Fabrication of porous copper by unidirectional solidification under hydrogen and its properties

Lotus-structured porous copper was fabricated by unidirectional solidificat ion in the mixture gas of hydrogen and argon at the high pressure up to 2 M Pa. The pore size and porosity were controlled by the melting temperature a nd the mixture ratio and pressure of the gases, while the pore growth direc tion was controlled by the freezing direction. The pore diameter ranges fro m 5 mum to 5 mm and maximum porosity is about 70%. The porous copper with a ligned long pores displays superior mechanical properties, which is differe nt from conventional porous materials with random pores such as sintered ma terials, foamed materials, cell-structured materials etc. In this paper the fabrication and the result of the mechanical property and the internal fri ction measurement are described. (C) 2001 Elsevier Science B.V. All rights reserved.