Nanoporous copper for improved military detonators

Scientists at the Georgia Tech Research Institute, and the Indian Head Division of the US Naval Warfare Center, have developed copper structures with nanoscale pores that could play a key role in the next generation of smart weapons.

The ‘smartness’ of modern munitions lies largely in the micro-electromechanical (MEMS) fuses used to control the detonation of the primary explosive. Reduce the size of the fuses, and you can produce smarter, more efficient weapons that require less explosive material, better focus the detonation, and reduce collateral damage.

This nanoporous copper structure is a precursor material for explosive compounds used in military detonators

Georgia Tech researcher Jason Nadler uses templates such as microspheres and woven fabrics to create regular patterns in copper oxide paste. He then converts the resulting oxide structures to pure metal, retaining the patterns set by the template. In this way Nadler has made structures with structural components that have nanoscale pores.

Nadler’s inspiration is more than just practical. He says: “Among my personal research interests are links between engineered multi-scaled porous materials and the hierarchical organisation found in many biological structures. I find nature’s ability to optimise architectures on a wide spectrum of length scales simultaneously very inspiring.”

With the latest development, the amount of primary explosive could be reduced by at least two orders of magnitude, according to Gerald Laib, the Indian Head scientist who invented the MEMS Fuze concept. “This development will also vastly reduce the use of toxic heavy metals and waste products, and increase the safety of weapon production by removing the need for handling bulk quantities of sensitive primary explosives.”

Nadler’s copper structures will be incorporated into integrated circuits, and then chemically converted to millimetre-diameter explosives. All this can be scaled and integrated into standard microelectronics fabrication processes, and MEMS fuses for military munitions mass-produced like computer chips.

Figure: This nanoporous copper structure is a precursor material for explosive compounds used in military detonators. The structure can be formed on chips, and then converted into an explosive compound (source: Jason Nadler/GTRI).

Article first published in Nanomaterials News.