Foam Shrinkage
Foam Shrinkage - Related Videos
07:56
Preparation of Carbon Fiber and Bamboo Fiber Reinforced Poly (butylene Adipate-co-terephthalate) Foams by Supercritical Carbon Dioxide Foaming
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2025
This study describes a supercritical carbon dioxide foaming method for the preparation of carbon fiber and bamboo fiber reinforced poly (butylene adipate-co-terephthalate) foams.
01:27
Shrinkage in Concrete
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2024
Shrinkage in concrete is primarily due to water loss from evaporation, hydration of cement, or carbonation, leading to a reduction in volume. The volumetric contraction results in volumetric strain in concrete. However, in practice, shrinkage is measured as linear strain, which is one-third of the volumetric strain. When concrete is still in its plastic state, it can undergo a decrease in volume by about 1% of its absolute volume. This decrease is known as plastic shrinkage. It arises either...
01:21
Drying Shrinkage
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2024
When hardened concrete is exposed to air with a relative humidity of less than 100 percent, it begins to lose the free water within its capillaries. As this water evaporates, the water initially adsorbed onto the calcium silicate hydrates migrates towards these now empty spaces and eventually evaporates as well. Over time, as more water leaves, the volume of the concrete decreases, a phenomenon known as drying shrinkage. A portion of this drying shrinkage can be reversed; if the concrete is...
01:24
Carbonation Shrinkage
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2024
Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage. The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction facilitates the...
01:25
Shrinkage, Obsolescence, and Holding Costs
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2025
In inventory-based businesses, profitability often depends on more than just sales volume or procurement efficiency. Hidden costs tied to inventory management—specifically shrinkage, obsolescence, and holding costs—can significantly erode margins if left unmanaged.Shrinkage occurs when inventory is lost due to theft, damage, or administrative errors. Even with advanced tracking systems, discrepancies remain a persistent issue, especially in retail. Regular audits, employee training, and...
FAQs
Pressure differences create a driving force for gas to leave foam cells, reducing the internal support that maintains cell dimensions. As gas escapes, the structure can contract, and its density, permeability, and mechanical strength may change. For engineering design, linking pressure conditions to dimensional change helps explain why a foam may lose performance during processing or service.
Cooling, solvent loss, and moisture loss can destabilize the balance inside a foam, even when cell walls have not initially ruptured. Surfactant instability can further reduce cellular stability, while coalescence or rupture removes barriers between cells. These mechanisms matter because shrinkage may arise from environmental or structural changes as well as direct gas loss.
The consequences of Foam Shrinkage depend on the material being engineered. In polymeric, metallic, cementitious, and liquid foams, the same dimensional change can affect different performance goals, including insulation, cushioning, structural behavior, or durability. Engineers therefore evaluate shrinkage in relation to the material's intended function rather than treating volume change as an isolated measurement.
Assessment begins by measuring changes in foam volume or dimensions and relating them to changes in density, permeability, and mechanical strength. Engineers can then compare those outcomes with the processing conditions that produced them. This approach supports control of manufacturing conditions and helps identify whether dimensional change threatens insulation, cushioning, structural performance, or long-term durability.
Foam Shrinkage studies are especially relevant when a product must retain its geometry over time or through manufacturing. Construction materials, packaging, transportation components, and energy-related systems may depend on stable insulation, cushioning, or structural performance. Testing shrinkage in these contexts helps engineers judge whether dimensional changes could reduce product durability or reliability.
Engineers use shrinkage measurements to characterize dimensional change and predict long-term behavior. By examining pressure differences, cooling, solvent or moisture loss, surfactant stability, and cell-wall damage, they can connect a processing condition with the resulting structural change. That connection supports more reliable processing conditions and more durable material designs.