Effect of seed particles content on texture formation of Si3N4 ceramics by gel-casting in a strong magnetic field

• Published in: Advances in manufacturing 2015-09, Vol.3 (3), p.193-201
• Main Authors: Yang, Zhi-Gang, Yu, Jian-Bo, Li, Chuan-Jun, Deng, Kang, Ren, Zhong-Ming, Wang, Qiu-Liang, Dai, Yin-Ming, Wang, Hui
• Format: Article
• Language: English
• Subjects: Casting; Ceramics; Control; Crystals; Engineering; Gelcasting; Hydroxyapatite; Loose powder sintering; Machines; Magnetic fields; Manufacturing; Mechatronics; Nanotechnology and Microengineering; Pressure casting; Processes; Robotics; Silicon nitride; Sintering; Slurries; Stability; Texture
• ISSN: 2095-3127; 2195-3597
• DOI: 10.1007/s40436-015-0106-5

In this paper, the textured Si 3 N 4 ceramics were prepared by adding seed particles during gel-casting in the magnetic field of 6 T, followed by pressureless sintering. The effect of pH on the stability and dispersibility of Si 3 N 4 slurry and the effect of seed particles content on texture formation of Si 3 N 4 ceramics were both studied. Those results showed that the slurry with good stability and dispersibility was obtained when pH was about 11.6. The a or b -axis of Si 3 N 4 particles or crystals was aligned parallel to the direction of the magnetic field in the magnetic field of 6 T. The degree of texture of Si 3 N 4 ceramics further increased during sintering. With the increasing of additional β -Si 3 N 4 particles in the magnetic field of 6 T, the degree of texture increased from 0.19 without seed particles to 0.76 with 9% (mass fraction) seed particles. The increase of seed particles content promoted the texture formation of Si 3 N 4 ceramics.