Journal of Materials Research


Synthesis of open-cell metal foams by templated directed vapor deposition

Douglas T. Queheillalta1, Derek D. Hassa1, David J. Sypecka1 and Haydn N. G. Wadleya1

a1 Department of Materials Science and Engineering, School of Engineering and Applied Science, University of Virginia, Charlottesville, Virginia 22904


Low-density, open-cell nickel base superalloy foams have been synthesized by a high-rate, electron beam-directed vapor deposition process and their mechanical properties evaluated. The deposition process uses an open-cell polymer foam template upon which is deposited a metal alloy coating. The electron beam evaporated flux was entrained in a rarefied transonic gas jet and propagated along the flow stream lines through the polymer structure. After vapor deposition, the polymer template was removed by low-temperature thermal decomposition. The resultant ultralightweight metal foams consisted of a three-dimensional open cell, reticulated structure possessing hollow triangular ligaments with relative densities of <3%. Their mechanical integrity was increased by either pressureless or transient liquid phase sintering. The mechanical properties of these ultralightweight metal foams were comparable to theoretical predictions for open-cell, reticulated foams.

(Received September 06 2000)

(Accepted January 17 2001)