such as the appearance of unexpected deformation behavior under complicated thermo-mechanical loadings. Inhomogeneous deformation behavior of SMA is one of the causes in those problems. The aim of the present paper is the investigation of inhomogeneous deformation behavior arising in SMA during cyclic loading. Firstly, a test system measuring inhomogeneous deformation behavior was constructed on the basis of Digital Image Correlation (DIC). Secondary, measurements of inhomogeneous deformation behavior (local strain distribution) arising in 50.5Ni49.5Ti plates were conducted during cyclic tensile loading-unloading at the temperature region of pseudoelasticity. It was seen that inhomogeneous deformation behavior sensitively changed according to state of loading (i.e., number of cycle, history of loading and so on). Also, macroscopic deformation behavior was strongly affected by inhomogeneous deformation behavior. It is very important for application of SMA to investigate the relationship between macroscopic deformation behavior and inhomogeneous deformation behavior.
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北村 一浩, 口田 敏雄, 稲葉 忠司, 徳田 正孝, 吉見 幸春2005 年 69 巻 8 号 p. 604-607
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe shape memory properties of a cast Ti-Ni shape memory alloy (SMA) were studied. Base materials were prepared as a melting method ingot and a self-propagating high-temperature synthesis (SHS) ingot. The composition of these ingots was Ti-50.5 at%Ni. Each ingot was cast into a rod shape by centrifugal casting. The heat-treatment conditions were 773 K for -1.8 ks and 873 K for -3.6 ks. Shape memory characteristics were measured by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and a tensile test. All cast specimens have good shape memory characteristics. According to DSC measurements, the specimens made by melting show gravity segregation.
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水内 潔, 井上 漢龍, 杉岡 正美, 伊丹 正郎, 浜田 賢一, 川原 正和2005 年 69 巻 8 号 p. 608-613
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーMagnesium alloy matrix composite reinforced by continuous TiNi shape memory alloy (SMA) wire was fabricated by Pulsed Current Hot Pressing (PCHP) of TiNi SMA wires sandwiched with a pair of AZ31 Mg alloy plates, and its microstructure and mechanical properties were examined. The Mg alloy plates with 20 vol.% of the TiNi wires were readily hot pressed into a composite at the temperature of 773 K for a total processing time of 0.6 ks. During the processing, the thickness of the preform composed of Mg plates and TiNi wires decreased drastically at the temperature between 400 K and 650 K, resulting in the bonding between the wire and the matrix plates. As a reaction occurred insubstantially in the vicinity of the boundary between Mg alloy plates and TiNi wire, no homogeneous interfacial reaction layer was formed. The tensile yield stresses of the composite deformed in tension at 373 and 423 K were higher by about 68 MPa and 87 MPa than that at 293 K, respectively. At the test temperature range, both the yield stress and elongation of the composite increased with increasing temperature. At temperatures higher than 373 K, the specific strength of the composite was higher than that of AZ31 Mg alloy.
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長 弘基, 金 宰逸, 金 熙榮, 宮崎 修一2005 年 69 巻 8 号 p. 614-621
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe shape memory properties of sputter-deposited Ti-Ni thin films crystallized from amorphous at low-temperatures, 60-90 K lower than the crystallization peak temperature measured by differential scanning calorimetry (DSC), were investigated. The Ti-47.7 at%Ni (Ti-rich) and Ti-51.6 at%Ni (Ni-rich) thin films were fabricated by a r.f. magnetron sputter-deposition method. Heat-treatment temperature was varied from 643 to 693 K and heat-treatment time was varied from 3.6 to 360 ks. Thin plate precipitates were formed on {100}B2 in the Ti-rich thin films heat-treated at 653 K. Maximum recovery strain (εAmax) of the Ti-rich thin films increased up to 5.4% with increasing heat-treatment time. But it started to decrease after reaching the maximum value. The decrease in εAmax was caused by the decrease of the critical stress for slip (σs) with increase of heat-treatment time because of the growth of thin plate precipitates. Ti3Ni4 precipitates were formed in the Ni-rich thin films heat-treated at 673-693 K. εAmax of the Ni-rich thin films increased with increasing heat-treatment time. But, the εAmax reached only 2.9%, since the martensitic transformation and the growth of martensites were strongly suppressed by Ti3Ni4 precipitates. The martensitic transformation temperature (Ms) of the Ti-rich and Ni-rich thin films increased with increasing heat-treatment time.
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～二方向ひずみに及ぼす付加ひずみの影響～沖田 圭介, 岡部 永年, 佐藤 智之, 中尾 考志2005 年 69 巻 8 号 p. 622-627
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーA promising field for application of shape memory alloys (SMAs) in the near future is in micro-actuator technology. Two-way shape memory effect (TWSME) is particularly suitable for application in actuators, since pre-determined responses can be obtained very easily by thermal changes to shape memory elements.
In this paper, the TWSME, Ti-Ni-Nb alloy, was investigated quantitatively by applying various levels of pre-deformation. Deformation in a complete martensite phase was applied as a thermomechanical treatment in order to obtain the two-way memory strain. The experimental results indicated that the deformation mechanism in martensite phase was martensite orientation accompanied by dislocation slip. The dislocation due to the slip deformation is the origin of the internal stress field that is necessary to generate the two-way memory strain. However, excessive introduction of dislocation tends to decreases the two-way memory strain. The maximum two-way memory strain observed in this experiment was 2.1% at an applied strain of 18%. In addition, pre-deformation increases the temperature of reverse transformation, but decreases the temperature of martensitic transformation. These experimental results can be explained by using the series-parallel combined model suggested in our previous study.
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稲邑 朋也, 高橋 洋平, 細田 秀樹, 若島 健司, 永瀬 丈嗣, 中野 貴由, 馬越 佑吉, 宮崎 修一2005 年 69 巻 8 号 p. 628-633
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーMartensitic transformation behavior and shape memory properties of Ti50Ni40Pt10 (TiNiPt) melt-spun ribbons fabricated by a single roll melt-spinning technique were characterized. The constituent phases of the as-spun ribbon were B2 (parent phase) and B19 (martensite phase) at room temperature. The B2-B19 martensitic transformation temperatures of the as-spun ribbon were 100 K higher than those of the bulk-material with the same chemical composition. The martensitic transformation temperatures of the as-spun ribbon were decreased with increasing the temperature of the heat-treatment made after the melt-spinning. As-spun ribbon and the heat-treated ribbons exhibited shape recovery by heating and/or pseudoelasticity. The martensitic transformation temperatures determined from the temperature dependence of the 0.2% flow stress of the pseudoelastic deformation were in good agreement with those of B2-B19 martensitic transformation determined by DSC. It was confirmed that the observed shape recovery and pseudoelasticity are shape memory effect and superelasticity, respectively, due to the B2-B19 martensitic transformation.
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御手洗 容子, 原 徹, 三浦 誠司, 細田 秀樹2005 年 69 巻 8 号 p. 634-642
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーIt is known that some of platinum group metals base intermetallics have shape memory effect. We note PtTi because its phase transformation temperatures is at around 1273 K. The phase transformation of PtTi and the effect of Ir on the phase transformation were investigated by X-ray diffractometry (XRD), differential thermal analysis (DTA), in-situ surface observation in laser microscope, and microstructure observation in transmission electron microscopy (TEM). The shape recovery was investigated by dilatometry. Microstructure suggests martensitic phase transformation occurs in PtTi and (Pt, Ir)Ti. The shape recovery was found in some of the tested alloys. Potential of platinum group metals base intermetallics as high temperature shape memory alloys is discussed in this paper.
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上野 孝史, 久保田 健, 岡崎 禎子, 古屋 泰文2005 年 69 巻 8 号 p. 643-648
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーFerromagnetic Co-Ni alloys of less than 35 at%Ni exhibit a phase transformation from γ-phase (FCC) to ε phase (HCP): both phases are stable at higher and lower temperatures, respectively. Since both phases of these alloys exhibit high magnetization and thermoelastic martensitic transformation, it is expected as new ferromagnetic shape memory alloy. In this study, We prepared a rapid-solidified Co-32 at%Ni foil and analyzed thermoelastic and stress-induced martensite phase in temperature range of 77 to 673 K from observation of the texture, structure, magnetic property and Barkhausen noise. From these results, it is found that 1) the thermoelastic martensitic transformation is not reversible and 2) a stress-induced martensite phase is transformed to a austenite phase by heating. The result is caused by the mechanism of the transformation from a γ phase (HCP) to a ε-phase (FCC).
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阪本 辰顕, 福田 隆, 掛下 知行2005 年 69 巻 8 号 p. 649-653
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーWe have investigated the uniaxial magnetocrystalline anisotropy constant Ku and the stress required for the rearrangement of martensite variants τreq in a disordered Fe-31.2 mol%Pd ferromagnetic shape memory alloy. The value of |Ku| is obtained from the area enclosed by two magnetization curves (along the easy and hard axes) to be 180 kJ/m3 at 77 K and 80 kJ/m3 at 200 K. The maximum of magnetic shear stress τmagm acting across the twinning plane under the [001]P field is evaluated as the magnetocrystalline anisotropy constant |Ku| divided by the twinning shear s; it is 1.5 MPa at 77 K and 1.6 MPa at 200 K. The value of τreq is evaluated by tensile tests to be about 0.9 MPa at 80 K and about 0.6 MPa at 200 K. Comparing τmagm and τreq, we can quantitatively explain the reason for the rearrangement of martensite variants by magnetic field in this alloy.
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前嶋 貴士, 牛丸 智史, 山内 清, 西田 稔2005 年 69 巻 8 号 p. 654-658
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe effects of Sn content and aging conditions on superelasticity in Ti-Mo-Sn alloys were investigated. Martensitic transformation temperature decreased with an increasing of Sn content. A large superelastic strain of 3.0% was obtained in a solution-treated Ti-5 mol%Mo-5 mol%Sn alloy in the tensile test. The superelasticity in the Ti-5 mol%Mo-5 mol%Sn at room temperature was improved by aging at 873 K for short periods between 180 and 420 s. A specimen aged at 873 K for 300 s exhibited superelasticity with a recovery strain of 3.5% in the tensile test. A recovery strain of 3.0% was consistently achieved in cyclic tensile deformations.
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澤口 孝宏, 菊池 武丕児, 小川 一行, 梶原 節夫, 池尾 陽作, 小島 正朗, 小川 孝寿2005 年 69 巻 8 号 p. 659-662
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThis article reports the mechanical properties of the concrete prestressed by the Fe-Mn-Si-based shape memory alloys containing NbC that exhibit an excellent shape memory effect without so-called the “training” treatment. A thermomechanically treated Fe-28Mn-6Si-5Cr-0.53Nb-0.06C(mass%) alloy was used for this purpose. Four rectangular shaped-specimens were embedded in mortar, and heated at above their reverse martensitic transformation start emperature after hardening of the mortar matrix. Three-point bending tests were performed for the mechanical property characterization. It was found that prestressing by the shape memory alloys increased the bending stress and cracking stress of mortar.
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中尾 航, 長田 俊郎, 山根 一哉, 高橋 宏治, 安藤 柱2005 年 69 巻 8 号 p. 663-666
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーAlumina reinforced SiC particles and whiskers composites having high crack-healing ability and fracture toughness were prepared. The crack-healing behavior was systematically investigated. From the obtained results, the mechanisms of the composites were studied. For the crack-healing by SiC whiskers alone, partial bonds were formed by connecting between the crack surface and the bridging SiC whiskers. As a result, the crack-healed part has low reliability although the strength is sufficiently recovered by crack-healing. On the contrary, alumina/SiC particles/SiC whiskers multi-composite could form the crack-healed part having high reliability, as the space between the crack surfaces was completely filled with the formed oxide.
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竹内 光明, 松村 義人, 内田 裕久2005 年 69 巻 8 号 p. 667-670
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーMagnetostrictive properties of Ar ion-irradiated R-Fe(R: Tb, Sm) thin films were studied with respect to residual stress. Film samples were prepared by a magnetron sputtering. The film composition was Tb36Fe64 and Sm27Fe73 with amorphous structures. After the deposition, film samples were irradiated by Ar ions with an energy of 10 keV and a current density of 27-80×10-2 A/m2 up to 1×1022 ions/m2. Magnetostrictive susceptibility of the Tb36Fe64 film decreased with increasing ion current density by 55×10-2 A/m2, however, improved with high current density above 70×10-2 A/m2. Magnetostrictive susceptibility of Sm27Fe73 increased with increasing ion current density up to 55×10-2 A/m2. This was caused by increase of compressive stress induced by Ar ion irradiation with low current density and stress relaxation by increased temperature during irradiation with high current density. The magnetic properties were found profoundly influenced by stresses induced by competitive factors such as irradiation damage and thermal annealing effect.
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高橋 啓介, 増田 進吾, 津嘉山 葉, 門脇 睦, 松村 義人, 西 義武2005 年 69 巻 8 号 p. 671-675
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーSmFe2.2 alloy films were prepared by magnetron sputtering process. High magnetostrictive susceptibility was found under low residual gas pressure and low sputtering gas pressure at reduced substrate temperatures (Ts/K)/(Tm/K) from 0.30 to 0.37, where Ts and Tm are substrate temperature and melting point of SmFe2.2 alloy, respectively. The residual gas pressure dependence of magnetostrictive susceptibility was mainly explained by rate of samarium oxidation. Based on morphological change in Thornton's model, contributions of sputtering gas pressure and substrate temperatures were discussed.
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裘 進浩, 谷 順二, 折笠 和之, 松田 和也, 高橋 弘文2005 年 69 巻 8 号 p. 676-679
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThis study aims to fabricate high-performance lead-free piezoelectric materials by using a hybrid sintering process, which is a combination of microwave heating and hot-press. The hybrid sintering process was found to be able to improve the density and consequently the piezoelectric properties of PZT and PNN-PZT materials in the former study. The lead-free piezoelectric materials used in this study are BNBT-6[0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3]. The BNBT-6 was sintered with the hybrid process, the conventional process, the microwave process and the hot-press process and the piezoelectric properties of the acquired specimens were investigated and compared. The results showed that the hybrid process increased density of sintered specimens, but could not improve electromechanical coupling factors, kp and kt, and the dielectric constant ε33T/ε0, probably due to large grain size and the residual strain generated by the pressure during sintering.
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三林 浩二, 西尾 元気2005 年 69 巻 8 号 p. 680-683
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーAn enzymatic gas sensor (called “bio-sniffer”) for formaldehyde vapor was constructed by immobilizing formaldehyde dehydrogenase (FALDH) to hydrophilic polytetrafluoroethylene (H-PTFE) membrane with Platinum-coated electrodes. The platinum electrodes (300 nm) were formed by sputter deposition onto both sides of the H-PTFE membrane (thickness=80 μm, pore size=0.2 μm). The oxidation current of NADH (reduction form) being produced by FALDH enzyme reaction with NAD+ (oxidized form) could be measured by amperometric analysis between two Pt electrodes. The bio-sniffer was used to measure formaldehyde vapor with the calibration range from 40 to 3000 ppb, including the maximum permitted concentration of 80 ppb, with high selectivity being attributable to the substrate specificity of FALDH as gas recognition material.
By applying the FALDH sniffer for formaldehyde vapor from building timbers, the bio-sniffer could evaluate the concentration of formaldehyde, thus being in agreement with the results in the commercial available detector tube. The bio-sniffer with high gas selectivity would be effective and convenient non-invasive approach to evaluate the formaldehyde concentration in the gas phase.
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徳永 博文, 藤野 茂2005 年 69 巻 8 号 p. 684-690
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーHydroxyapatite dispersed glass coatings on Vitallium®, a cobalt-chromium alloy were prepared using a simple enameling technique. The composition of the bioinert glasses in the SiO2-B2O3-Na2O-K2O-MgO-Al2O3-ZrO2-TiO2 system has been tailored to match the thermal expansion of the alloys. The optimum glass composition and firing conditions (temperature and time) needed to fabricate homogeneous coatings with good adhesion to the alloy were determined. The final coating thickness ranged between 40 to 60 μm. Coatings fired under the optimum conditions do not delaminate during indentation tests of adhesion. Excellent adhesion to the alloy has been achieved through the formation of 200 nm thick interfacial layers (CrOx). X-ray diffraction patterns for the hydroxyapatite dispersed on the glass surface showed a strong preferred orientation of the (0 0 2) plane when immersed in a simulated body fluid (SBF).
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佐藤 彰洋, 横川 忠晴, 小泉 裕, 小林 敏治, 原田 広史2005 年 69 巻 8 号 p. 691-694
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーIt is important to clarify the parameters which influence the creep rupture life of Ni-base single crystal superalloys under the service condition of jet-engine turbine blades, such as 1000°C/245 MPa. In the most recently developed alloys, Ru is added to suppress the formation of the detrimental Topologically Close Packed (TCP) phases, however, its solid solution strengthening effects have not been clarified yet. In this study, the parameters affecting the creep rupture life of alloys with various compositions were analyzed by a multi regression method, and the results were discussed quantitatively in terms of the chemical composition of the γ′ phase, lattice misfit and volume fraction. It was found that Re, Mo, Ta and W were all effective additions for solid solution strengthening and Re was found to be the most effective under the service condition. In contrast, Ru addition had almost no influence on the strengthening effect. The results enabled the prediction of the creep rupture life of an alloy of a known composition.
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福本 倫久, 原 基, 成田 敏夫2005 年 69 巻 8 号 p. 695-698
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーIn order to improve the cyclic-oxidation resistance of Ni, the coating of a Ni aluminide containing La on the Ni was carried out by the electrodeposition of Al and La in a molten salt. The electrodepositions of Al and La were conducted using a potentiostatic polarization method at 1023 K in an equimolar NaCl-KCl melt containing 3.5 mol%AlF3 and that containing 4 mol%La2O3 and 24 mol%NH4Cl, respectively. Observation and analysis of the cross-section of the specimen after polarization showed that a deposit layer consisting of a thick inner Ni aluminide layer and a thin outer layer containing a large amount of La was formed on the Ni specimen. The cyclic-oxidation resistance of the specimen coated with the deposit layer having the layer containing La as an outer layer was higher than those of the untreated Ni specimen and the specimen coated with deposit layer without La. The scale formed on the specimen coated with the deposit layer without La after the oxidation test was thick and consisted of NiO, whereas the scale formed on the specimen coated with the deposit layer having the layer containing La was extremely thin, and consisted of α-Al2O3.
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中野 敦, 加治屋 直樹, 山田 宏作, 中村 俊一, 松田 豪彦, 末吉 秀一2005 年 69 巻 8 号 p. 699-702
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーPb has been added to bronze to increase its machinability. However, due to the extreme toxicity of Pb that is harmful to the health, the public demand for the use of Pb-free bronze has increased. Therefore, scrap bronze containing Pb cannot be utilized as a recycling material and a large amount of scrap bronze will become industrial waste. So, it is necessary to remove Pb in the scrap bronze to promote recycling.
In the present study, the use of the compound-separation method is attempted for the removal of Pb from bronze containing 5.5 mass%Pb. The result shows that the percentage of Pb removal was effective up to 82% when NaF was added to molten bronze, followed by adding a Ca-Si compound.
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礒本 良則, 三原 壮司, 長谷川 弘2005 年 69 巻 8 号 p. 703-706
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe handling pressure of water-jet has been recently increased in order to achieve a high efficiency of surface treatment of materials. An experimental study of middle-pressure water-jet peening was conducted to investigate the evaluation method for the surface treatment of material and impact conditions of droplets such as size, frequency and velocity. It was found that the damage depth rate was useful for evaluating the degree of damage to material, which was directly identified with the intensity of the surface treatment. The craters caused by the impact of droplets were recognized using aluminum foils mounted on the specimen, and the distributions of droplet diameter and frequency were obtained. The droplet velocity was calculated by the equation of droplet motion. The damage depth rate well related to the kinetic energy of droplets impacted to the target. The impact conditions of water droplets which were needed for new developments of highly efficient water-jet nozzles were thereafter discussed.
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小林 敏治, 原田 広史, 大沢 真人, 佐藤 敦史2005 年 69 巻 8 号 p. 707-710
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe Pebble Bed Modular Reactor (PBMR) is a small atomic power reactor which can be used in areas where the electric power transmission network is not well developed. It generates electricity by gas-turbines that used He-gas as a coolant. Ni-based superalloys are the primary materials used in gas-turbines. However if conventional Ni-base superalloys are to be used for PBMR, turbine maintenances will be difficult due to Co, as it can produce 60Co a recitative material that possesses a long half-life. Therefore, Co-free Ni-base superalloys are required for PBMR.
In this paper, a Co-free single-crystal (SC) superalloy, TMS-82+(-Co), was developed; it was the same chemical composition as the 2nd generation SC superalloy, TMS-82+, except that it is Co-free creep tests were performed on the developed alloy, TMS-82+, under three conditions; 900°C/392 MPa, 1000°C/245 MPa, and 1100°C/137 MPa; CMSX-4, a popular SC alloy, was used as comparison.
TMS-82+(-Co) displayed superior creep-rupture life in all creep tests; however, detrimental TCP were observed in the microstructure of the sample that underwent creep testing at 1100°C/137 MPa. This, the developed Co-free SC alloy should be further modified for long-term microstructural stability. Elimination of phase formation will allow the alloy to be utilized in the PBMR.
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淺香 隆, 菊川 久夫2005 年 69 巻 8 号 p. 711-714
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーTo evaluate the physical properties of a bone, a specimen is often deep-frozen or chemically fixed with reagents such as formaldehyde solution (formalin) or ethanol for antisepsis and sterilization. However, formalin contains formic acid and dissolves bone minerals such as Ca and P into the fixative. To suppress bone mineral solution, we used neutral buffered formalin as the fixative solution. In this study, we investigated the effect of formalin and of neutral buffered formalin fixation on the fracture characteristics of bovine femoral compact bone during relatively long-term preservation. With both formalin and neutral buffered formalin fixation, bone mineral migrates rapidly into the fixative solution. Thus, formic acid is not solely responsible for the dissolution of bone minerals, but some aqueous solutions such as saline can also dissolve bone mineral. With neutral buffered formalin fixation, small calcium phosphate grains precipitate at the surface of blood vessels in the Haversian canal, as observed by scanning electron microscopy. An energy-dispersive spectroscopy also demonstrates the presence of Ca and P. Thus, the precipitated grains are assumed to be hydroxyapatite. In this study we evaluate the effect of formalin preservation, which is to reduce the fracture toughness of bovine femoral compact bone, and to form chemical bridges by the reaction of formaldehyde with the collagen fiber of bone. The collagen fiber was cured and hardened, resulting in a reduction in the fracture toughness of bovine femoral compact bone.
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筑井 則行, 古畑 肇, 山口 典男, 大橋 修2005 年 69 巻 8 号 p. 715-718
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーRecent reports on sintering and bonding using the pulsed electric current bonding process indicate that the metals are subjected to Joule heating due to the electrical resistance at points of contact. However, the influence of bonding conditions on local heating phenomena remains unclear. In this study, to produce clear guidelines on the selection of parameters (bonding pressure, bonding surface roughness, initial current) for pulsed current bonding, joints of SUS304 stainless steel were formed under a variety of conditions.
It was found that the local heating efficiency at the bonded interface becomes larger with high resistance at the contact area when bonding pressure is lower and the bonding surface is smooth. When the initial current is high, local heating at the contact area is accelerated and joint quality is better. However, the initial current has an optimum value. Above this value the current tends to flow at the center of the bonding area, making it difficult to heat the bonding area uniformly.
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中田 大司, 齊藤 敬高, 梅本 歩, 中島 邦彦2005 年 69 巻 8 号 p. 719-722
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーIsothermal growth of β-Si3N4 crystals dispersed in rare-earth (RE=Y, Gd, Nd and La) oxynitride melts (RE-Mg-Si-O-N) was studied during heat treatment at 1773 K under 0.9 MPa of nitrogen pressure for 64 to 512 min. The microstructure of β-Si3N4 crystals was characterized by electron microscopy. It is found that the rate of α-β transformation increases with decreasing ionic radius of the rare-earth element. Likewise, the radii of rare-earth elements make significant differences in the morphology and mean aspect ratio of β-Si3N4. Especially, the aspect ratio of β-Si3N4 crystals with the additive of La2O3 was found to be much larger than that in oxynitride melts with additives of others.
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半谷 禎彦, 北原 総一郎, 天田 重庚2005 年 69 巻 8 号 p. 723-726
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーAlthough die casting enables high productivity, pore defects in the die castings are unavoidable. These pore defects influence the mechanical properties or air leakage efficiency of the products. To reduce the number of pore defects, we performed compression tests on front housings of car air conditioners made by aluminum alloy die casting (ADC12) at room temperature. Because of plastic deformation, the porosity of the die castings becomes lower as the compression strain of the specimen becomes higher, particularly in the middle area of the specimen where the porosity is high. However, the efficiency of the reduction of the porosity and damage of the products differs depending on the condition of compression load. Consequently, it is necessary to investigate the condition of the compression load in order to render this method applicable in practice.
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長岡 亨, 水内 潔, 杉岡 正美, 福角 真男2005 年 69 巻 8 号 p. 727-730
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーJoints composed of stainless steel and Ti were fabricated from Cr-plated SUS304L alloy rods and Ti rods using vanadium foil as an insert metal, in a process using pulsed current hot pressing (PCHP) equipment. The effects of the bonding temperature and the thickness of the Cr-plate layer on the mechanical properties of the joints were investigated. Tensile testing at 300 K and microstructural observations were carried out.
The joints fabricated at 1173 K from 20 μm thick Cr-plated SUS304L rods and Ti rods showed the highest tensile strength of 340 MPa. SEM-EDS analyses revealed that the Cr-plate layer was left after PCHP process and no intermetallic compounds formed at the bonding interfaces. The cracks originally existed in the Cr layer plated on SUS304L rods disappeared perfectly during PCHP process at 1273 K.
In contrast, the joints fabricated from 5 μm thick Cr-plated SUS304L rods and Ti rods showed the lowest tensile strength because of the formation of FeV intermetallic compound in the bonded interlayer.
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新野邊 幸市, 山本 圭司2005 年 69 巻 8 号 p. 731-734
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーA manufacturing process of Fe-Al intermetallic compounds was developed using a lamination cladding method with a pure Fe foil and a commercial Al foil. Fe foil with a size of 20 mm×10 mm×0.05 was wrapped in Al foil 9 times, followed by a heat treatment at temperature ranging from 913 K to 943 K. It was revealed that the reaction between Fe and Al occurred at temperatures more than 933 K, namely the melting point of Al, and a single FeAl2 phase was uniformly formed. The specimens wrapped in Al foil 5 times and 3 times were prepared to obtain the specimens consisting of FeAl and Fe3Al phases, respectively. However, the specimens heated at 933 K were composed of FeAl2 and still retained Fe. The specimens heated at 933 K were subsequently heated at 1273 K. The FeAl and Fe3Al phases were uniformly developed in the specimens wrapped in the Al foil 5 times and 3 times, respectively, revealing that the reheating at 1273 K was effective for the decomposition of the FeAl2 phase.
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伊津野 仁史, 横川 忠晴, 原田 広史2005 年 69 巻 8 号 p. 735-738
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーA new creep constitutive equation for Ni-base superalloys with good reproducibility of high temperature-low stress condition (1100°C/137 MPa) has been proposed. In this paper, an application of the creep constitutive equation for creep curves of lower temperature-high stress condition (900°C/392 MPa) is discussed. Under the condition, it seems evidently that creep curves have no logarithmic elongation at early secondory creep stage, thus a parameter of the creep constitutive equation contained in the logarithmic part decreases to zero. Muti-regression analysis for each parameter of the creep constitutive equation with gamma-prime composition, structural parameters as explanatory variables have been carried out in order to obtain a comparison of the result of multi-regression analysis of high-temperature low-stress condition. Predictions of creep curves at different temperature-stress conditions by interpolation is also discussed.
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池澤 英晃, 広橋 順一郎, 山口 典男, 大橋 修2005 年 69 巻 8 号 p. 739-742
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーIt is difficult to achieve good quality diffusion bonded joints in Al alloys due to the stability of the oxide film on the surface of these alloys. Mg is the most effective element for reducing surface oxide films at the bonded interface of Al and its alloys. It has been demonstrated that Mg additions are effective in breaking down the oxide layer at the bonded interface by a reduction reaction that takes place during the diffusion bonding process under a high vacuum. In order to clarify the effect of environmental pressure (3×10-3 Pa, 3 Pa, 105 Pa) on the reduction reaction at the bonded interface, 3003 Al alloys containing varying amounts of Mg (0, 0.3, 0.6, 1.2, 2.5, 5 mass%) were diffusion bonded.
The mechanical properties of the joints were improved by the reduction reaction of Mg. The optimum Mg level for improving the joints was determined to be 0.3-1.2% and 0.3-0.6% at environmental pressures of 3×10-3 Pa and 3 Pa, respectively. 3003 Al alloys with Mg added in the range of 0.3-0.6% were well bonded regardless of the vacuum pressure.
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小泉 裕, 原田 広史, 小林 敏治, 横川 忠晴2005 年 69 巻 8 号 p. 743-746
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーLong component-life of at least two years under a daily start and stop condition is required on turbine blades and vanes in land-based power plants. For this reason, a creep rupture life of 10000 hours or longer is required for the application of Ni-base superalloys. In this paper, long-term creep property of more than 15000 hours was analyzed for a second-generation Ni-base superalloy, TMS-82+. Consequently, Larson-Miller parameters in the range of C=12-14 resulted in good fits over the short-to-long-term creep rupture life, even though C=20 is conventionally used for Ni-base superalloys. In addition, the creep strength of TMS-82+ exceeds that of CMSX-4 under wide range of stress/temperature conditions, especially under the higher temperature and lower stress condition.
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増田 進吾, 松村 義人, 西 義武2005 年 69 巻 8 号 p. 747-750
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーSmFe2.4 alloy thin films were prepared by DC magnetron sputtering process at different substrate temperatures from 323 K to 623 K and at different Ar gas pressure from 0.5 to 1.0 Pa. The magnetostriction increased with decreasing of an Ar gas pressure as sputtering gas. On the other hand, the large magnetostriction was observed at high Ar gas pressure on heating at 623 K of high substrate temperature. The maximum value of magnetostriction over 1400 ppm at 1.2 MA/m was found in a Sm-Fe film prepared at 423 K of substrate temperature and at 0.5 Pa of argon gas pressure. This value was top data for the compressive (negative) magnetostrictive films up to now. From this result, it was concluded that the amount of a magnetostriction was strongly affected by change in the morphology of the thin film.
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沼崎 謙一, 内田 晴久, 西 義武2005 年 69 巻 8 号 p. 751-754
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーMultilayer structural mover device was prepared, which was composed of 1 μm thick LaNi5 film deposited on Cu thin sheet substrate. To enhance the responsiveness, the Pd thin film of the thickness of about 10 nm was deposited. Significantly large displacement and reversibility were observed by change in hydrogen pressure.
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小笠原 崇, 内田 晴久, 西 義武2005 年 69 巻 8 号 p. 755-758
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーA mechanical device with hydrogen storage thin film alloy was made up and tested. The sample in thin film form deposited on polyimide film substrate was driven by the mechanical volume change in the course of hydrogen sorption reactions. In this study, the correlations of mechanical strain, applied electric current in the sample and surface temperature were investigated. Not only the hydrogen pressure around but also the electric current in the film applied, where the electric resistance changed with the hydrogen amount absorbed, controlled the sample movement.
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高橋 辰也, 森下 忠衛, 西 義武2005 年 69 巻 8 号 p. 759-762
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーInfluences of electron beam irradiation on stress-strain curves of tensile test were studied for polycarbonate resin. The electron beam (EB) irradiation enhanced the tensile strength and ductility. The maximum values were found at 0.2 MGy of EB-irradiation. On the other hand, excess EB irradiation decreased the tensile fracture stress and ductility. To discuss the effect of electron beam on tensile strength and ductility, the dangling bonds formation was evaluated by ESR signals. The enhancements of ductility and fracture stress can be explained by stress relaxation induced by increase in density of dangling bonds.
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村雲 岳郎, 小林 敏治, 原田 広史2005 年 69 巻 8 号 p. 763-768
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe creep behavior of Ni-base single-crystal superalloys TMS-75 and TMS-26 with various γ′ fractions was investigated at 800°C and 735 MPa. Creep strength of two-phase alloys was superior to single phase alloys. The creep rupture lives were the longest for the 60%γ′ alloys. In contrast with creep behavior above 900°C, 40%γ′ alloys were stronger than 80%γ′ alloys at 800°C. 60%γ′ alloy of TMS-26 was much stronger than that of TMS-75 because of lower Co and Re contents and lower stacking fault energy. Changes in the microstructure after creep rupture were studied. While raft structure was observed perpendicular in 60%γ′ alloy of TMS-26, rafts were parallel in 80%γ′ alloy. Super stacking faults were often observed in γ′ precipitates in 60%γ′ alloy of TMS-75. However, super stacking faults were not frequent in the other alloys. Usual a/2 <110> dislocations were observed in γ matrix in 20 and 40%γ′ alloys, and superdislocations were observed in coarse γ′ phases in 80%γ′ alloy.
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熊谷 達夫2005 年 69 巻 8 号 p. 769-774
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーMechanically alloyed amorphous ceramic powders with a chemical composition of (ZrO2-3 mol%Y2O3)-26.2 mol%SiO2-3.4 mol%CeO2 have been prepared by a planetary ball mill. Thermal differential analysis (DTA) experiments show that the onset temperature of crystallization increases from 1071 to 1105 K as the heating rate increases from 5 to 50 K/min. These amorphous powders have been consolidated at the heating rate of 480 K/min under the applied stress of 150 MPa in a chamber evacuated to 10 Pa, using an electrical discharge consolidation system. After the formation of tetragonal zirconia solid solution, marked increase in the relative density occurs in the narrow temperature range from 1178 to 1315 K. The fully dense bulk sample sintered at 1315 K consists of tetragonal (or tetragonal+cubic) zirconia solid solution together with amorphous silica. The average crystallite size increases from 10 to 15 nm as the consolidation temperature increases from 1223 to 1315 K. Moreover, the isothermal consolidation treatment for about 700 s causes further increase in the crystallite size by a factor of two, regardless of the consolidation temperature. These results indicate that the crystallite size can be widely changed (10~30 nm) by controlling the consolidation temperature and the isothermal consolidation period of time.
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細野 博志, 茶園 和博, 桑原 秀行, 市井 一男, 大石 敏雄2005 年 69 巻 8 号 p. 775-779
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーFe-5, 10, and 14 mass%Cr alloy foils with the thickness of 60 μm or less were plasma nitrided at 873 K and nitrogen was saturated throughout the foil specimen.
Microstructure on the cross section of the nitrided specimen was consisted of an external nitrided layer of γ′-Fe4N and an internal nitrided layer of dispersed precipitates of CrN in the α-Fe matrix.
Dissolved chromium was found to retain 1.23, 3.74, and 6.02 mass% by XPS (X-ray Photoelectron Spectroscopy) for the alloy specimens of Fe-5, 10, and 14 mass%Cr nitrided at 873 K for 180 ks, respectively. The results of XPS and the chemical analysis of total nitrogen lead to the conclusion that the concentrations of dissolved nitrogen were 0.41, 0.91, and 1.63 mass% in plasma-nitrided Fe-5, 10, and 14 mass%Cr alloy specimens, respectively. The dissolved nitrogen concentrations were significantly higher than those attained by gas nitriding.
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中野 博昭, 桑原 裕樹, 大上 悟, 小林 繁夫, 福島 久哲, 尹 正模2005 年 69 巻 8 号 p. 780-786
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーPoly(2-vinylpyridine) films were deposited on Zn substrate by electropolymerization using galvanostatic technique at 30°C in pH 5 aqueous solution containing methanol. Films were also formed by employing cyclic voltammetry and potentiostatic techniques; these were compared with those formed using galvanostatic electrolysis. The thickness of films formed by galvanostatic electrolysis increased in proportion to the amount of charge passed during electropolymerization but decreased with increasing current density because of increased hydrogen evolution. The FT-IR spectra and the color of the films suggested that the structure of poly(2-vinylpyridine) films changed from the non-branched to the branched chain type with the higher current densities. The anodic current density for Zn dissolution in 3%NaCl solution was significantly decreased by coating with poly(2-vinylpyridine) films. After electropolymerization at 50 A•m-2, the anodic reaction was most inhibited, showing excellent corrosion resistance. Although the electrochemical techniques employed for the film preparation had no influence on the thickness or the structure of films, the films formed by galvanostatic electrolysis contained the fewest cracks and gave the best corrosion resistance.
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真野 毅, 渋谷 佳男, 杉山 治, 中山 洋, 高井 治2005 年 69 巻 8 号 p. 787-792
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーA double-layers film, in which the top layer was a diamond-like carbon (DLC) film and the bottom layer was a compositionally graded film of silicon and carbon compounds with decreasing C/Si atomic ratio to a substrate, was successfully formed on a Ti-6Al-4V substrate by an ionization deposition method. In the film deposition process, a benzene vapor was used for the DLC deposition, and hexamethyldisiloxane and benzene vapors were used for the compositionally graded film of silicon and carbon compounds, as source gasses. The results of ball-on-disk and scratching tests showed that the double-layers film with graded composition provided a low friction coefficient, high wear resistance and good adhesion with the Ti-6Al-4V substrate compared to a single-layer DLC film. The DLC-based double-layers film developed in this study is very effective in extending the applications of the Ti-6Al-4V alloy for antifriction components.
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吉田 和弘, 三科 博司, 佐々木 信也, 森田 真史, 馬渕 清資2005 年 69 巻 8 号 p. 793-800
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe authors developed 3Y-PSZ/AISI 316L composites for the bearings of joint prostheses, which were then evaluated in terms of their mechanical properties, such as density, hardness, bending strength, fracture toughness and wear resistance, as well as corrosion resistance. The composites (AISI 316L contents were 0, 10, 20 and 30 vol%) were fabricated by spark plasma sintering. The composites consist of tetragonal zirconia and austenite stainless steel. The Vickers hardness and bi-axial bending strength of the composite decrease from 14.3 GPa to 8.93 GPa and 1585 MPa to 617 MPa, respectively, when the AISI 316L content is increased from 0 vol% to 30 vol%. Fracture toughness of the composite increased from 4.99 MPa•m1/2 to 6.03 MPa•m1/2. The composites showed improved wear resistance (3Y-PSZ; 3.08×10-10 mm2/N, 10 vol% composite; 2.11×10-10 mm2/N, 20 vol% composite; 0.28×10-10 mm2/N, 30 vol% composite; 0.00×10-10 mm2/N). The wear resistance of the 30 vol% composite was higher than conventional biometal and bioceramic (AISI 316L; 35.4×10-10 mm2/N, Co-28Cr-6Mo; 11.0×10-10 mm2/N, Al2O3; 0.30×10-10 mm2/N). The composites showed more than 3 times greater corrosion resistance than the monolithic AISI 316L in PBS(−) at 37°C. In particular, nickel ion release was lower than for AISI 316L. The corrosion resistance of 30 vol% composite during the wear test was more than 37 times higher than for AISI 316L. The 30 vol% composite was successfully toughened and showed higher resistance to wear and corrosion when used as bearing material for joint prostheses.
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小口 かなえ, 鈴木 俊夫2005 年 69 巻 8 号 p. 801-803
発行日: 2005年
公開日: 2005/10/12
ジャーナル フリーThe Computational efficiency of a conventional phase-field simulation was compared with a modified simulation in which the thermal field away from the interface was calculated by a random-walk algorithm. The growth velocity and computational time were compared for the simulations by two programs. The error and computational time were mainly dependent on the distance from the interface, at which the random-walk calculation was started. The distance was given by the number of calculation mesh intervals between the interface and the edge of the random-walk calculation area, and the error in growth velocity decreased but the computational time increased with increasing the number of mesh intervals. When the number of mesh intervals was set to be 80, the error in growth velocity was negligible and the computational time was reduced by 20%. The computational efficiency was sigficantly improved at small undercooling conditions, where the necessary calculation area for thermal diffusion became large.
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