the aim of this study was to determine the microleakage at the cervical margin of the class II composite resin syntac with and without a cervical amalgam base and to compare microleakage restoration at the occlusal margins of restorations and inferface of amalgam and composite.68 extracted sound permanent premolar were used.68 class II slot cavities were prepared in these teth.the teeth were ra...

The impact of a slug of dry sand particles against a metallic sandwich beam or circular sandwich plate is analysed in order to aid the design of sandwich panels for shock mitigation. The sand particles interact via a combined linear-spring-and-dashpot law whereas the face sheets and compressible core of the sandwich beam and plate are treated as rate-sensitive, elastic–plastic solids. The major...

Abstract Impact damage may reduce the mechanical property of honeycomb sandwich composites. In this paper, impact and post-impact shear behavior plates are studied experimentally. The same energy was applied to all six test specimens. region depth crater were measured by using equipment. Shear tests conducted on intact damaged specimens compare their strain fields failure modes. results show th...

In a previous paper from the authors, the bounds from Kelsey et al. (1958) were applied to a sandwich panel including a folded core in order to estimate its shear forces stiffness (Lebée and Sab, 2010b). The main outcome was the large discrepancy of the bounds. Recently, Lebée and Sab (2011a) suggested a new plate theory for thick plates –the Bending-Gradient plate theory– which is the extensio...

The paper presents a locking-free four-node element for laminated composite and sandwich plates based on Refined Zigzag Theory (RZT). Initially, two RZT-based plate elements are derived using eight-node configurations, achieved by way of standard C0 isoparametric shape functions. In addition, with view improving the modelling extremely thin plates, an anisoparametric is developed in which trans...

Carbon fiber-synthetic foam core sandwich composites are widely used for many structural applications due to their superior mechanical performance and low weight. Unfortunately these structures typically have very poor acoustic performance. There is increasingly growing demand in mitigating this noise issue in sandwich composite structures. This study shows that marrying carbon fiber composites...

In this article a new structure of PEM fuel cell end plate is presented. The new structure is known as a honeycomb sandwich panel. Several properties of the presented structure, such as mechanical and thermal behavior, as well as its advantages and disadvantages are introduced. The aim of this paper is to reduce the weight of the while maintaining a better compression force on the PEM fuel cell...

PURPOSE This study evaluated whether a Class II restoration in a flowable resin composite has to be placed prior to (open-sandwich technique) or after (closed-sandwich technique) construction of the interproximal wall in the centripetal build-up technique in order to reduce microleakage. METHODS AND MATERIALS Thirty non-carious molars were selected and randomly divided into two groups (n = 15...

This study deals with the vibration response of sandwich plate with nano-composite core and smart magneto-strictive face sheets. Composite core is reinforced by carbon nanotubes (CNTs) and its effective elastic properties are obtained by the rule of Mixture. Terfenol-D films are used as the face sheets of sandwich due to magneto-mechanical coupling in magneto-strictive material (MsM). In order ...