巻号一覧
75 巻, 8 号
選択された号の論文の8件中1～8を表示しています
- |<
- <
- 1
- >
- >|
論文
-
小林 伸聖, 鶴井 隆雄, 大沼 繁弘, 増本 健2011 年 75 巻 8 号 p. 419-423
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーWe have investigated the structure of (Fe, Co)-Mg-F nano-granular TMR films by HRTEM. These films have nano-granular structure which consists of Co or Fe nano-granules with diameter of 2-3 nm surrounded by thin intergranules of MgF2 with crystal structure. The structure of Co granules is crystalline, whereas the one of Fe is an amorphous state, which may be attributed to small MR ratio of 42 vol%Fe-(Mg0.32F0.68) film compared with the theoretical one calculated from spin polarization (P) of Fe crystal.
抄録全体を表示PDF形式でダウンロード (3561K) -
川森 重弘, 黒田 潔, 春日 幸生, 横内 正洋, 藤原 弘, 飴山 惠2011 年 75 巻 8 号 p. 424-431
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーTo enhance the mechanical properties of magnesium (Mg) alloys, powders of pure Mg (Al2O3/Mg) dispersed with over 10 vol% alumina (Al2O3) particles were made by ball milling powder mixtures of pure Mg and Al2O3 particles with particle sizes of 0.3 and 1 μm.
The effect of the Al2O3 content of hot-pressed discs formed from the Al2O3/Mg powders on the mechanical properties of the discs was investigated. The Al2O3 particles were found to be uniformly dispersed in the Al2O3/Mg discs. The hardness of the discs increased sharply at an Al2O3 content of 20 vol%. This is considered to be because of the excellent interfacial bonding between Mg and Al2O3 when the Al2O3/Mg discs contain a sufficient amount of Al2O3 particles and have a sufficient interparticle distance. The maximum hardness of a 20 vol% Al2O3/Mg disc (with an Al2O3 particle size of 0.3 μm) was 220 HV, which is much higher than the hardness of AZ91 Mg alloys. The bending strength of the Al2O3/Mg discs increased from 0 to 10 vol% Al2O3 and then decreased from 20 vol% Al2O3. It is considered that the 0 and 10 vol% discs have similar fracture deflections and that the 10 vol% discs with Al2O3 particles can withstand higher compression and tension forces than the 0 vol% discs which do not contain any particles. The reason for the lower bending strength of the 20 vol% Al2O3 disc is thought to be because it is harder and more brittle, making it easier for voids to form in the discs, and thus making it easier for cracks to propagate on the specimen surface.
抄録全体を表示PDF形式でダウンロード (4401K) -
寺門 修, 佐伯 高史, 入里 亮二, 平澤 政廣2011 年 75 巻 8 号 p. 432-437
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーIn the present paper we address the novel chlorination process for recovery of indium selectively from dental metal recycling sludge which contains considerably high amount of indium. The process is based on the utilization of ammonium chloride, NH4Cl, as chlorination reagent. It was found that indium could be successfully recovered from the sludge in the form of volatile indium chloride by heating the mixture of sludge and NH4Cl at the temperature of 400°C under inert atmosphere. The influence of process parameters, such as composition of NH4Cl, was investigated in order to achieve high process efficiency.
抄録全体を表示PDF形式でダウンロード (6160K) -
崔 禎恩, 北田 正弘2011 年 75 巻 8 号 p. 438-444
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーThe microstructure of the surface corrosion layer of the bronze coin Headongtongbo fabricated in the Koryo period (11th-12th centuries) in Korea has been investigated. The coin was first produced in 1097 and had been circulated in the first Koryo dynasty. Optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to determine the structure of the specimen. The matrix composition of the specimen is Cu-6.1 mass%Sn-1.4 mass%Pb-0.5 mass%S. Metallic phase αCu, Pb and Cu2S are observed in the bronze matrix. The surface corrosion layer consists of brown, grayish brown and greenish corrosion matters. The closer to the surface, the Cu concentration decreases. Conversely, the closer to the surface, Pb and Sn concentrations increase. The brownish layer consists of CuO. A mixture of Cu2O, CuO and SnO2 is observed from the grayish brown layer on the αCu matrix. The greenish corrosion layer is malachite (Cu2(CO3)2(OH)2) containing Sn and Pb. Chlorine introduced from the environment is detected from a part of the corrosion layer.
抄録全体を表示PDF形式でダウンロード (5173K) -
赤堀 俊和, 新家 光雄, 仲井 正昭, 堤 晴美, 近藤 祐介, 服部 友一, 福井 壽男2011 年 75 巻 8 号 p. 445-451
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーThe microstructures, mechanical properties, and biocompatibilities of as-solutionized Zr-Nb system alloys with different Nb contents for biomedical applications were investigated. The microstructures of Zr-5 mass%Nb, Zr-10 mass%Nb, and Zr-20 mass%Nb alloys subjected to solution treatment (ST) consist of α′, ω, and β phases while the microstructure of Zr-30 mass%Nb alloy subjected to ST consists of almost all single β phase. Young's modulus of Zr-20 mass%Nb alloy shows the lowest value of 63 GPa among the others alloys although the tensile strength and 0.2% proof stress decrease because of decrease in volume fraction of ω phase while Zr-10 mass%Nb alloy with a large amount of ω phase shows the highest values of Young's modulus, tensile strength, and 0.2% proof stress. The elongations of Zr-20 mass%Nb and Zr-30 mass%Nb alloys show relatively high values of 22% and 24%, respectively. The cell viability and bone-bonding characteristics of Zr-Nb system alloys are improved with increasing Nb content. Therefore, it is considered that Zr-Nb alloys have relatively high biocompatibility and belong to bio-inert metallic biomaterial.
抄録全体を表示PDF形式でダウンロード (3837K) -
赤堀 俊和, 新家 光雄, 仲井 正昭, 堤 晴美, 近藤 祐介, 服部 友一, 福井 壽男2011 年 75 巻 8 号 p. 452-459
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーThe frictional wear characteristics, mechanical properties, and biocompatibilities of biomedical Zr-20 mass%Nb alloy (Zr-20Nb) subjected to solution treatment (ST) and air-oxidizing process (AOP) were investigated. Vickers hardness of the specimen surface of Zr-20Nb subjected to AOP at 973 K, 1073 K, and 1123 K are approximately 4.5 times larger than that of Zr-20Nb subjected to ST. Young's modulus of Zr-20Nb subjected to AOP increases with increasing AOP temperature up to 1073 K. 0.2% proof stress, tensile strength, and elongation of Zr-20Nb subjected to each AOP decrease proportionally with increasing AOP temperature, and is inferior to those of Zr-20Nb subjected to ST because of the growth of oxide layer with a large amount of micro-cracks and the diffusion of oxygen into the subsurface. Frictional wear loss of Zr-20Nb subjected to each AOP decreases drastically as compared to that of Zr-20Nb subjected to ST. Bone-compatibility of Zr-20Nb subjected to AOP at 973 K is better than that of AOP at 1073 K because of the existence of some cracks and partial exfoliation of oxide layer.
抄録全体を表示PDF形式でダウンロード (3919K) -
網野 岳文, 荒河 一渡, 森 博太郎2011 年 75 巻 8 号 p. 460-464
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーRate equation (RE) and kinetic Monte Carlo (KMC) simulation are widely used to understand the accumulation process of lattice defects upon high-energy particle irradiation. RE is more suitable for the simulation of longer term processes in comparison with KMC simulation. However, the accuracy of the results obtained by RE has not yet been clearly established. In the present study, the accuracy of RE for the reaction between self-interstitial atoms and vacancies in a body-centered cubic lattice is verified using a KMC method. The results show that the accuracy of RE reduces when the spatial correlation among defects is not negligible.
抄録全体を表示PDF形式でダウンロード (1164K)
寄書
-
半谷 禎彦, 髙橋 和也, 加藤 弘規, 宇都宮 登雄, 北原 総一郎, 桑水流 理, 吉川 暢宏2011 年 75 巻 8 号 p. 465-467
発行日: 2011年
公開日: 2011/08/01
ジャーナル フリーThe nondestructive quantitative evaluation of pore morphology of porous aluminum, which uses fractal dimensions of spatial distribution of pore area DA, is proposed. The purpose of this paper is to investigate the validity of proposed evaluation by comparing pore morphology in two different types of porous aluminum which were fabricated from different starting materials. It was shown that DA can be expected to provide the sufficient information to quantitatively characterize the morphology of pores in porous aluminum.
抄録全体を表示PDF形式でダウンロード (793K)
- |<
- <
- 1
- >
- >|