Microstructure and properties of ZnO-Bi2O3-based varistor ceramics via flash sintering

Purpose This paper aims to study the effects of MnO2 on the ZnO–Bi2O3-based varistor prepared via flash sintering (FS) Design/methodology/approach MnO2-doped ZnO–Bi2O3-based varistors were successfully prepared by the FS with a step-wise increase of the .current in 60 s at the furnace temperature <750°C under the direct current electric field of 300 V cm−1. The FS process, microstructure and the electrical performance of ZnO–Bi2O3-based varistors were systematically investigated. Findings The doping of MnO2 significantly decreased the onset temperature of FS and improved the electrical performance of FS ZnO varistor ceramic. The sample with 0.5 mol% MnO2 doping shows the highest improvement, with the nonlinear coefficient of 18, the leakage current of 16.82 µA, the threshold voltage of 459 V/mm and the dielectric constant of 1,221 at 1 kHz. Originality/value FS is a wonderful technology to enhance ZnO varistors for its low energy consumption, and a short sintering time can reduce grain growth and inhabit Bi2O3 volatilize, yet few research studies work on that. In this research, the authors analyzed the FS process and improved the electrical characteristics through MnO2 doping.

[1]  Zhengfeng Wang,et al.  Compositional modulation in ZnGa2O4 via Zn2+/Ge4+ co-doping to simultaneously lower sintering temperature and improve microwave dielectric properties , 2021, Journal of Advanced Ceramics.

[2]  Kongfa Chen,et al.  Electronic structure and enhanced photoelectrocatalytic performance of RuxZn1−xO/Ti electrodes , 2021, Journal of Advanced Ceramics.

[3]  Anze Shui,et al.  Enhanced electromagnetic wave absorption property of binary ZnO/NiCo2O4 composites , 2021, Journal of Advanced Ceramics.

[4]  K. Rybakov,et al.  Rapid microwave sintering of zinc oxide-based varistor ceramics , 2021 .

[5]  Lijun Yang,et al.  Enhanced electrical properties of ZnO varistor ceramics by spark plasma sintering: Role of annealing , 2020 .

[6]  Dong Xu,et al.  Fabrication and electrical characteristics of flash-sintered SiO2-doped ZnO-Bi2O3-MnO2 varistors , 2020, Journal of Advanced Ceramics.

[7]  A. Kulkarni,et al.  Influence of CaO doping on phase, microstructure, electrical and dielectric properties of ZnO varistors , 2020 .

[8]  Dong Xu,et al.  Enhancement of dielectric and non-ohmic properties of graded Co doped CaCu3Ti4O12 thin films , 2020 .

[9]  X. Li,et al.  Alternating current field flash sintering 99% relative density ZnO ceramics at room temperature , 2020 .

[10]  X. Su,et al.  Dense Na0.5K0.5NbO3 ceramics produced by reactive flash sintering of NaNbO3-KNbO3 mixed powders , 2020 .

[11]  Zhenjun Wang,et al.  Flash sintering of 3YSZ/Al 2 O 3 ‐platelet composites , 2020 .

[12]  Zhenjun Wang,et al.  Fabrication of lead zirconate titanate ceramics by reaction flash sintering of PbO-ZrO2-TiO2 mixed oxides , 2019, Journal of the European Ceramic Society.

[13]  Yiguang Wang,et al.  Microstructure and dielectric property of flash sintered SiO2-coated BaTiO3 ceramics , 2019, Scripta Materialia.

[14]  Dong Xu,et al.  Improved dielectric and non-ohmic properties of (Zn + Zr) codoped CaCu3Ti4O12 thin films , 2019, Ceramics International.

[15]  Jian Luo,et al.  Flash Sintering Activated by Bulk Phase and Grain Boundary Complexion Transformations , 2019 .

[16]  Dong Xu,et al.  Enhanced dielectric properties and electrical responses of cobalt-doped CaCu3Ti4O12 thin films , 2019, Journal of Alloys and Compounds.

[17]  T. Tsakalakos,et al.  Flash Sintering using Controlled Current Ramp , 2018, Journal of the European Ceramic Society.

[18]  Jian Luo,et al.  Water-assisted flash sintering: Flashing ZnO at room temperature to achieve ~ 98% density in seconds , 2018 .

[19]  Jian Luo,et al.  Two-step flash sintering of ZnO: Fast densification with suppressed grain growth , 2017 .

[20]  Jian Luo,et al.  Probing the densification mechanisms during flash sintering of ZnO , 2017 .

[21]  C. Randall,et al.  Demonstration of the cold sintering process study for the densification and grain growth of ZnO ceramics , 2017 .

[22]  K. Rady,et al.  Study of the effect of substitution by MnO2 and V2O5 on the microstructure, electrical and dielectric characteristics of zinc oxide ceramics , 2016 .

[23]  R. Raj.  Analysis of the Power Density at the Onset of Flash Sintering , 2016 .

[24]  R. Raj,et al.  Electroluminescence and the measurement of temperature during Stage III of flash sintering experiments , 2015 .

[25]  C. Carry,et al.  Flash sintering incubation in Al2O3/TZP composites , 2015 .

[26]  Jian Luo,et al.  Promoting the flash sintering of ZnO in reduced atmospheres to achieve nearly full densities at furnace temperatures of <120 °C , 2015 .

[27]  Dong Xu,et al.  Dielectric and varistor properties of Cu doped Li0.02Ni0.98O ceramics , 2015, Journal of Materials Science: Materials in Electronics.

[28]  R. S. Bonilla,et al.  Electrical characteristics of flash sintering: thermal runaway of Joule heating , 2015 .

[29]  Shengtao Li,et al.  Advances in ZnO–Bi2O3 based varistors , 2015, Journal of Materials Science: Materials in Electronics.

[30]  E. Muccillo,et al.  Electric field-assisted sintering of tin dioxide with manganese dioxide addition , 2014 .

[31]  Guorong Li,et al.  Influence of Cr2O3 on ZnO–Bi2O3–MnO2-based varistor ceramics , 2014 .

[32]  V. Sglavo,et al.  Densification of La0.6Sr0.4Co0.2Fe0.8O3 ceramic by flash sintering at temperature less than 100 °C , 2014, Journal of Materials Science.

[33]  O. Guillon,et al.  Flash Sintering of Nanocrystalline Zinc Oxide and its Influence on Microstructure and Defect Formation , 2014 .

[34]  E. Muccillo,et al.  Electric field-assisted flash sintering of tin dioxide , 2014 .

[35]  R. Raj,et al.  The Effect of Electric Field on Sintering and Electrical Conductivity of Titania , 2014 .

[36]  S. Bonilla,et al.  Preliminary investigation of flash sintering of SiC , 2013 .

[37]  R. Raj,et al.  Influence of the Field and the Current Limit on Flash Sintering at Isothermal Furnace Temperatures , 2013 .

[38]  Dong Xu,et al.  Highly nonlinear property and threshold voltage of Sc2O3 doped ZnO-Bi2O3-based varistor ceramics , 2013 .

[39]  R. Raj.  Joule heating during flash-sintering , 2012 .

[40]  Zhenhua Wang,et al.  A novel sintering method to obtain fully dense gadolinia doped ceria by applying a direct current , 2012 .

[41]  N. Daneu,et al.  Microstructural engineering of ZnO-based varistor ceramics , 2012, Journal of Materials Science.

[42]  M. Cologna,et al.  Influence of Externally Imposed and Internally Generated Electrical Fields on Grain Growth, Diffusional Creep, Sintering and Related Phenomena in Ceramics , 2011 .

[43]  M. Cologna,et al.  Flash Sintering of Nanograin Zirconia in <5 s at 850°C , 2010 .

[44]  Dong Xu,et al.  Microstructure and electrical properties of ZnO–Bi2O3-based varistor ceramics by different sintering processes , 2009 .

[45]  C. Nahm.  Effect of MnO2 addition on microstructure and electrical properties of ZnO–V2O5-based varistor ceramics , 2009 .

[46]  Blatter,et al.  Carrier transport through grain boundaries in semiconductors. , 1986, Physical review. B, Condensed matter.

[47]  S. R. Kurtz,et al.  Electroluminescence in ZnO varistors: Evidence for hole contributions to the breakdown mechanism , 1985 .