Preparation of zirconium carbide foam by direct foaming method

Ultra light, highly porous, closed-cell structured ZrC foam can be produced in two steps. First, pre-ceramic foam is prepared by direct foaming of zirconia sol and phenolic resin. In the next step, the foamed green body is converted into ZrC foam after carbothermal reduction at 1600 degrees C under argon atmosphere. The obtained ZrC foam has porosity of 85% and possesses uniform cells with an average size of about 40 mu m. The foam also displays excellent thermal stability up to 2400 degrees C. Its compressive strength and thermal conductivity at room temperature are 0.4 MPa and 0.94 W/(m K), respectively. (C) 2014 Elsevier Ltd. All rights reserved.