The kinetics of hot-pressing for undoped and donor-doped BaTiO <Subscript>3 </Subscript> ceramics
نویسندگان
چکیده
The kinetics of hot-pressing for undoped and donor-doped BaTiO3 of high purity have been studied at 1050~ and at 2.3 to 27.6 MPa in an oxidizing atmosphere. The stress exponent and grain size exponent of the densification rate are indicative of control of densification by a grain boundary diffusion mechanism. The activation enthalpy (,~ 400 kJ mo1-1 ) for the densification process has been measured over the range of 1050 to 1200 ~ No significant influence of the donor is observed on the densification of BaTiO3 until the late stages of sintering.
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