Fine-grained SiC was hot-pressed with Al, B, and C additives under 150MPa at 1850 ◦C. The grains had an equiaxed shape and the average grain
size was 360 nm in as-sintered SiC. Al was detected at grain boundaries of Al, B, C-doped SiC by using energy-dispersive X-ray spectroscopy. The
uni-axial compression tests were performed at constant crosshead speed at 1772 ◦C in He. The strain rates of Al, B, C-doped SiC in the low-stress
region were ∼1 order of magnitude faster than those of B, C-doped SiC. The stress exponent of Al, B, C-doped SiC was 1.4 in the higher stress
region, and increased to 2.6 with decreasing stress. The transition of the stress exponent, which is often observed in the superplasticity of metals
and oxides, e.g., ZrO2, appeared in fine-grained SiC also.
各種検索
サポート
ヘルプ