Textured boride/silicon nitride composite ceramic as well as preparation method and application thereof

The invention belongs to the technical field of non-oxide-based ceramics, and discloses a textured boride/silicon nitride composite ceramic as well as a preparation method and application thereof. The composite ceramic is prepared by the following steps: carrying out ball milling on alpha-Si3N4 powder, a sintering aid MgO-Re2O3 and a transition metal boride to obtain mixed powder, heating the mixed powder to 1450-1550 DEG C in an argon atmosphere, carrying out heat preservation, axially pressurizing to 10-50 MPa in the heat preservation process, and carrying out spark plasma sintering to obtain a green body; and carrying out spark plasma sintering on the green body at 1550-1650 DEG C in an argon atmosphere. The low-temperature twice spark plasma sintering is adopted, and the transition metal boride is introduced into the silicon nitride ceramic, so that compared with the traditional textured silicon nitride ceramic prepared at high temperature, the hardness of the textured silicon nitride ceramic is improved