Selected samples were then heated treated under controlled conditions
to minimize risk of fractures during the elimination/vaporization
of paraffin and other additives (Vitorino et al., 2013). Thus the samples
were fired at 2 °C min−1 fromroomtemperature up to 200 °C, followed
by one isothermal plateau at 200 °C for 3 h, 2 °C min−1 until 500 °C,
5 °C min−1 to the final sintering temperature (1550 °C in the case of
alumina and 1100 °C the other cases), with a plateau of 2 h. Then the
samples were cooled at room temperature at 5 °C min−1