2006 Volume 47 Issue 9 Pages 2248-2253
Lotus-type porous metals, whose pores are aligned in one direction by unidirectional solidification, have a unique combination of properties. These are expected as innovative engineering materials with anisotropy of the properties. A reliable joining technology such as welding is required for the industrial application of the lotus-type porous metals as well as processing technology. We have already investigated the melting property of the lotus-type porous copper and magnesium by laser beam irradiation and have pointed out that these materials possessed anisotropy of melting property with the pore direction perpendicular and parallel to the specimen surface, especially remarkable anisotropy was obtained for the lotus-type porous copper owing to the difference of the laser energy absorption to the specimen surface. In this study, three-dimensional finite element calculations of temperature distribution for the lotus-type porous copper as well as the lotus-type porous magnesium under the non-steady-state conditions were performed in order to investigate the effect of the anisotropy of the laser energy absorption comparing with the anisotropy of thermal conductivity inherent to lotus type porous metals. The effect of these factors on the profile of fusion zone by comparing the results of numerical simulation and the experimental observations were discussed.
