Abstract: SiC whisker reinforced laminated Si₃N₄/BN ceramics with additives Y₂O₃, Al₂O₃ and MgO were prepared by spark plasma sintering(SPS) in 13min of heating
to 1650℃ and 15min dwell time. The density of the samples densified by SPS was 3.18g/cm³. Bending strength reached 600 MPa, and the work of fracture
reached 3500 J/m². The arrangement of hard Si₃N₄ layer and soft BN layer, the pull-out and broken of SiC whisker were the main reason for improving toughness
of this ceramic. XRD and SEM indicated SiC whisker, long rod like β-Si₃N₄ and platelet like hex-BN were the main phase and SiC whisker, long rod like β-Si₃N₄ had strong preferred orientation.

Key words: SPS, laminated ceramics, Si₃N₄