Papers by Keyword: Compressive Performance

Abstract: The compressive capacity of composite foam sandwich tube is influenced by the fabrication process. Foam sandwich composite tube is made with technology of filled foam precut and curing molding together with prepreg ply. In order to clarify the interface to the bearing capacity, dynamics finite element software LS-DYNA was used to simulate the model whose interface is polished and waxed or not. The delamination was observed by the deformation cloud picture and displacement difference curve. The simulation showed that the composite foam sandwich tube which interface was polished and waxed before it was formed has relatively higher carrying capacity than that none-polished and none-waxed.

Abstract: Composite foam sandwich tube, which is a sandwich structure, improves stability of the tube and strength for use compared with single-layer composite, and is available in civil engineering as bearing member of light weight, high strength, and corrosion resistance. Axial compression experiment was made for fiber reinforced resin matrix composite foam sandwich tube which is laid in 5 different ways, and the comparing analysis on damage models was made according to experimental phenomenon. The laws of influence is preliminarily recognized by analyzing influence to foam sandwich tube of fiber laying, modulus of fiber, three dimensional elastic modulus ratio, tube radius, tube thickness.

Abstract: Through compressive test on 18 polyurethane composite panels in 4 groups, observing their failure characteristics under compression, getting test result on compressive performance and load-deformation curve, analyzing failure reason, which will set the foundation for further experimental study and theoretical analysis.

Abstract: Underwater blast injury is a common war injury during combat around islands or fighting for beachhead, and is also ordinary in underwater engineering construction blast. Adding an extra underwater blast wave protection layer and Integration with life jacket is a reasonable protection measure. Four different low mass density closed cell polyurethane foams used in life jacket have been tested by quasi-static material testing machine, and the dynamic mechanical behavior at strain rates of 10-3～10-1s-1 has been analyzed. The yield strength has been tested with Split Hopkinson Pressure Bar. Experimental results show that the compressive performance of the polyurethane foam is sensitive to the strain rates. The polyurethane foams’ yield strength shows rising trend along with strain rates increase. Under the condition of the plateau yield strength below human’s allowable pressure, the energy absorption performance of the polyurethane foams has been analyzed and in contrast.

Abstract: Metal rubber material is a new type of elastic and porous material which develops from metal materials. The macro-structure of metal rubber is reticular just as high polymer, made up of fine metal wires. In this paper, the testing equipment which can test micro-motion of metal rubber is designed and the compressive force-displacement curve along molding of metal rubber has gain. The cure along molding of metal rubber has three different characteristic stages. In different characteristic stages, the deformation of metal rubber material has different micro physical mechanism. The micro physical mechanism of different deformation periods is summarized by the micro analyses of three different characteristic curve stages and the study of metal rubber molding technology. Based on the manufacture technology and molding process, the spring wires in metal rubber material have contacted adequately after molding. The micro physical mechanism of metal rubber material in this stage is produced by blank tear combination deformation in linear elastic of spring wires. Because of the deformation stage is very little; the stiffness of metal rubber material is represented linear characteristic in this stage. The contacted points of spring wires are slide along with deformation increasing. The stiffness of metal rubber material is reduced after early linear deformation stage. The compressive force-displacement curve represents soft characteristic stage in macro- expression. When the most contacted points of spring wires are slide along with deformation increasing, the stiffness of metal rubber material is rapid rise. The exponential reinforcement stage is caused by the strongly constraints among spring wires. The micro physical mechanism can explain the different characteristic stages of metal rubber material on compressive performance.