Authors: Seung Hoon Nahm, Jeong Min Kim, Jong Seo Park, Kwang Min Yu, Dong Kyun Kim, Am Kee Kim, Dong Jin Kim
1212
Authors: Yoshinobu Shimamura, Keiko Oda, Akira Todoroki, Hideo Kobayashi, Takaomi Inada
Abstract: Bolted joints are widely used for composite structures. As is well known, excessive bearing load gives rise to bearing failure at hole boundaries. Detecting bearing failure is important for assuring integrity of composite structures. Conventional nondestructive inspection methods are expensive, cumbersome, time-consuming, and not suitable for health monitoring, and a simple, low-cost inspection method for bearing failure must be developed. Authors have experimentally demonstrated detection bearing failure by an electrical resistance change method. In this study,
detectablity of remote damage, which includes bearing failure, using an electric resistance change method is investigated analytically. The results show that fiber breaking and delamination induce permanent increase in the electric resistance of the bolted composite joints, and that the proposed method, which involves measuring electric resistance, is effective for detecting bearing failure.
653
Authors: Zhen Lin Lu, Hui Xie, Ji Qiang Gao, Zhi Hao Jin
Abstract: The oxidation behavior and electrical resistivity of reaction-bonded silicon carbide
(RB-SiC) at high temperature (900 °C) had been studied in this paper. The results showed that the
weight of RB-SiC would be increased when it was oxidized at 900. The relationship between the
weight-gain of RB-SiC and oxidation times followed the parabolic curve. The oxidation resistance of
RB-SiC at 900 could increased by the increase of SiC particles sizes. But the electrical resistivity of
RB-SiC had not affected by the oxidation at 900. The oxidation mechanism of RB-SiC and the
affecting factor on oxidation of RB-SiC were analyzed and discussed.
475
Authors: Xiao Qiang Dong, Xiao Hong Bai, Yong Kang Lv
Abstract: As a simplify and effective method , electrical resistivity has been used in geotechnical engineering. In lab the experiment simulated that cemented soil had been polluted by industrial sulphuric acid after mixing. On different age time, the variation trend among electrical resistivity of cemented soil and solution, formation factor and solution concentration were studied. The results indicated that both of electrical resistivity and formation factor have close correlations with sulphuric acid solution concentrations and pollution level of cemented soil. This shows that the electrical resistivity method are very sensitive for groundwater and cemented soil after pollution in the engineering site.
188
Authors: Li Juan Pang, Gang Deng, Xue Feng Zhang, Hui Rong Li, Min Xian Fang, Yu He Li, Song Li Liu
Abstract: Cermets Ti(C，N)80%Co(10-x)% TiC10% Cux%(wt%，x=0，1，2，3， 4， 5) were prepared by powder metallurgy method under vacuum condition at 1500°C and the effects of Cu element to the electrical resistivity and flexural strength were studied in this paper. It turns out the electrical resistivity of the samples obviously decreases with the introduction of Cu element, but the electrical resistivity of the samples increases when the amount of Cu element in the samples becomes more. The flexural strengths of the samples decrease with the amount of Cu element increasing. Ti（C，N）80% Co9%TiC10% Cu1% shows the lowest electrical resistivity and the biggest flexural strength, 7.35*10-7Ω•m and 50.6Mpa. This may be due to the big wetting angle between Cu and the powders of the based body. With the amount of Cu element increasing, the obvious interfaces are made thus the electrical resistivity becomes bigger.
792
