著者

市川 昌弘 高松 徹 松尾 貴史 岡部 永年 阿部 豊

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.42, no.483, pp.1406-1411, 1993-12-15

被引用文献数

2 2

---

Rolling fatigue tests were carried out on hot isostatically pressed silicon nitride bearing balls.At three load levels of the maximum Hertzian contct pressure p_<max>=5900,6740 and 7110 MP_a,13 balls each were tested,and the life distribution was studied.It was found that the rolling fatigue life followed approximately a 2-parameter Weibull distribution with the shape parameter of a 〓 1 at each load level.The relationship p^k_<max>L_<50>=const(x〓10) was found between p_<max> and the median life L_<50>.Microscopic observationof flaking was also performed,and two types of flaking were found.One is flaking with the depth of the order of 100μm,and the other is a shallower one.The depth of the former type was found to coincide aproximately with the depth at which the maximum shear stress ocurred.At lower load levels,the former type was dominant.Frequency of appearance of the latter type increased with an increase in load level.Comparing the shape parameter of a〓1 and the exponent of x〓10 mentioned above with those for the cylic bending fatigue of plain specimens of silicon nitride,it was suggested that the mechanism of rolling fatigue of silicon nitride was different from that of cyclic bending fatigue of the same material.

著者

村上 澄男

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.48, no.3, pp.317-318, 1999-03-15

著者

座古 勝

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.39, no.447, 1990-12-15

著者

超合金とコーティング強度評価WG(岡崎)

出版者

社団法人日本材料学会

雑誌

学術講演会講演論文集

巻号頁・発行日

vol.52, pp.53-54, 2003-05-16

著者

平井 恒夫

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.35, no.392, pp.557-558, 1986-05-15

著者

菅谷 達 倉本 聡 佐藤 千明

出版者

社団法人日本材料学会

雑誌

学術講演会講演論文集

巻号頁・発行日

vol.61, pp.361-362, 2012-05-25

著者

小川 欽也 杉山 文子

出版者

社団法人日本材料学会

雑誌

材料 = JOURNAL OF THE SOCIETY OF MATERIALS SCIENCE, JAPAN (ISSN:05145163)

巻号頁・発行日

vol.53, no.5, pp.560-565, 2004-05-15

参考文献数

7

被引用文献数

2 7

---

The Split Hopkinson pressure bar (SHPB) method has been used for impact tests such as compression and shearing, and is currently modified for tensile test, since the various kinds of high strength sheet metals are greatly concerned with the safety and the energy saving demands for high velocity vehicles. Evaluation of mechanical properties by a tensile test using the SHPB, however, has not been clarified, since the testing conditions such as specimen geometry and settings are quite different from the usually operated compression version. In the present paper, we try to identify the characteristics of the method, particularly such as a yielding phenomena, and have clarified the effect of three dimensional stress wave propagation in the tensile test where a large ratio of sectional areas between a specimen and a loading bar is usually inevitable.

著者

松島 康 可児 弘毅

出版者

社団法人日本材料学会

雑誌

材料 = JOURNAL OF THE SOCIETY OF MATERIALS SCIENCE, JAPAN (ISSN:05145163)

巻号頁・発行日

vol.53, no.3, pp.278-282, 2004-03-15

参考文献数

15

---

Shock induced polymorphic transition of pure iron (99.5%) has been investigated experimentally using in-material self-made manganin gauges which has a shape of one-turn coil. A negative pulse is superposed on an output signal from the gauge in the pressure range above about 18GPa. The negative pulse is thought to be originated in shockinduced polymorphic transition (&alpha;-&epsilon; phase transition) because the polymorphic transition is followed by magnetic transition (ferromagnetic to paramagnetic). The iron plate specimens between which a manganin gauge is sandwiched are magnetized in the vicinity of the gauge by constant current applied to the gauge. The polymorphic transition behind shock front reduces magnetic flux near the gauge when the shock front passes through the gauge. This flux reduction generates the negative pulse. From the negative pulse superposed on a gauge signal, information on the polymorphic transition can be obtained. Experimental data show that the negative pulse appeared in the pressure range above 18GPa and the amplitude of the pulse increased with the applied pressure. It is inferred from the discussion about experimental data that the maximum rate of transition increases with applied pressure.

著者

中村 信夫

出版者

社団法人日本材料学会

雑誌

材料試験 : journal of the Japan Society for Testing Materials (ISSN:03727971)

巻号頁・発行日

vol.6, no.50, 1957-11-15

著者

黒掘 利夫 竹内 望

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.391, pp.441-445, 1986-04-15

被引用文献数

1

---

An investigation of stable laser action at room temperature using the F_2 Centers of LiF : Mg crystals is presented. A remarkable reduction in fading of the output signal intensity has been achieved by adjusting the Mg impurity level to an appropriate quantity and by optimizing F_2 Center concentration. It is found that magnesium ions in LiF crystals play a role for suppressing the fading of laser action due to the two-step photoionization process. It is also found that the fading strongly depends on intracavity power and temperature.

著者

田中 啓介

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.38, no.432, 1989-09-15

著者

楠本 韶 木村 宣夫 木寺 享 竹内 博文

出版者

社団法人日本材料学会

雑誌

学術講演会前刷

巻号頁・発行日

vol.32, pp.183-185, 1983-05-24

著者

大塚 昭夫 宮田 隆司

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.33, no.364, pp.97-103, 1984-01-15

著者

小林 英男

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.363, pp.1410-1415, 1983-12-15

著者

青木 繁

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.33, no.365, pp.229-235, 1984-02-15

被引用文献数

1

著者

McEVILY A. J. Jr. MAY Iain Le

出版者

社団法人日本材料学会

雑誌

Materials science research international (ISSN:13411683)

巻号頁・発行日

vol.8, no.1, pp.1-8, 2002-03-15

被引用文献数

1

---

This paper discusses the sequence of events involved in the accident which took place at the Three Mile Island Nuclear Plant in Pennsylvania, USA in 1979, the worst nuclear disaster in US history. The physical characteristics of the as-built reactor building are described, and the changes brought about by the accident on the plant structure are discussed. The current state of the plant and the materials of the reactor are also discussed.

著者

井上 達雄 伊藤 博明 向井 竜二

出版者

社団法人日本材料学会

雑誌

学術講演会講演論文集

巻号頁・発行日

vol.59, pp.267-268, 2010-05-21

著者

上原 拓也 井上 達雄

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.44, no.498, pp.309-315, 1995-03-15

被引用文献数

1 9

---

The quenching process of a Japanese sword is simulated by a CAE system "HEARTS" developed by one of the authors. The system is available to consider the coupling effect among metallurgical change due to phase transformation, temperature and inelastic stress/strain. In the quenching process of the Japanese sword, a special kind of clay is pasted on the surface to control the heat transfer coefficient between metal and water. The dependence of the coefficient on the thickness of clay and also the surface temperature is experimentally evaluated first by using a cylindrical rod of silver. The results show a relatively higher value with thin-pasted clay than that without clay at a high temperature range. The data are then applied to simulate the variation of temperature coupled with the structural change from austenite to martensite and pearlite as well as the variation of stress. It gives an attractive result that the sword is bent two times to the direction opposite to the normal shape due to the complicated time difference between martensitic and pearlitic transformation and thermal contraction. The simulated results of residual stress distributions are compared with the measured data by X-ray diffraction technique.

著者

浅田 和雄 高橋 浩昭 高橋 尚志

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.41, no.468, pp.1396-1402, 1992-09-15

---

When a projectile with high velocity impacts onto a target, several fracture modes (such as spall fracture, plug fracture, penetration fracture and so forth) appear in the target. Therefore, in order to identify an impact fracture strength of materials, a particular type of impact experiments should be undertaken. For example, an impact experiment for flying plate is suitable to determine the spall fracture strength. Different impact conditions, however, may bring in different fracture strength even for the same target material. For the purpose of clarifying perforation dynamics (mechanism) by means of computer code, it is necessary to provide a unified fracture condition which enables to explain all modes of spall fracture, plug fracture and penetration fracture. Under this fracture condition, fracture takes place when the strain has attained its critical value, which may be affected by pressure and temperature. In the present study, the unified fracture condition was examined through comparison between the back surface velocity of flying plate impact experiment and the velocity calculated from computer code by using Ni-Cr-Mo steel (SNCM-630 steel). The computer code used here was that of one -dimensional large deformation stress wave propagation by finite-difference-method. The experimental results and computer code results were well in accord with each other, confirming the applicability of the unified fracture condition to perforation dynamics.

著者

座古 勝 辻上 哲也 北村 貴典

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.44, no.499, pp.390-394, 1995-04-15

被引用文献数

1

---

It is well known that the mechanical properties of laminated composites depend on the stacking sequences. As the bending modulus of elasticity is affected remarkably by the stacking sequences, the stress and strain analyses for laminated composite structures require a special technique. Therefore, a new analytical method has been proposed in order to calculate the mechanical behavior of laminated structures in this paper. The proposed method has been applied for a laminated composite structure as a numerical example. As a result, it has been recognized that the numerical behavior of the composite structure with anisotropic properties under mixed loads of bending and tension can be analyzed by the proposed method, even if it has two different moduli of elasticity of bending and tension. In addition, CPU time of FEM based on the proposed method can be reduced remarkably as compared with ordinary FEM.