The new mixed alcoholato-acetylacetonato precursor Zr(acac) 2 (hfip) 2 , where hfip = OCH(CF 3 ) 2 , has been used to deposit zirconia at temperatures between 350 and 700 C. This compound, a liquid at room temperature, combines a high vapor pressure with a relatively low hydrolysis sensitivity. At 0.5 mbar total pressure, high growth rates of up to 200 nm min ±1 were reached in our cold-wall reactor, the apparent activation energy in the kinetic regime being 81.5 kJ mol ±1 . Zirconia films with C and F levels between 0.25 and 0.50 at.-% were obtained in a temperature window of 475 C to 625 C. The impact of deposition temperature on the microstructure has been followed by both field-emission scanning electron microscopy (SEM) and X-ray diffraction (XRD). With increasing deposition temperature, the initially cubic zirconia films convert progressively into the monoclinic equilibrium phase, probably due to a crystallite size effect.

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The Fused Deposition of Ceramics (FDC) process is an extrusion based layered manufacturing technique. In this study, the microstructural and property homogeneity of GS44-Si3N4 parts made by FDC is examined. The feedstock, green, and sintered parts were examined using characterization techniques such as optical and scanning electron microscopy, x-ray radiography, and x-ray diffraction. In addition, mechanical properties (σf, and Klc), shrinkage, and warpage results were used to characterize the FDC parts. It was found that by using proper build parameters and tool paths, dense, homogenous, near-net-shape GS44-Si3N4 parts can be fabricated. While the mechanical properties of these parts are shown to be isotropic, there is some degree of texturing detected with XRD. Si3N4 filament feedstock intentionally textured with 5.5 vol% of β-seed particles has also been made.

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