Abstract
A direct selective laser sintering (SLS) process was combined with a laser preheating procedure to decrease the temperature gradient and thermal stress, which was demonstrated as a promising approach for additive manufacturing of BaTiO3 ceramics. The phase compositions in BaTiO3 ceramics fabricated by SLS were investigated by X-ray and neutron diffractions. The surface morphologies and cross-section microstructures were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). A dense hexagonal h-BaTiO3 layer was formed on the surface and extended to a depth of 500 μm, with a relative density higher than 97% and absence of pores or microcracks. SLS resulted in the formation of the high-temperature phase, h-BaTiO3, which was retained at room temperature possibly due to the high cooling rate. The grain boundaries of SLSed h-BaTiO3 ceramics consist of a Ti-rich secondary phase. Compared with that of the pressureless sintered t-BaTiO3 ceramics, the Vickers hardness of SLSed h-BaTiO3 is 70% higher.
Original language | English (US) |
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Pages (from-to) | 1271-1280 |
Number of pages | 10 |
Journal | Journal of the American Ceramic Society |
Volume | 104 |
Issue number | 3 |
DOIs | |
State | Published - Mar 2021 |
Keywords
- additive manufacturing
- barium titanate
- selective laser sintering
ASJC Scopus subject areas
- Ceramics and Composites
- Materials Chemistry