Development of Silicon Nitride Based Matrices

A feasible way to produce SiC long fibre reinforced Si3N4 is by vacuum infiltration of Si3N4 slurry followed by reaction bonding of the matrix. To minimize degradation of the fibres the nitridation reaction has to take place at moderate temperatures. In the present work a number of Si3N4-matrices processed by a modified RBSN technique and mixed with ZrO2-additives to optimize the nitridation cycle will be discussed. The results show that ZrO2 has a remarkably accelerating effect on the nitridation. It is thus possible to decrease the exposure of SiC fibres to high temperatures.