A novel strategy for c-axis textured silicon nitride ceramics by hot extrusion

•Highly c-axis textured β-silicon nitride (β-Si3N4) ceramics without seeding was prepared by a new method of hot extrusion using spark plasma heating at 1800 °C in 10 min.•The (002) pole figure showed a characteristic of center rotational symmetry and an average cline angle between hot extruding direction and [00l] direction of β-Si3N4 grains as low as 8.7°.•Higher hardness was achieved mainly due to the finer grain size compared to that of c-axis textured Si3N4 ceramics with seeding.