Toughening in boron nitride nanotubes/silicon nitride composites

Boron nitride nanotubes (BNNTs)/silicon nitride composites were fabricated by hot pressing. The fracture toughness of the composite containing 1.5 wt% BNNTs increases about 40% than that of the monolithic. The BNNTs pullout, BNNTs necking and the development of elongated grains are the main responsible factors for the toughness improvement.