Metallic bubble wrap could find use in automotive industry
A new type of metallic bubble wrap that is lighter, stronger and more flexible than sheet metal and more heat and chemical resistant than plastic or other polymer-based bubble wraps has been unveiled by researchers at North Carolina State University.
The material is expected to find use in applications such as automobile body panels, the wing edges of airplanes, suitcases, helmets and cases for computers and other electronic devices.
"This material does exactly what sheet metal and other bubble wraps do, but better," said lead researcher Dr Afsaneh Rabiei. "And it won't cost businesses and consumers very much because producing it requires just a few steps."
To create the bubble wrap, Rabiei started with a thin sheet of aluminium and used a studded roller to dot the material with small indentations. Then she deposited a foaming agent into the indentations. When heated, such agents decompose and create bubbles.
Rabiei covered the aluminum with another sheet, sandwiching the foaming agent in its indentation troughs. She then ran a heavy roller over the two sheets to bond them together.
Finally, she placed the combined sheet into a furnace, where the heat broke down the foaming agent and created air bubbles in the material. The process, she says, is akin to baking powder causing batter to rise when baking a cake.
The researchers applied a variety of mechanical tests to the metallic bubble wrap to evaluate its properties and compare it with the original bulk sheet metal.
They found that the bubble wrap, which weighs about 20 to 30% less than the bulk material, offered a 30 to 50% increase in bending strength. In addition, the tensile strength was nearly identical to the non-bubbled metal.
"The way we created this material could be used for any sheet metal, not just aluminium," Rabiei said. "We plan to further develop our metallic bubble wrap and hope it eventually offers better protection for products and the public."
