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This paper explores the templated grain growth and texturing of Pb(Yb1/2Nb1/2)O3‐Pb(Mg1/3Nb2/3)O3‐PbTiO3 (PYN‐PMN‐PT) ceramics. A PbO‐CuO liquid phase was determined to substantially increase the growth of PYN‐PMN‐PT on barium titanate template particles. Texturing resulted in an 83% enhancement in strain behavior (754 pm/V) compared with random PYN‐PMN‐PT ceramics (413 pm/V). The increased Pb(Yb1/2Nb1/2)O3 (PYN) content of textured 21PYN‐41PMN‐38PT resulted in a high coercive field of 13.9 kV/cm. Residual barium titanate templates reduced the polarization from 33.7 to 26.2 µC/cm2 and slightly decreased the Curie temperature (236‐224°C). These results show that textured PYN‐PMN‐PT is a promising material for high strain and coercive field transducers. [ABSTRACT FROM AUTHOR]

This study explores sintering and piezoelectricity of ZnO‐doped perovskite Pb(In1/2Nb1/2)O3‐Pb(Zn1/3Nb2/3)O3‐PbTiO3 (PIN‐PZN‐PT) ceramics. The enhanced densification of ZnO‐doped PIN‐PZN‐PT is attributed to the formation of oxygen vacancies by the incorporation of Zn2+ into the perovskite B‐site and increased rate of bulk diffusion relative to undoped PIN‐PZN‐PT. Incorporation of Zn2+ into the perovskite lattice increased the tetragonal character of PIN‐PZN‐PT as demonstrated by tetragonal peak splitting and increased Curie temperature. Sintering in flowing oxygen reduced the solubility of Zn2+ in the perovskite lattice and resulted in rhombohedral PIN‐PZN‐PT. Sintering in oxygen prevented secondary phase formation which resulted in a high‐piezoelectric coefficient (d33 – 550 pC/N), high‐coercive field (Ec – 13 kV/cm), and high‐rhombohedral to tetragonal phase transition temperature (Tr‐t – 165°C). We conclude that ZnO‐doped PIN‐PZN‐PT ceramics are excellent candidates for high‐power transducer applications. [ABSTRACT FROM AUTHOR]

This paper describes a sintering technique for ceramics and ceramic-based composites, using water as a transient solvent to effect densification (i.e. sintering) at temperatures between room temperature and 200 °C. To emphasize the incredible reduction in sintering temperature relative to conventional thermal sintering this new approach is named the 'Cold Sintering Process' (CSP). Basically CSP uses a transient aqueous environment to effect densification by a mediated dissolution-precipitation process. CSP of NaCl, alkali molybdates and V2O5 with small concentrations of water are described in detail, but the process is extended and demonstrated for a diverse range of chemistries (oxides, carbonates, bromides, fluorides, chlorides and phosphates), multiple crystal structures, and multimaterial applications. Furthermore, the properties of selected CSP samples are demonstrated to be essentially equivalent as samples made by conventional thermal sintering. [ABSTRACT FROM AUTHOR]

B2O3-SiO2 is shown to act as a transient liquid phase sintering aid that reduces the sintering temperature of Nd:YAG ceramics to 1600 °C. 1 at.% Nd3xY3-3xAl5O12 (Nd:YAG) ceramics were doped with 0.34-1.35 mol% B2O3-SiO2 and sintered between 1100 and 1700 °C. Dilatometric measurements show that B2O3-SiO2 doping increases the densification rate during intermediate-stage sintering relative to SiO2-doped samples. B3+ content is reduced to <5 ppm in samples heated to 1500 °C, as determined by mass spectrometry. For B2O3-SiO2-doped samples, final stage densification and grain growth follow a more densifying sintering trajectory than SiO2-doped 1 at.% Nd:YAG ceramics because there is less SiO2 during final-stage densification. The increased densification kinetics during intermediate-stage sintering lead to highly transparent Nd:YAG ceramics when sintered at 1600 °C in either vacuum or oxygen. Thus, transparent Nd: YAG ceramics can be sintered without the need for expensive refractory metal vacuum furnaces or pressure-assisted densification. [ABSTRACT FROM AUTHOR]

A new sintering technique (cold sintering) for ceramics and ceramic-based composites using water as a transient solvent to effect densification at temperatures between room temperature and 200 °C is described. [ABSTRACT FROM AUTHOR]