Cold Sintering of Na2WO4 Ceramics using a Na2WO4-2H2O Chemistry

Hao，Jianyu1; Guo，Jing1; Ma，Chuansheng1; Yao，Fang Zhou1; Yao，Bin1; Si，Mingming1; Zhao，Enda1; Wang，Hong1,2

2021

10.1016/j.jeurceramsoc.2021.05.019

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY   影响因子和分区

0955-2219

1873-619X

Crystal water is a kind of water molecules that are incorporated into the crystal structure of hydrated salts, which are generally decomposed at very low temperatures (usually 100∼200 °C). NaWO is a compound that could react with HO forming the NaWO·2HO hydrated crystal salt under certain conditions. In this work, the cold sintering of NaWO ceramics is studied using a NaWO-2HO chemistry at a low sintering temperature of 120 °C. Their sintering mechanism has been investigated using SEM, TEM, DSC, FTIR, together with the shrinkage rates of the samples. During the sintering process, the intentionally added liquid water reacts with NaWO powders to produce a NaWO·2HO and NaWO composite, and the crystal water can be decomposed from the NaWO·2HO phase under a certain sintering condition. The water in both liquid and solid forms contributes to the densification of NaWO ceramics. Finally, dense NaWO ceramics with excellent properties (permittivity: 5.7; Q × f: 70 000 GHz; TCF: −70 ppm/°C) have been obtained by removing the residual water after a heat treatment. Such sintering process can be generalized to the densification of other inorganic materials that easily react with liquid water to form hydrated salts, which provides a strategy for the cold sintering with crystal water.

Cold sintering process Hydrated flux Hydrated salt Microwave dielectrics Na2WO4 Sintering mechanism

SCI ; EI

英语

通讯

WOS:000661246900002

20212110402103

MATERIALS SCIENCE

2-s2.0-85106268710

Scopus

1.State Key Laboratory for Mechanical Behavior of Materials & School of Electronic and Information Engineering,Xi'an Jiaotong University,Xi'an,710049,China
2.Department of Materials Science and Engineering & Shenzhen Engineering Research Center for Novel Electronic Information Materials and Devices,Southern University of Science and Technology,Shenzhen,518055,China

Hao，Jianyu,Guo，Jing,Ma，Chuansheng,et al. Cold Sintering of Na2WO4 Ceramics using a Na2WO4-2H2O Chemistry[J]. JOURNAL OF THE EUROPEAN CERAMIC SOCIETY,2021,41:6029-6034.

Hao，Jianyu.,Guo，Jing.,Ma，Chuansheng.,Yao，Fang Zhou.,Yao，Bin.,...&Wang，Hong.(2021).Cold Sintering of Na2WO4 Ceramics using a Na2WO4-2H2O Chemistry.JOURNAL OF THE EUROPEAN CERAMIC SOCIETY,41,6029-6034.

Hao，Jianyu,et al."Cold Sintering of Na2WO4 Ceramics using a Na2WO4-2H2O Chemistry".JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 41(2021):6029-6034.