Ethanol-Induced Flash Sintering of ZnO Ceramics at Room Temperature

Abstract

Ceramic flash sintering with a strong electric field at room temperature is the most attractive method. This paper presents the flash sintering of ZnO ceramics at room temperature by the application of a 3-kV/cm electric field after a dropwise addition of ethanol. This method is simple and easy to control. The density of the specimen exceeded 96% after 30 s of sintering. No significant difference was observed in the initiation voltage of flash sintering with and without the dropwise addition of ethanol. Ethanol burns upon dropwise addition, causing a discharge to first occur far from the location of the dropwise addition, followed by glowing and heating up, which causes the temperature of the entire specimen to rise.

Rapid low-temperature densification of Ag2Se bulk material: mass transfer through the dissociative adsorption reaction of Ag protrusions and Se saturated vapor

“…This process can achieve full densification of ceramic materials in a very brief period. Building on the potential of this unique electrification process, reports on ultra-high voltage (>1000 V cm −1 ) flash sintering [33][34][35] and liquid phase flash sintering [36][37][38][39] have continued to emerge in recent years. In 2021, Yang et al [40] took advantage of the rapid migration of Zn 2+ under a sawtooth-wave electric field and the dynamic growth of a three-dimensional ionic conduction network, achieving the one-step synthesis and densification of β-Zn 4 Sb 3 .…”

Use of partial discharges measurements and video recordings to investigate the influence of relative humidity on zinc oxide subjected to high electric fields

“…Flash sintering relies on applying an electric field during the heat treatment, in order to reduce significantly sintering temperatures and times [6][7][8]. Successful densification of ZnO was first demonstrated for an electric field applied at relatively high temperature [8][9][10][11][12][13][14] but recent works report that flash sintering of ZnO can also occur at room temperature [15][16][17][18][19]. This property opens up remarkable prospects in terms of energy savings.…”