New discoveries in the growth of SiC whiskers derived from hydrogen silicone oil

• Published in: Journal of crystal growth 2020-08, Vol.543, p.125711, Article 125711
• Main Authors: Mi, Yueshan, Chen, Yang, Zheng, Zhanshen, Qiao, Ning, Liang, Yuqi
• Format: Article
• Language: English
• Subjects: Atomic diffusion; Carbon; Catalysts; H-PSO; Heat treatment; Morphology; Non-heat treatment factor; Oxide coatings; Partial pressure; Particle size; Prisms; Raw materials; SiC whiskers; Silicon carbide; Silicon oxides; Silicone resins
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2020.125711

•Powder size and carbon matrix worked togetherto influence growth of SiC whiskers.•Hexagonal prism whiskers were bounded by (1 1 1) planes form to minimize total energy.•The morphology of SiC whisker was discussed from the perspective of atomic diffusion. The SiC whiskers were prepared on carbon matrix by high hydrogen-containing silicone oil (H-PSO) as raw materials. Based on the results of previous experiments, we further studied the effect of non-heat treatment factor on growth of SiC whiskers, including type and thickness of carbon matrix, size of embedded powders, and growth catalysts. The results showed that the powder particle size and the matrix should be properly matched to facilitate whisker growth. When grown on 2 mm graphite plate, the particle size was 150 μm-180 μm, the SiC whiskers were straight, smooth and homogeneous, showing hexagonalprisms morphology, which were bounded by low-energy (1 1 1) planes, rather than silicon oxide coating. The change of particle size led to the change of concentration of reaction gas and partial pressure of oxygen, which resulted in the difference content of silicon oxide in whiskers, showing hexagonalprisms or cylindrical morphology. Adding growth catalyst, the whisker morphology was not as good as the whisker grown without catalyst, and the growth mechanism had changed.