Grain growth for CuO-BaO mixtures added BaTi{sub 1+x}O{sub 3+2x} ceramics
- Chinese Air Force Academy, Kaohsiung (Taiwan, Province of China). Dept. of Electronic Engineering
CuO-BaO mixtures (molar ratio, CuO/BaO = 1, 2, 2.5) at the 1 wt% level were added to BaTi{sub 1+x}O{sub 3+2x} ({minus}0.01 {le} x {le} 0.02) ceramics as a liquid phase promoter to investigate the grain growth of BaTi{sub 1+x}O{sub 3+2x} ceramics. Sintering in air for 2 h at 950 to 1,250 C was investigated to study the densification process, whereas sintering in air for 1 to 16 h at 1,150 to 1,250 C was investigated to study the grain growth. The sintered grain morphologies of BaTi{sub 1+x}O{sub 3+2x} ceramics depend on the TiO{sub 2}/BaO ratio, the sintering temperature and time, and the CuO/BaO ratio, slightly. The average grain size increased with the sintering time and temperature. Grain growth is discussed in terms of the kinetic growth equation: G{sup n} {minus} G{sub o}{sup n} = K{sub o} t exp({minus}Q/RT). It was found that the preexponential, the grain growth exponents, and the activation energies of the BaTi{sub 1+x}O{sub 3+2x} system are all dependent on the CuO/BaO ratio, the sintering temperature, and the TiO{sub 2}/BaO ratio. In the BaTi{sub 1+x}O{sub 3+2x}/CuO-BaO system, the average n values are in the range of 4.1 to 7.6, and the activation energies are in the range of 109 {+-} 30 to 1,007 {+-} 180.
- OSTI ID:
- 586018
- Journal Information:
- Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 12 Vol. 32; ISSN MRBUAC; ISSN 0025-5408
- Country of Publication:
- United States
- Language:
- English
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