Microwave Sintering Modification of 85M₇Z₃CLT Microwave Dielectric Ceramics

Abstract:

The 0.85(Mg_0.7Zn_0.3)TiO₃-0.15(Ca_0.61La_0.26)TiO₃(referred to as 85M₇Z₃CLT) ceramics were fabricated by microwave sintering(MWS) and conventional sintering(CS) techniques. The effects of MWS and CS on the sintering property, crystal phase structure and dielectric properties of 85M₇Z₃CLT were discussed. Compared with CS, MWS had a short sintering period and a high volume density. The results indicated that the phase composition of 85M₇Z₃CLT ceramics were not changed after MWS, with (Mg_0.7Zn_0.3)TiO₃ and (Ca_0.61La_0.26)TiO₃ structure as the main crystal phase were also obtained by MWS. However, the grain growth was significantly inhibited due to the rapid sintering speed of MWS, which resulted in a fine, uniform microstructure. Furthermore, microwave-sintered ceramics had excellent dielectric properties due to the miscellaneous phase (Mg_0.7Zn_0.3)Ti₂O₅ being suppressed. As a result, excellent dielectric properties of 27.11 for ε_r, 103,500GHz for Q·f and +2ppm/°C for τ_f were obtained by microwave sintering at 1275°C for 20 min. Therefore, the ceramic quality factor was increased by 22% compared with the conventional sintering.Key words: microwave technique; (Mg,Zn)TiO₃; dielectric ceramics

• Periodical: Materials Science Forum (Volume 1147)
• Pages: 13-19
• DOI: https://doi.org/10.4028/p-oM3LbF
• Online since: March 2025
• Authors: Li Zhao*, Guang Yu Li, Jia Feng Liu, Xun Fei Cai, Qi Hu, Yu Ye Hu, Ya Long Jiang
• Keywords: (Mg,Zn)TiO₃, Dielectric Ceramics, Dielectric Property, Microwave Dielectric Ceramics, Microwave Sintering

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