Julia Carpenter

Julia Carpenter, 33, invented a simple, cost-effective way to make a foam-like material out of metal that has a thousand times more surface area than any of its predecessors. The new material could serve as a heat sink and reduce the amount of energy required to cool microprocessors and other electronics. 

Right now, around 40% of the energy used by data centers—such as servers for AI, cloud computing, and crypto currency—goes toward cooling. Similar cooling methods are used in industrial manufacturing and the batteries in electric vehicles. 

For decades, electronics have been cooled by systems that circulate liquid or air through heat sinks built from sheets of solid metal, or by using refrigerants and compressors. Both types of systems are costly to build, maintain, and run. They’re also prone to failure, and their creation emits significant greenhouse gases. 

Metal foams have existed for nearly a century, but until now they were produced using an expensive multistep process that involved making a plastic template and replacing it with metal. As a result, their commercial use has been limited. 

“We changed the process fundamentally,” says Carpenter.

Carpenter’s process starts with a slurry of metal particles infused with bubbles as small as 1 micron—she’s used iron, nickel, and stainless steel, among others—that she essentially pipes into a lattice-like structure with various sized holes. “It’s like making meringue in the kitchen,” she says.

Once air-dried, the material is heated to between 600 °C and 1,700 °C to solidify the structure into something so highly porous that it can float.

To get her technology into the market, Carpenter started Apheros, in her native Switzerland—and industrial clients immediately lined up.