Development of an instrumented and automated flash sintering setup for enhanced process monitoring and parameter control

Microstructural evolution of 3YSZ flash‐sintered with current ramp control

“…The electrical parameters of the FS, for example, the electric field and electric current density, can significantly affect the characteristics of the sintered material . At certain values of these parameters, the grain size distribution in the sample may be heterogeneous …”

“…Some authors believe that it may be possible to avoid heterogeneous microstructure in flash‐sintered (FSed) materials by gradually increasing the electric current in FS using a current ramp (CRFS). The abrupt increase in the current observed in conventional FS may be related to the thermal gradient in the samples during the flash phenomenon and cause the grain size heterogeneity between the core and surface …”

“…The use of CRFS in sintering of 3 mol% yttria‐stabilized zirconia (3YSZ) has resulted in microstructural homogeneity in experiments using a DC electric field (dog‐bone‐shaped samples) and a preliminary study of AC electric field (cylindrical samples) . Other studies have shown that CRFS increased the densification of zinc oxide samples compared with that obtained by FS …”

“…[1][2][3][4][5] The electrical parameters of the FS, for example, the electric field and electric current density, can significantly affect the characteristics of the sintered material. [5][6][7][8][9][10][11] At certain values of these parameters, the grain size distribution in the sample may be heterogeneous. 10,[12][13][14] The grain size heterogeneity has been attributed due to several reasons: a gradient of temperature on the sample due to heat transfer mechanisms during FS 12,15,16 ; the electric current preferential path forming hotspots, resulting in localized enhancement of grain growth 13,14,17,18 ; difference on grain growth kinetics between the cathode and anode vicinities.…”

“…[5][6][7][8][9][10][11] At certain values of these parameters, the grain size distribution in the sample may be heterogeneous. 10,[12][13][14] The grain size heterogeneity has been attributed due to several reasons: a gradient of temperature on the sample due to heat transfer mechanisms during FS 12,15,16 ; the electric current preferential path forming hotspots, resulting in localized enhancement of grain growth 13,14,17,18 ; difference on grain growth kinetics between the cathode and anode vicinities. 19,20 The properties of materials are related to their microstructure; therefore, knowledge of the grain growth kinetics associated with different FS parameters is essential.…”