Texturing of Si₃N₄ ceramics via strong magnetic field alignment

This paper reports the texture development in Si₃N₄ by strong magnetic field alignment (SMFA), using slip casting of α-Si ₃N₄ raw powder (SN-E10) and pressureless sintering. The texture of β-Si₃N₄ in the green and sintered bodies was characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The a, b-axis and c-axis aligned β-Si₃N ₄ has been obtained by the static and rotating magnetic field of 12 T, respectively. The β-seed addition and prolonged sintering both enhance the texture, but the former is more efficient. This work suggests an efficient SMFA strategy of producing highly textured β-Si₃N₄, particularly the unidirectionally c-axis aligned β-Si₃N ₄ by seeding the α-raw powder using the less-agglomerated β-phase particles.