Abstract
A powder spray stacking apparatus has been developed for fine stacking of mixed powders. Functionally gradient material has been successfully fabricated using this process, which has fine microstructural transition from stainless steel to zirconia ceramics.
Mixing ratio of metal and ceramic powders in the suspension using ethanol as a solvent was varied gradually by the computer control. Deposited products, which were prepared by spraying and depositing the suspension on preheated substrates, were CIP'ed, encapsulated and HIP'ed. Detailed observation of the microstructure has revealed that this process could precisely control the various composition profile with the minimum control size of 0.01mm. It has been shown that the thermal shock resistance of spray formed FGM'was significantly higher than that of monolithic zirconia ceramics.
