NIST Standard Reference Database 30
Last Update to Data Content: 2002
"Hot-Pressing of β-SiC Powder with Al-B-C Additives," B.W. Lin, M. Imai, T. Yano, and T. Iseki, Journal of the American Ceramic Society, Vol. 69 [4], pp. C67-C68 (1986), published by American Ceramic Society.Language: English
"Submicrometer β-SiC powder was used as a starting material. The average grain size was 0.28 µm and the powder was 98.9% pure (main impurities (mass fractions): free carbon 0.57 %, SiO2 0.36 %, and Fe and Al < 400 ppm). The powder was wet-mixed in benzene with 6 % Al, 1 % amorphous B, and 1 % carbon black. After the mixed powders were dried, they were compacted under 250 MPa hydrostatic pressure to obtain blocks with a density of (about) 58% of theoretical. The powder compacts were hot pressed at 1600 °C to 1800 °C for 30 min under 20 MPa to 60 MPa in an atmosphere of 100 kPa Ar using a graphite resistance electric furnace. The temperature was increased from room temperature to sintering temperature at 10 °C/min. Pressure was applied to the powder compact when the temperature reached 1000 °C and was released 10 min before the end of the holding time."
"The bulk density of the bodies was measured by the water immersion technique."Four-point bend test
"The specimen blocks obtained (27 mm by 27 mm by 4.5 mm) were cut and polished into bars (27 mm by2 mm by 4 mm) with diamond tools. ... The bending strength was measured by four-point bending, with an upper span of 10 mm, a lower span of 20 mm, and a crosshead speed of 0.5 mm/min. The surface roughness of the specimens was 0.2 µm (maximum height). The edges of the tensile side of the specimens were rounded with a radius of (about) 0.2 mm. Room-temperature bending strength was measured in air, and high-temperature measurement was done at 26 mPa while the temperature was held at 1200°C or 1400°C for 20 min. The numbers of specimens fractured at room temperature and the high temperatures were 6 to 10 and 3, respectively."
| Amount of Element ( formula units ) | Element ( no unit ) |
|---|---|
| 1 | Si |
| 1 | C |
| Hot-Press Pressure ( MPa ) | Hot-Press Temperature ( °C ) | Density ( g cm-3 ) |
|---|---|---|
| 20 | 1650 | 2.65 |
| 30 | 1650 | 2.85 |
| 40 | 1650 | 3.02 |
| 50 | 1650 | 3.08 |
| 60 | 1650 | 3.11 |
| 50 | 1600 | 2.86 |
| 50 | 1650 | 3.08 |
| 50 | 1700 | 3.16 |
| 50 | 1750 | 3.17 |
| 50 | 1800 | 3.17 |
Digitized data were obtained from Figures 1 and 2 of the paper.
| Hot Pressing Pressure ( MPa ) | Hot Pressing Temperature ( °C ) | Temperature ( °C ) | Flexural Strength ( MPa ) |
|---|---|---|---|
| 20 | 1650 | 22 | 350 ± 30 |
| 30 | 1650 | 22 | 370 |
| 40 | 1650 | 22 | 410 |
| 50 | 1650 | 22 | 485 |
| 60 | 1650 | 22 | 555 |
| 50 | 1650 | 1200 | 475 ± 50 |
| 50 | 1650 | 1400 | 325 |
| 50 | 1600 | 22 | 265 ± 30 |
| 50 | 1650 | 22 | 490 |
| 50 | 1700 | 22 | 520 |
| 50 | 1750 | 22 | 515 |
| 50 | 1800 | 22 | 575 |
| 50 | 1800 | 1200 | 490 ± 50 |
| 50 | 1800 | 1400 | 450 |
Digitized data were obtained from figures 1 and 2 of the paper.