Experimental research on Al₂O₃/YAG eutectic in site composite with laser remelting

With the melting point above 1800°C and the excellent properties, the alumina-rare earth oxide eutectic in situ composite and its preparation technique have aroused much concern in recent years. This paper reports the experimental research on the eutectic Al₂O₃/YAG in situ ceramic composite and the laser remelting technique. The results show that: (1) The scanning rate and the power density of the laser beam have crucial effect on the laser remelting experiment. With the technical parameters adjusted, the smooth, level and compact remelted layer without macroscopic hole and crack can be obtained. The remelted layer becomes thinner with the increase of scanning rate. (2) The laser remelted Al₂O₃/YAG eutectic in situ ceramic composite is composed of Al₂O₃ and YAG phases with typical lamellar eutectic structure. As the solidification rate is very high, the eutectic spacing is very small.