Journal of Advanced Ceramics

, Volume 7, Issue 2, pp 152–159 | Cite as

Study of 0.9Al2O3–0.1TiO2 ceramics prepared by a novel DCC-HVCI method

  • Jia-Min Wu
  • Huan Xiao
  • Meng-Yue Liu
  • Ying Chen
  • Yi-Xin Ma
  • Li-Jin Cheng
  • Yu-Sheng Shi
Open Access
Research Article


In this paper, in-situ coagulation of 0.9Al2O3–0.1TiO2 suspension and microwave dielectric properties of 0.9Al2O3–0.1TiO2 ceramics prepared by a novel direct coagulation casting via high valence counter ions (DCC-HVCI) method were proposed. The 0.9Al2O3–0.1TiO2 suspension could be coagulated via controlled release of calcium ions from calcium iodate at an elevated temperature. The influence of tri-ammonium citrate (TAC) content, solid loading, and calcium iodate content on the rheological properties of the suspension was investigated. In addition, the influence of coagulation temperature on coagulation time and properties of green bodies was also studied. It was found that the stable 0.9Al2O3–0.1TiO2 suspension could be successfully prepared by adding 0.3 wt% TAC and adjusting pH value to 10–12 at room temperature. 0.9Al2O3–0.1TiO2 green bodies with uniform microstructures were coagulated by adding 8.0 g/L calcium iodate after treating at 70 °C for 1 h. 0.9Al2O3–0.1TiO2 ceramics, sintered at 1500 for 4 h and annealed at 1100°C for 5 h, showed °Cuniform microstructures with density of 3.62±0.02 g/cm3. The microwave dielectric properties of 0.9Al2O3–0.1TiO2 ceramics prepared by DCC-HVCI method were: εr = 11.26±0.06, Q×f = 11569±629 GHz, τ f = 0.93±0.60 ppm/°C. The DCC-HVCI method is a novel and promising route without binder removal process to prepare complex-shaped microwave dielectric ceramics with uniform microstructures and good microwave dielectric properties.


rheological properties microwave dielectric properties 0.9Al2O3–0.1TiO2 DCC-HVCI 



Our research work presented in this paper was supported by National Natural Science Foundation of China (No. 51501066), China Postdoctoral Science Foundation (Nos. 2015M572136, 2017T100550, and 2016M602290), and the Fundamental Research Funds for the Central University (No. 2017JYCXJJ002). The authors are grateful for the State Key Laboratory of Materials Processing and Die & Mould Technology for mechanical property tests, as well as the Analysis and Testing Center of Huazhong University of Science and Technology for XRD and SEM tests.


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© The Author(s) 2018

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Authors and Affiliations

  1. 1.State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanChina

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