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Adding plasticizer is an efficient way to regulate the rheological behavior of ceramic paste and quality of green body in stereolithography-based additive manufacturing. The type and content of plasticizers (polyethylene glycol (PEG) and dibutyl phthalate (DBP)) had substantial effects on the rheological behavior and solid loading of ceramic paste, leading to varied macro / micro structure and strength of the green and sintered parts. DBP significantly reduced the viscosity and increased solid loading, and could adjust the flexibility of the green body by reducing the crosslinking density of UV curing system. PEG could inhibit crack initiation to some extent, but it was less effective for preventing cracking than DBP on ceramic parts with large-sized cross sections. It was concluded that DBP was more suitable as a plasticizer in alumina paste for SL additive manufacturing to form dense parts without defects. [ABSTRACT FROM AUTHOR]

The mechanical property of advanced ceramics by additive manufacturing through layer‐by‐layer processing and subsequent sintering has been employed as a key basis for optimizing the processing and developing future application. 3Y‐TZP ceramic was fabricated by stereolithography‐based additive manufacturing, and the mechanical properties were investigated by nanoindentation and microscratch testing. The microscopic mechanism and evolution of surface deformation and damage induced by scratching were revealed by scanning electron microscopy and surface interferometer. Results showed that the nanoindentation hardness and elastic modulus were comparable to those of conventional process. With the increase in the applied normal load, the scratch‐induced damage followed three sequential stages, that is, plastic plowing, microcracking and surface spalling. The magnitude of the microcracks nucleated during scratching depended on the applied normal load. Concerning the homogeneity and integrity with the sintered parts without delaminated cracks and pores, the evolution of surface damage was discussed in different stages. It was concluded that the layer‐by‐layer process did not affect the characteristic of microcracking evolution. [ABSTRACT FROM AUTHOR]

The nanoscale plasticity phenomena in zirconia-toughened alumina (ZTA) ceramics with yttria-stabilized zirconia (YSZ) addition of 10% and 30% fabricated by additive manufacturing based on a stereolithography technique were explored in detail by nanoindentation and scanning electron microscopy. It was demonstrated that the initiation of nanoscale plasticity was attributed to the combined contributions from the generation of nanoscale shear deformation bands and localized microcracking at the indentations. Such localized plastic behavior underneath the nanoindenter was interpreted by maximum shear stress analysis. The response of the phase boundary during indentation was emphasized through crack propagation paths, and optimization of alumina–YSZ adaptation through component design and SL processing was expected. [ABSTRACT FROM AUTHOR]