著者

濱田 泰以

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.66, no.11, pp.811-815, 2017-11-15 (Released:2017-11-20)

参考文献数

2

被引用文献数

1

---

Production technology in traditional industries is inherited in the form of " remember while watching the back of the master." It is a knowledge base of the form of "tacit knowledge", and they need to be formalized by the power of science and technology. Movement of experts is recorded using an infrared camera. The position in the space of the marker affixed to each part of the body of the subject is acquired as digital data. In this report, Kyoto bow showed examples that formalized the tacit knowledge of manufacturing in traditional industries. Kyoto bow is a Japanese bow often used for archery enthusiasts. Mr. Shibata is the 21st bow priest. In order to elucidate the tacit knowledge, he possessed, vibration tests and bending tests were conducted. Test results proved that materials with high modulus of elasticity were chosen when Mr. Shibata chooses materials.

著者

畑 敏雄

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.17, no.175, pp.322-325, 1968-04-15 (Released:2009-07-09)

参考文献数

12

被引用文献数

2 3

---

Two theories of fracture of viscoelastic materials are hereunder proposed, the one based on a simple model and the other generalized thereupon, and an attempt is made to explain the dependence of stress and strain at break on temperature and strain rate as particularly was called the failure envelope by T.L. Smith.The model of the first simple theory consists of two Maxwell elements (system 1 and 2) connected in parallel and the following criteria for fracture are introduced.(1) Fracture occurs first at the system 1, and then at the system 2 where the whole load is applied.(2) Fracture of the system 1 occurs either when the spring reaches the critical strain ε11c (in the case of large strain rate) or the dashpot does so to ε12c (in the case of small strain rate).For the deformation of constant rate R, the following results are obtained, which explain the experimental behaviors well at least qualitatively.at larger strain ratesat smaller strain rateswhere σ, ε, G and τ follow the ordinary use and suffices 1 and 2 mean system 1 and 2 respectively and the suffix b does so "at break".Next the above model theory is so extended to the generalized Maxwell bodies as to read that the stress of deformation at constant rate is expressed by the equationIn this case the storage energy Wst and the dissipation energy Wdis of deformation are calculated after Landel, and the following criterion is introduced, that is, the sample breaks either when the elastic part with its own modulus G0 (the instantaneous modulus) reaches the critical strain ε1c or the viscous part with its steady flow viscosity η0 reaches the critical strain ε2c.The results are given asat larger strain ratesat smaller strain rateswhere G' and η' are dynamic modulus and viscosity respectively. Considering the dependence of G' and η' on shear rate and temperature, the failure envelope can be explained with these equations.

著者

宮田 昌悟 田中 基嗣

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.63, no.9, pp.684-689, 2014-09-15 (Released:2014-09-20)

参考文献数

39

被引用文献数

1

著者

牧 正志 田村 今男

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.30, no.329, pp.211-217, 1981-02-15 (Released:2009-06-03)

参考文献数

35

被引用文献数

8 11

著者

熊倉 郁夫

出版者

社団法人日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.52, no.5, pp.552-553, 2003-05-15

参考文献数

6

著者

岡島 智史 泉 聡志 酒井 信介

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.57, no.4, pp.401-407, 2008 (Released:2008-04-18)

参考文献数

6

被引用文献数

1 1

---

Because of the lessening number of maintenance experts, a method to rationalize pipe inspection interval is desired. For this purpose, the evaluation method for the pipe integrity in the form of failure probability has been developed based on the Bayesian inference method in the previous paper. In this paper, the previous method is called the linear-Bayes method. The linear-Bayes method assumes wall thinning due to Flow Accelerated Corrosion (FAC) as the principal damage mechanism, and it can define the safety margin of a pipe's residual life depending on the number of inspections. However, the linear-Bayes method ignores the corrosion rate fluctuation against time, which may be caused by the change of environment such as water chemistry and flow velocity. Therefore, the linear-Bayes method may underestimate the failure probability of the pipe segments if the online monitoring of the environments is not used. In this paper, the linear-Bayes method is extended for the wall-thinning model with the corrosion rate fluctuation. The extension is carried out through following two approaches : correction-term and error-term approaches. In this paper, the formulation and the procedure for each approach are shown at first. And then, the accuracy and the merit of the extended method are examined through the evaluation using the artificial and the actual inspection records. Through the examination, it is confirmed that the extended method makes the evaluation of the pipe integrity available in view of safety margin for the corrosion rate fluctuation, keeping the merits of the linear-Bayes method.

著者

菊地 慎二 平島 健一 杉坂 憲明

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.47, no.9, pp.887-891, 1998-09-15 (Released:2009-06-03)

参考文献数

6

被引用文献数

2 1

---

This paper presents a unified analysis of isotropic out-of-plane shear problems with concentric circular elastic inclusions. The applied disturbances considered in this paper are longitudinal shear stress at infinity, analysis is based on the complex variable method using the Möbius transformations by Honein and Herrman. Several numerical examples are given by many graphic representation.

著者

久保 司郎

出版者

社団法人日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.32, no.362, pp.1285-1291, 1983-11-15

被引用文献数

1

著者

荒川 正文

出版者

社団法人日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.16, no.164, pp.319-321, 1967-05-15

被引用文献数

2

---

粉体粒子の付着、凝集の程度を知るためにいくつかの方法が試みられているが、その中で粉体充てん層のせん断応力と荷重の関係からクローン式により粒子間凝集力を測定する方法を試みた。この方法で得られる凝集力はせん断面あたりの力であるが、これに充てん層の空隙率、試料粒子の平均粒子径、粒子1個に対する隣接粒子の平均接触点数を考慮すれば粒子接触点1個の凝集力を計算することができる。粒度の異なった数種のホワイトアランダムを試料としてこの方法で粒子径と粒子間凝集力の関係を調べた。その結果、この試料では脂肪酸処理による粒子の表面の疎水化の効果はほとんど認められない。また、粒子径が小さくなるほど凝集力も減少するが、その力は吸着層を伴ったvan der Waals力の範囲である。しかし、van der Waals力による凝集力は粒子径に比例するといわれるが、この実験では微粒子では粒子径が1/10になると凝集力が1/100程度になった。これは、充てん層のせん断面あたりの凝集力を粒子接触点1個あたりに換算するときに用いたRumpfの仮定に誤りがあると考え、実験結果から逆に補正をすると高空隙率充てんの微粉体では粒子1個の平均接触点数が約2.3となり、微粒子の凝集は珠数状の連りで、かさ高い網状構造を形成していることが推定される。

著者

佐藤 千之助 車田 亮 岩城 英彦 小松 靖門

出版者

社団法人日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.35, no.397, pp.1144-1150, 1986-10-15

被引用文献数

1

---

Two kinds of carbon felt reinforced carbon composite of pitch fiber (C/C-A) and of PAN fiber (C/C-B) have been developed to improve the fracture mechanics properties of regular grade graphite. The tensile properties and the fracture toughness values of these new composites were determined as function of temperature up to 2400℃. These results were compared with those of a carbon fiver cloth reinforced carbon composite of rayon fiber (C/C-C) and fine grain isostatic graphite (IG-11), and these distinctive features were discussed.

著者

赤井 浩一

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.15, no.155, pp.523-530, 1966-08-15 (Released:2009-06-03)

参考文献数

9

著者

塩野 剛司 佐藤 ひろゆき 森谷 幸紀 岡本 泰則

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.59, no.6, pp.409-412, 2010-06-15 (Released:2010-06-19)

参考文献数

9

被引用文献数

1 1

---

Tsuchi-kabe (called as soil wall or mud wall in English) utilized in Japanese traditional buildings is well known to have the characteristics of humidity conditioning. However, the characteristics have not been well examined. For preparing tsuchi-kabe material, soil, sand and rice straw are well mixed with water and then kept from a few weeks to months to promote fermentation. This aging process that is called as “Nekashi” gives plasticity to the material and is very important to construct tsuchi-kabe. In the present study, effect of “Nekashi” on the characteristics of humidity conditioning was examined. Long period of “Nekashi” enhanced the characteristics in nakanuri-kabe with a smaller amount of clay component.

著者

向山 和孝 花木 宏修 中村 裕紀 境田 彰芳 岡田 憲司 伊藤 勉 菅田 淳 酒井 達雄

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.67, no.2, pp.136-142, 2018-02-15 (Released:2018-02-20)

参考文献数

15

被引用文献数

3 2

---

A statistical estimation method of S-N curve for aluminum alloys using their static mechanical properties was proposed. Firstly, S-N data series for aluminum alloys were extracted from "Database on Fatigue Strength of Metallic Materials" published by the Society of Materials Science, Japan (JSMS) and semi-logarithmic curve model was applied as mathematical regression model based on the JSMS standard, "Standard Evaluation Method of Fatigue Reliability for Metallic Materials -Standard Regression Method of S-N Curves-". Secondly, correlations between each pair of regression parameters and static mechanical properties were investigated. Using these correlations, S-N curve for aluminum alloys could be predicted easily from the static mechanical properties. Moreover, using (1) the distribution of regression parameter D and (2) the distribution of fatigue strength at 107 cycles, the percent points for the predicted S-N curve was evaluated. As result, it was confirmed that over 70% of S-N data series of wrought aluminum alloys fall within the range of estimated interval between -3s and +3s, where s means a standard deviation for the parameter of D.

著者

多田 直哉 大谷 隆一 柴田 昌宜 小林 智光

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.50, no.2, pp.129-136, 2001-02-15 (Released:2009-06-03)

参考文献数

9

被引用文献数

2 3

---

Fatigue tests were conducted at 1273K using smooth bar specimens of a nickel-based single crystal superalloy CMSX-10, and small cracks were observed on the surface of the specimens by means of microscope. It was clarified by the observation that fatigue fracture of CMSX-10 takes place as follows; (1) Oxide-layer was formed on the surface of the specimen. (2) A lot of small cracks of the size of about 100μm were initiated perpendicular to the stress axis on the surface of the oxide-layer. (3) Some of them grew and penetrated the oxide-layer to reach the base metal. Processes (1) to (3) were completed at the very early stage of fatigue life. (4) Growth of the cracks that reached the base metal brought about the final fracture. As the formation of oxide-layer on the surface of the specimen was considered to be a trigger of crack initiation, a fatigue test was also conducted with repeated removal of the oxide-layer by emery paper and diamond paste. In this test, no crack appeared on the surface of the specimen even at 20000 cycles when a lot of cracks were observed in the normal fatigue tests. This proves that removal of the oxide-layer retards the initiation of small cracks and extends the fatigue life.

著者

山田 正

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.28, no.312, pp.910-916, 1979-09-15 (Released:2009-06-03)

参考文献数

46

著者

後藤 輝男

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.16, no.169, pp.809-818, 1967-10-15 (Released:2009-06-03)

参考文献数

97

著者

中村 篤智

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.71, no.9, pp.742-748, 2022-09-15 (Released:2022-09-20)

参考文献数

19

---

It is well known that light environment affects the mechanical properties of inorganic semiconductor materials, but still little is understood about the detailed mechanism. We before reported that single-crystalline zinc sulfide, an inorganic semiconductor material, exhibits significant plasticity in the dark. This finding has prompted us to investigate the effect of light environment on the dislocation behavior of inorganic semiconductor materials once again. On the other hand, in understanding the effects of light environment on dislocation behavior, it is difficult to obtain large, millimeter-sized crystals of advanced inorganic semiconductor materials to which conventional mechanical tests can be applied. Therefore, one of the main goals of our research project is to establish a method to understand dislocation behavior at the nanoscale by constructing a new nanoscale mechanical testing system that can be applied to thin substrates under controlled light environment. We have successfully constructed a new nanoindentation system (we call Photoindentation) in which light can be quantitatively applied below the indenter from two directions at the same time, and conducted creep tests in which a constant load is applied at or above the load at which dislocations occur (pop-in stress). In addition, care was taken to obtain statistically correct experimental results by conducting a great number of experiments. As a result, it was demonstrated that light has little effect on the nucleation of dislocations, while light has a strong effect on the glide motion of dislocations. In addition to these nanoscale experiments, macroscale experiments have been conducted in an effort to further understanding of light environment effects on dislocation behavior.

著者

藤井 太一

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.16, no.163, pp.257-267, 1967-04-15 (Released:2009-06-03)

被引用文献数

1 1

著者

森 稔

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.25, no.278, pp.1077-1085, 1976-11-15 (Released:2009-06-03)

参考文献数

156

著者

矢代 茂樹

出版者

公益社団法人 日本材料学会

雑誌

材料 (ISSN:05145163)

巻号頁・発行日

vol.72, no.3, pp.270, 2023-03-15 (Released:2023-03-20)