Recently, porous metals and ceramics have been made by a novel solid-gas eutectic solidifica- tion process (the GASAR process). Control of the direction and rate of cooling and of the pressure of the system allows the control of the size, shape, orientation and volume fraction of the pores. Here we describe the microstructure and uniaxial tensile behaviour of porous copper made by the GASAR process. The strength of the porous specimens decreases linearly with increasing porosity, as expected for a material with aligned cylindrical pores. The yield strength of the nominally solid specimens is lower than that of the low porosity specimens; this strength anomaly is explained in terms of the degree of constraint on the grains. Finally, the potential for increased mechanical efficiency of materials made by the GASAR process is described.
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