Electric field - Flash temperature relationship in liquid-film assisted flash sintering of ceramic nanoparticles

摘要

The balance between heat gain and loss rates is used to establish the relationship between the critical electric field and the onset flash temperature during flash sintering in percolating ceramic nanoparticle compacts. The model assumes particle surface melting at the particle contacts due to local Joule heating. The threshold for electric current percolation through the liquid-film is reached at the flash event. Experimental results of different oxides from the literature are in excellent agreement with the present model. The electric conductivities calculated for the percolating melt fraction at the flash conditions are in good agreement with the melt literature data. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.