ISSN:
1551-2916
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Tungsten bronze Sr2−xCaxNaNb5O15 (SCNN, x= 0.1) piezoelectric ceramics were prepared by a novel super-fast sintering technique, i.e., spark plasma sintering (SPS). Sintering was conducted at temperatures ranging from 1000° to 1200°C under vacuum under 35 MPa. The heating rate varied from 30° to 300°C/min and the soaking time was in the range of 5 to 60 min. The microstructure and the phase identification were analyzed via scanning electron microscopy (SEM) and X-ray diffraction (XRD). The density of the sintered ceramics increased with an increase in sintering temperature as well as in heating rate. Materials with a near-theoretical density could be attained by sintering at 1200°C for 5 min with a heating rate of 300°C/min, exhibiting a homogeneous and fine-grained microstructure (grain size about 2.7 μm) and a uniform translucency. A tetragonal tungsten bronze phase was identified in ceramics sintered at temperatures above 1200°C, whereas the tungsten bronze phase transformed to a SrNb2O6-type phase in the materials sintered at temperatures below 1200°C. XRD patterns demonstrated a preferred crystallographic orientation of the SCNN grains with their c-axes perpendicular to the pressing direction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1151-2916.2002.tb00520.x
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