Leveraging a well-hyped but still-emerging science, two Johns Hopkins University engineers have launched a company that uses special equipment to manipulate material a few atoms at a time.

The commercial applications of this kind of science, called nanotechnology, are vast, yet also highly speculative. Investors are excited about the possibilities of creating materials that today are only pipe dreams, with some wondering whether nanotech could drive the next boom in high-tech spending and innovation, but they are moving forward cautiously.

In the case of Reactive NanoTechnologies, the founders say they have discovered a way to create a metal foil that can be heated to 1,500 degrees centigrade, using nothing more than a nine-volt battery as a power source. Only the foil, and anything touching it, would be heated via this process.

Why would anyone want to do such a thing? Because the foil — which is nothing more than a thin metal disk of nickel and aluminum, demonstration models of which are not much bigger than a coin — can be inserted between materials that manufacturers want to fuse together, serving as a kind of welding agent when the foil is heated.

“You could call it atomic science because we’re working with nanometers — an atom is about two-tenths to three-tenths of a nanometer,” said Timothy P. Weihs, the CEO, president and co-founder of Reactive NanoTechnologies. “I’d call this almost atomic engineering.”

But for Reactive, this is no mere science experiment.

A decade in the making, the company is now preparing to move out of its “virtual” office at Baltimore’s Emerging Technology Center incubator (as a practical matter, its real office is at Hopkins’ Homewood campus), and into permanent space. It has landed several beta clients. And it is finalizing its first round of venture capital investment, a $2 million infusion led by Toucan Capital Corp.

Weihs and his co-founder, Omar Knio, decline to name their clients, but their initial targets include the military and electronics makers. Both have an interest in Reactive’s high- temperature foils because they solve a problem that arises in attempting to fuse ceramic and metal materials.

The laws of physical science demand that ceramic and metal expand when they’re heated and contract when they cool. The problem is that metal does both of these to a larger extent, making it difficult to weld the two together.

“We overcome that because we don’t heat the elements — we just heat the foil,” says Weihs.

The foil is inserted between the two elements to be fused, along with solder, easily melting the materials together without melting anything else. A cell phone manufacturer could fuse the metal and ceramic components of its product by putting both in a furnace, but the result would be a liquefied phone.

Robert F. Hepfield, a managing director of Toucan Capital in Bethesda, said venture capitalists are interested in such technology for two reasons: First, the science has reached the stage where viable commercial applications are beginning to come into focus, and second, because those applications are plentiful. Since nanotechnology allows for the creation of new types of previously unproduceable materials, the possible applications are limited only by the imagination.

“The more [scientists] learn, the more they expect nanoscience and nanoengineering will become as socially transforming as the development of running water, electricity, antibiotics and microelectronics,” intones the National Science Foundation’s National Nanotechnology Initiative, in a recent report. The NNI asks: “What if we could build things the way nature does: atom by atom, molecule by molecule?”

What if, indeed. But it isn’t the mere ability to manipulate atoms that interests the investment world, according to Hepfield.

“When you strike a match, you’re manipulating material at an atomic level,” he said. “It’s the ability to control that that’s really exciting here.”

Still, he cautions against getting too excited.

“We’ve looked at probably 20 business plans that say they work with nanotechnology, and only one or two are even close,” he said. “There’s a lot more hype than reality, but that’s OK. That’s how it always starts.”

He declined to talk about Reactive because the venture fund’s investment in the startup is not yet final. But it’s fair to say that if anything, the reality of the company appears to outstrip the hype for a change, since Reactive, with its glorified soldering iron, is currently exploiting only a sliver of the possible nanotechnology universe.

Yet it’s a promising sliver. The military wants to fuse its new ceramic armor to its old metal tanks, but that’s a problem Reactive may be able to solve. Makers of electronic gadgets, such as cell phones and personal digital assistants, use adhesives, not ovens, to fuse the metal and non-metal components of their machines, but that’s limiting.

“For now, it works,” said Knio, Reactive’s vice president of research and development. “But as processors shrink … this glue has been the limitation [to miniaturization]. It works, but it’s becoming more and more of a disadvantage.”