Laminate composites composed of 0.95Pb(Zr0.52Ti0.48)O3-0.05Pb(Mn1/3Sb2/3)O3 piezoelectric ceramic and Fe-Si-B based magnetostrictive amorphous alloy are fabricated, and the effect of control of the areal dimensions and the thickness of the piezoelectric layer on the magnetoelectric(ME) properties of the laminate composites is studied. As the aspect ratio of the piezoelectric layer and the magnetostrictive layer increases, the maximum value of the ME voltage coefficient(αME) increases and the intensity of the DC magnetic field at which the maximum αME value appears decreases. Moreover, as the thickness of the piezoelectric layer decreases, αME tends to increase. The ME composites exhibit αME values higher than 1 Vcm−1Oe−1 even at the non-resonance frequency of 1 kHz. This study shows that, apart from the inherent characteristics of the piezoelectric composition, small thicknesses and high aspect ratios of the piezoelectric layer are important dimensional determinants for achieving high ME performance of the piezoelectric-magnetostrictive laminate composite.

Laminated composite structures have started to play a very significant role in primary and secondary structural weight savings in high performance automobile industries. However, one of the main challenges in implementing these composites is the lack of understanding of the progress of the damage under various loading conditions. In order to understand the influence of design parameters related to the use of composite materials, a proper study of the laminated composite structures requires a complete failure analysis, which includes both initiation and propagation of damage. In this study, a new damage model was developed to predict the progressive damage of the composite, and the progress of damage was investigated by making center-notch and open-hole tensile test specimens for various lay-ups. The simulations, in agreement with experimental tests, indicate that the model is capable of predicting the failure load in open hole composite structures.

In this study, composite laminate cantilever type cylindrical shells with edge-stiffeners are analyzed. A versatile 4-node flat shell element which is useful for the analysis of shell structures is used. An improved flat shell element is established by the combined use of the addition of non-conforming displacement modes and the substitute shear strain fields. Two models by load conditions are considered. Load type A and B are loaded by point load at the free edge and line load respectively. A various parameter examples are presented to obtain proper stiffened length and stiffened thickness of edge-stiffeners. It is shown that the thickness of shell can be reduced minimum 30% by appropriate edge-stiffeners.

판처럼 거동함을 밝히고, 간단한 공식들을 개발하여 발표한 바 있다. 대부분의 교량이나 건물의 상판은 형상비가 큰 경우가 많은데, 이런 구조물의 평형방정식에 대한 종방항 모멘트항(Mx)의 영향은 매우 작아서, 더욱 간단한 해 석이 가능하다. 본 논문에는 이러한 문제들에 대한 연구결과를 제시하였다.