Flexible Polyurethane (PU) foam samples with different densities and chemical formulations were tested in quasi-static stress-strain compression tests. The compression tests were performed using the Lloyd LR5K Plus instrument at fixed compression strain rate of 0.033 s-1 and samples were compressed up to 70% compression strains. All foam samples were tested in the foam rise direction and their ...

The mechanical strength of an Al-30% Si alloy in the mushy zone was estimated by using a novel centrifugation apparatus. In the apparatus, the alloy melt was partially solidified, forming a porous structure made of primary Si platelets (Si foam) while cooling. Subsequently, pressure generated by centrifugal force pushed the liquid phase out of the foam. The estimated mechanical strength of the ...

Waves on the ocean are generated well away from any shoreline and travel under a prevailing wind towards a distant shore. These deep-water waves eventually become shallow-water waves and break near the shore creating a turbulent surf front of bubbles, foam and spray, encompassing secondary breaking and smaller splashing waves. Human surfers can propel themselves shorewards on these breakers or ...

In this study, free vibration of a foam-core orthotropic smart composite cylindrical shell (SCCS) filled with a non-viscous compressible fluid, subjected to combined electro-thermo-mechanical loads is investigated.  Piezoelectric polymeric cylindrical shell, is made from polyvinylidene fluoride (PVDF) and reinforced by armchair double walled boron nitride nanotubes (DWBNNTs). Characteristics of...

Foam injection is becoming a standard conditioning agent when tunnelling with an earth-pressure balanced shield, resulting in an increasing interest in this technique. The technique is mostly based on empirical rules and experience. To be able to determine what foam and how may foam has to be injected for different soils, it is necessary to know the mechanical parameters of the foam-water-soil ...

sandwich panels as composite materials have two external walls of either metallic or polymer type. the space between these walls is filled by hard foam or other materials and the thickness of different layers is based on the final application of the panel. in the present work, the extent of variation in core density of polyether urethane foam and subsequent flexural and compressive changes in s...

Carbonate apatite (CO₃Ap) foam has gained much attention in recent years because of its ability to rapidly replace bone. However, its mechanical strength is extremely low for clinical use. In this study, to understand the potential of gelatin-reinforced CO₃Ap foam for bone replacement, CO₃Ap foam was reinforced with gelatin and the resulting physical characteristics were evaluated. The mechanic...

How can the large power needs of future electric ships for propulsion, radar, and weapons systems be met given the prohibitive size and weight of the required number of standard 60 Hz AC generators and transformers? A solution may lie in a rugged, efficient, and compact solid-state, 10-20 kV Medium Voltage DC (MVDC) circuit breaker (Figure 1). In this paper, Diversified Technologies, Inc. will ...

Aluminum foam has received considerable attention in various fields and is expected to be used as an engineering material owing to its high energy absorption properties and light weight. To improve the mechanical properties of aluminum foam, combining it with dense tubes, such as aluminum foam-filled tubes, was considered necessary. In this study, an aluminum foam-filled steel tube, which consi...