In-situ synthesis of Y2W3O12 within a Co-based superalloy powder mixture

In this work, the synthesis of the negative thermal expansion ceramic Y2W3O12 within a Co-based superalloy was analyzed in detail. On the basis of thermal analysis of the synthesis from the feedstock powders Y2O3 and WO3 further experiments were conducted. Thermal behavior and stability of different mixtures of the powders Y2O3, WO3 and the Co-based superalloy were investigated. The qualitative and quantitative results of the synthesis separately and within the superalloy are presented as achieved by energy dispersive X-ray analysis, X-ray powder diffraction, differential thermal analysis and thermal gravimetric analysis. It was found that the synthesis of yttrium tungstate inside the Co-based superalloy is possible with a defined temperature program and a simple basic production process of powder mixtures.