著者

世利 修美 丹野 聡司

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.73, no.11, pp.878-883, 2009 (Released:2009-11-01)

参考文献数

9

被引用文献数

7 7

---

Behavior of dry corrosion which is electrochemical reaction between Al-Mg-Si alloy 6063 and ethanol in gasoline has been investigated. Dry corrosion has not been observed in E3 (3% ethanol) and E10 (10% ethanol) at room temperature, but observed in E3 and E10 when a small amount of aluminum chloride had been added to them at room temperature. The higher solution temperature is, the more often the dry corrosion occurs. Dry corrosion has also been observed in the above solution environments in which 0.1% and 1% water contained. Occurrence of dry corrosion was detected by the area polarization method, which revealed that initiation and propagation of the dry corrosion corresponds to the decrease of anodic polarized resistance of 6063.

著者

本間 敏夫

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.21, no.4, pp.263-267, 1957 (Released:2008-04-04)

参考文献数

11

被引用文献数

6 9

---

The characteristics of Umklapp transformation in Fe-Ni alloy containing 31%Ni were clarified through various experiments. (1) The Umklapp process is characterized by a burst phenomenon. (2) Great kinetic energy accompanied by the umklapp process can make a martensite leaf propagate into a temperature range higher than the usual γ→α transformation temperature in a single crystal with temperature gradient. (3) The 1st burst temperature is scattered statistically in a wide range of temperature. (4) The transformation amounts produced by the 1st burst increases with the degree of supercooling.

著者

宮川 長二 羽田 紘一 後藤 公美 宮原 鉄洲

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.53, no.11, pp.1168-1176, 1989 (Released:2008-04-04)

参考文献数

26

被引用文献数

2 1

---

Small particles of Fe3C (cementite) in an acicular shape (0.2 μm in length, 10/1 in axial ratio) have been synthesized by heating acicular shaped powders of iron (α-Fe) in a flow of carbon monoxide or/and hydrogen gas mixture. X-ray analyses, electron microscopy, magnetic measurements and Mössbauer spectroscopy are employed for the characterizations. The chemical treatment required to obtain single phase Fe3C particles has been studied in the carburizing temperature range from 623 to 873 K. The saturation magnetization (σs) and intrinsic coercive force (iHc) attained are around 138×10−6 Wb·m·kg−1 (110 emu·g−1) and 51.7 kA·m−1 (650 Oe), respectively. Possible applications for magnetic recording powders are found for Fe3C particles synthesized at 823 K and above through a durability test of magnetic properties, by placing the particles in air of 333 K-90% relative humidity for a prolonged time.

著者

藤田 浩示 高原 良博

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.71, no.11, pp.1057-1060, 2007 (Released:2007-11-02)

参考文献数

9

---

We have studied the effect of the chlorine addition on the ultraviolet transmission property of soda-lime glasses to develop the ultraviolet penetration glass with soda-lime compositions. At first, a molecular-dynamics calculation is carried out to investigate how the addition of chlorine has influence on the non-bridged oxygen which causes the absorption of ultraviolet in the soda-lime glass. It is shown from the calculation that the chlorine addition reduces the amount of the non-bridged oxygen. Based on the result, we fabricate the soda-lime glasses containing chlorine by using a platinum crucible, and then measure the transmittance of ultraviolet at 260 nm wavelength. Apparent improvement of ultraviolet transmittance of the soda-lime glasses is confirmed from the measurements. As a result, improvement of ultraviolet transmittance is below 10%, so enough improvement of ultraviolet transmittance is not available by addition of chlorine.

著者

高林 弘実 北田 正弘 辻本 勝浩

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.69, no.7, pp.538-543, 2005 (Released:2005-10-12)

参考文献数

17

被引用文献数

3 3

---

The discoloration and chemical composition changes of red-lead used for wood-block print made in the late Edo period have been investigated. Both the chromaticity and lightness of red-lead decrease with discoloration, and its hue exhibits very little change. This is due to the reflectance decrease of red-lead in a long-wavelength range beyond the absorption edge of 580 nm. Red-lead is a mixture of Pb3O4 and β-PbO and has a grain size of 0.05-0.2 μm. The X-ray diffraction intensity of β-PbO considerably decreases with discoloration in comparison with that from Pb3O4. This result shows that β-PbO is more reactive than Pb3O4 in the mixture. The results of XPS measurement suggest that both lead chloride and lead carbonate exist in the surface layer of red-lead.

著者

蒲地 一嘉

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.46, no.4, pp.401-406, 1982 (Released:2008-04-04)

参考文献数

5

被引用文献数

1

---

Since austenitic stainless steels have some useful properties for medical instruments, such as high corrosion resistance, high strength and high elasticity, they are used as needles for acupancture and anesthesia. The failure of the needles, however, have been reported to occur during medical treatments. This becomes a serious problem for both a doctor and a patient.Causes of the failure have been studied in the present paper and the following conclusion has been derived; In case in which the needle is used as an anode, the failure occurs due to pitting corrosion, whereas, in case in which it is used as a cathode, embrittlement due to hydride formation occurs.

著者

井野 博満 上澤 千尋 伊東 良徳

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.72, no.4, pp.261-267, 2008 (Released:2008-04-01)

参考文献数

12

被引用文献数

1 1

---

Surveillance data for pressure vessel steels of the 51 LWR plants in Japan were analyzed to make clear the effect of neutron irradiation on the brittle transition temperature of the steels. The clear difference observed in the rise of the ductile to brittle transition temperature between the normal and accelerated irradiation samples is considered to be due to the effect of neutron flux. The present analysis is discussed in comparison with the result of computer simulation based on the rate equations of the radiation damage process and the recent experiments of APFIM and positron annihilation.

著者

佐々木 靖男 天野 宗幸

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.35, no.1, pp.77-81, 1971 (Released:2008-04-04)

参考文献数

9

---

The alloys containing 3.8 at%, 7.2 at% and 14.5 at% hydrogen were prepared and were comminuted with a ball mill. The particle size distribution of the powders was measured by screen analyses, and microscopic observation of the particle shape was carried out.The main results obtained are as follows:(1) The alloys are brittle enough to be comminuted readily.(2) Cracking and fragmentation of the alloys are enhanced by thermal cycling in the hydrogenation process.(3) With increasing the hydrogen content in the alloys, a higher percentage of fine particles is obtained.(4) Particle shape varies with the hydrogen content of the alloys. Rounded or irregular particles are obtained from the lower concentration alloys and acicular or angular particles from the higher concentration alloy.

著者

小原 嗣朗 武藤 範雄

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.45, no.4, pp.411-416, 1981 (Released:2008-04-04)

参考文献数

17

被引用文献数

12 9

---

The compatibility of SiC fibers with aluminum was investigated. The SiC fibers made from an organosilicon polymer was used in the present study. The fiber specimens were aluminum-coated by vacuum evaporation and heat treated at temperatures 673 to 873 K for 90 ks, or 973 to 1373 K for 1.8 ks in an argon atmosphere. Then, the fiber specimens were tensile tested at room temperature.For the solid state aluminum, the SiC fibers showed no loss in tensile strength after the heat treatments at 673 to 773 K, but showed a slight degradation in tensile strength after the heat treatment at 873 K. For the liquid state aluminum, the SiC fibers showed a noticeable degradation in tensile strength after the heat treatments at temperatures higher than 973 K. However, the degradation in tensile strength was decreased in the solid and the liquid state by alloying Si with aluminum.

著者

西田 恵三 室橋 春光 山本 強

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.41, no.11, pp.1101-1106, 1977 (Released:2008-04-04)

参考文献数

19

被引用文献数

2 6

---

Iron test pieces were diffusion-annealed in an evacuated silica capsule containing the powdered (100∼200 mesh) 50 wt%Sb-Fe alloy consisting of α and ε phases as an Sb vapor source for 9∼440 hr at 700∼950°C. The test pieces were then analysed with an EPMA and the penetration curves of them were obtained.Each penetration curve was analysed by means of the Matano-Boltzmann method to obtain the chemical diffusion coefficients (\ ildeD). From these values the activation energies for diffusion (\ ildeQ) were calculated.Surface concentration of the test pieces (αmax) at each annealing temperature coincided approximately with the solubility observed in the phase diagram of an Fe-Sb system at lower temperatures, while a significant deviation was found in solubility at higher temperatures. Fine alumina makers placed on the test pieces prior to diffusion were found always on the surfaces after annealing so that it is considered that Sb atoms diffuse predominantly in the α-phase of this system. Each penetration curve was similar to an error function curve and \ ildeD at each temperature showed a relatively small dependence upon Sb concentration. There was a gap in the Arrhenius plot owing to magnetic transformation. The activation energies for diffusion (\ ildeQ) obtained from the data at higher temperatures varied from 59.5 kcal/mol for 1 at%Sb to 52.5 kcal/mol for 4 at%Sb and that for impurity diffusion of Sb in iron (QSb*) was evaluated to be about 63 kcal/mol.

著者

藤垣 裕子

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.66, no.12, pp.1246-1252, 2002 (Released:2008-04-24)

参考文献数

13

---

To establish the risk-based material engineering, survey of basic concepts on social risk is inevitable. The present study first surveyed the concept of “social risk” based on the basic literatures in the area of STS (Science and Technology Studies). Social rationality is considered as the concept to legitimate the decision making for public problems that even scientists and engineers cannot provide the right answers. Consensus conference, Focus goups, and Science shops are introduced as social devices to construct social rationality for selecting/evaluating the engineering for future society. These concepts and devices are important for construct the future of risk-based material engineering.

著者

美馬 源次 倉貫 好雄

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.22, no.2, pp.95-99, 1958 (Released:2008-04-04)

参考文献数

8

被引用文献数

2 1

---

The surface tension of fluxes and the interface tension between molten Sn and fluxes were measured by the maximum bubble method and the drop weight method, respectively, in the temperature range of 300∼500°. The fluxes used were ZnCl2, SnCl2 and mixtures of ZnCl2 and NH4Cl NaCl, KCl or SnCl2. The results obtained are summarized as follows: (1) The surface tension of SnCl decreased while the surface tension of ZnCl2 increased with rising temperature. (2) The surface tension of mixed fluxes increased as the quantity of the 2nd or the 3rd element added to ZnCl2 increased. (3) The interface tension between Sn and ZnCl2 is expressed by the following equation: σ=730.4−0.564θ; where σ: interface tension, dynes/cm, θ: temperature, °C; (4) In the case of Sn and 2 component fluxes, it may be said that the addition of NH4Cl to ZnCl2 results in a larger decrease of the interface tension than the addition of NaCl, but the addition of SnCl2 shows no effect and the addition of KCl shows a small increase of the interface tension. (5) In the case of Sn and 3 component fluxes, by the addition of the 3rd elements (NaCl, SnCl2) to ZnCl2-NH4Cl, the decreasing effect of the interface tension by the 2nd element (NH4Cl) was lost.

著者

須藤 一 山名 紳一郎 山口 紀之

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.41, no.11, pp.1172-1179, 1977

---

Static and Impact tension tests have been carried out in order to investigate the effects of the aging condition and the deformation speed on the elongation per cent and reduction of area of Al-4.0%Cu and Al-12.6%Ag alloys which aged in the various stages.<BR>The results obtained are as follows:<BR>(1)&emsp;With increasing impact velocity, the ductility generally increases in a well-known manner and the dimples formed on the fracture surface is enlarged in mean size.<BR>(2)&emsp;As-quenched specimens and those in the incipient stages of aging have a small amount of precipitates which are the source of void formation. Accordingly, the ductility of these alloys was often decreased by impact tension owing to slipping-off fracture or grain boundary brittle fracture.<BR>(3)&emsp;Grain boundary ductile fracture takes place in the static tension of fully aged or over-aged alloys by linking voids formed around grain boundary precipitates. In the impact tension, however, transgranular fracture occurs with the resulting excellent reduction in area.

著者

小野寺 龍太 祝 桂合 森田 泉

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.66, no.5, pp.521-527, 2002 (Released:2008-04-24)

参考文献数

24

---

We examined the effect of grain size on flow stress and yield-point phenomena in variously heat-treated low-carbon steel specimens. We found that the experimental results are easily understood if the flow stress consists of two internal stresses, Yint and Yir. Yint is a common internal stress that is work hardened; Yir is the cause of yield-point phenomena, and its value is supposed to be rapidly decreased (work-softened) to zero with strain. Both Yint and Yir were affected by grain size. Furthermore, the effect of heat treatment was strong on Yint but weak on Yir. The Hall-Petch coefficient k was appreciably larger at lower yield points than in the large strain region. This comparison supports the hypothesis of the existence of two internal stresses because the grain size dependence of flow stress at lower yield points has two origins, Yint and Yir, whereas the latter case has only one origin, Yint. In the strain region exceeding yield-point elongation, the stress-strain curves of specimens with various grain sizes were perfectly superposed on each other by parallel translation, which means that if Yint is expressed as Yint(ε)=f(ε) for a specimen with a certain grain size, it is expressed as Yint(ε)=f(ε+Δε)−Δσ for arbitrary grain size specimens, where Δε and Δσ are the amounts of translation in strain and stress, respectively.

著者

城戸 竜太 桑野 亮一 日野 実 村山 敬祐 黒坂 成吾 小田 幸典 堀川 敬太郎 金谷 輝人

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.84, no.3, pp.74-79, 2020-03-01 (Released:2020-02-25)

参考文献数

11

被引用文献数

1 1

---

In this study, the effect of anodization and electroless Ni-P plating on the fatigue strength of commercial A5052-H14 and A2017-T4 aluminum alloys was investigated. The coated aluminum alloys were tested using a rotary bending fatigue testing machine. Anodization led to a slight increase in the fatigue strength of the A2017-T4 alloy of approximately 10% because of the suppression of the generation of fatigue crack, and anodization with a 5-µm thickness for A5052-H14 also led to a slight increase in the fatigue strength. However, anodization with a 20-µm thickness for A5052-H14 led to reduced fatigue strength because of the pits that formed in the film. In addition, electroless Ni-P plating drastically improved the fatigue strength of the A5052-H14 alloy by suppressing the generation of fatigue crack.It also improved the fatigue strength of the A2017-T4 alloy in the high-stress region. However, the fatigue strength in the low-stress region was the same as that of the non-coated specimens.This fatigue strength should have originated from the hydrogen embrittlement by the hydrogen introduced into the specimen during the plating.

著者

吉弘 辰明 土山 聡宏 高木 節雄

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.67, no.7, pp.362-367, 2003 (Released:2008-04-24)

参考文献数

7

被引用文献数

2 2

---

Chemical reaction process(Ti+CrB→Cr+TiB) of isolated CrB particle in a Ti powder compact was investigated to find a proper sintering condition for producing TiB/Ti composites by reaction sintering. EPMA analysis revealed that the formation of TiB starts at 1223 K during heated with the rate of 0.17 K/s. The reaction proceeds topochemically with the movement of a reaction band from the particle surface to inside. The unreacted-core model was applied to the reaction of a CrB particle for the analyse the reaction rate of CrB particle. It was found that diffusion of Ti and Cr atoms in a TiB layer controls the whole reaction rate, and then the time of reaction finish at 1223 K was estimated as a function of initial CrB particle radius.

著者

太田 和一

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.20, no.8, pp.417-421, 1956 (Released:2008-04-04)

参考文献数

1

---

The distribution of hardness in transverse and oblique sections of a cold rolled Armco iron and nickel was measured. The distribution curves showed a convex form up to some degrees of working. The effect of skin pass upon the distribution of hardners and the relationship between the distribution of hardness and residual stress were also studied.

著者

明日香 壽川 山本 政一郎 朝山 慎一郎

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.74, no.1, pp.61-63, 2010

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&nbsp;&nbsp;Endo <i>et al</i>. says that the sea level will be lower due to the ice in the polar region, and refers to the IPCC (Inter-governmental Panel on Climate Change) assessment reports as if these reports would have supported the notion. The referred sections of IPCC reports, however, describe the effects of &ldquo;polar ice sheets&rdquo; of Antarctica and Greenland combined, and not &ldquo;ice in the polar region&rdquo; as Endo <i>et al</i>. says. The misinterpretations of these terms also lead to their unfounded and untenable criticism on the &ldquo;White Paper on the Environment&rdquo; published by the Ministry of the Environment, Japan.<br>

著者

遠藤 小太郎 吉田 真悟 中嶋 貴裕 行本 正雄 武田 邦彦

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.70, no.5, pp.420-426, 2006

被引用文献数

1

---

&nbsp;&nbsp;The respective awareness of the Intergovernmental Panel on Climate Change (IPCC), the Japanese government, media and citizens about the change of sea level at some future date due to climate change was surveyed and analyzed. Three official reports from the IPCC, the white paper on the Quality of the Environment in Japan from the government, the articles in the Asahi Shimbun newspaper from about the past 20 years, and the questionnaires by the Japanese and local governments conducted towards citizens were used. The results of this investigation were that the IPCC concluded in their past three reports that the sea level was estimated to be lower because of ice in the polar regions due to climate change, the Japanese government did not describe this point clearly, the newspaper drew the opposite conclusion from the IPCC and the understanding of citizens was that the change in climate caused the sea level to rise. These differences were due to the lack of or misunderstanding of scientific knowledge such as Archimedes's Principle and the migration of fluid materials, and to the psychological trend of human beings. It is necessary for the government and media to clearly explain and announce these scientific facts in a modern society which maintains a close relationship to science.<br>

著者

田中 眞奈子 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.74, no.4, pp.250-257, 2010 (Released:2010-04-01)

参考文献数

16

被引用文献数

7 5

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The composition and microstructure of nonmetallic inclusions of a Japanese matchlock gun, called Hinawa-ju in Japanese, fabricated in the Edo period have been investigated. The purpose of this work is to study the composition and microstructure of nonmetallic inclusions of the barrel and to obtain modern materials-science data of the raw materials of the Japanese matchlock gun. Test pieces are cut from the center and the male screw of the barrel. Nonmetallic inclusions of the barrel are observed using an optical microscope and scanning electron microscope (SEM). The small-area concentration of a nonmetallic inclusion is obtained by electron dispersive X-ray analysis (EDS). The electron backscattering pattern (EBSP) is analyzed using an ultrahigh-resolution scanning electron microscope. Fe, Si, Al, Ca, K, Mg, P, Na and Ti are detected from nonmetallic inclusions of the center of the barrel. As Ti is detected from many parts of the nonmetallic inclusions, iron sand is inferred to have been used as the raw iron material of the barrel. Nonmetallic inclusions of the center of the barrel are classified into two groups. One is a plural phase and is consisted of FeO (wustite), Fe-Si-O grains, multi-element grains and glass-rich matrix oxide. The other type is a single phase of aluminum silicate glass. Fe, Si, Al, Ti, Ca, Mg, K, Na, P, Mn and S are detected from nonmetallic inclusions of the male screw of the barrel. As Ti is detected from many parts of the nonmetallic inclusions, iron sand is again thought to have been used as the raw iron material of the male screw. Nonmetallic inclusions of the male screw are of the plural phase and consist of Fe-Ti-O grains, aluminum silicate oxide and aluminum silicate glass matrix.