Fabrication of Spherical Thermal-Conductive Silicon Nitride Powder

Abstract:

In this paper, α-Si₃N₄ was mixed with Y₂O₃ and MgO by ball milling. Spray granulation was adopted to fabricate spherical powder. The influence of the sintering temperature and the holding time on the thermal conductivity of the powder was studied. The results show that α-Si₃N₄ raw powder was transformed into β-phase after sintering. Spherical powder, of which the diameter is about 20 μm, was fabricated. Some compounds such as YMgSi₂O₅N, Y₄Si₂N₂O₇ and Y₂Si₃N₄O₃ were generated in the samples. The thermal conductivity of the pressed powder first increased then decreased with the sintering temperature rising, showing a maximum at 1800°C. Also the thermal conductivity first increased then decreased as the holding time getting longer, showing a maximum at a sintering time of 2 hours.

• Periodical: Advanced Materials Research (Volume 412)
• Pages: 175-178
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.412.175
• Online since: November 2011
• Authors: Nan Zhong, Xiao Shan Ning, Ke Xin Chen, Meng Meng Peng
• Keywords: High Thermal Conductivity, Spherical Powder, β-Si₃N₄

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