NIST Standard Reference Database 30
Last Update to Data Content: 2002
"Effect of Load on the Hardness of Hot Isostatically Pressed Silicon Nitride," R. Berriche and R.T. Holt, Journal of the American Ceramic Society, Vol. 76 [6], pp. 1602-1604 (1993), published by American Ceramic Society.Language: English
"Specimens EB4, EB9, EB11, and EB14 were prepared by hot isostatic pressing (HIPing) silicon nitride powder (Grade LC 12, H. C. Starck, Inc., New York) at a temperature of 1950 °C and a pressure of 210 MPa. For the first two samples the holding time at the maximum temperature and pressure was a few minutes, whereas the hold period was 5 h for EB11 and EB14. ... NT154, a commercially HIPed silicon nitride was purchased in the form of finished bend test bars (Norton/TRW Ceramics, Worcester, MA)."
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Material Specimen Mass Fractions Relative Density
# Label of Additives (%)
1 EB4 2% YO 81.8
2 EB9 2% YO + 1% AO 84.0
3 EB11 None 99.7
4 EB14 2% YO + 1% AO 99.5
5 NT154 4% YO 99.7
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Key to Table:
YO = Y2O3
AO = Al2O3
Relative Density = d/dtheoretical
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"... specimens were mounted in bakelite, ground flat using 500 and 600 grit paper, and polished with diamond paste (5 µm, 1 µm, and 0.25 µm). The hardness measurements in the load range 1 N to 5 N were made with a microhardness tester (Leitz Wetzlar, Rockleigh, NJ) using a Vickers diamond indenter tip. Tests at higher loads were performed on a servohydraulic machine (MTS Systems Corp., Minneapolis, MN) using the same Vickers tip. Optical microscopy (OM) and scanning electron microscopy (SEM) were used to examine the indentation impressions.
Hv = 1854 P/d2
where P is the load in grams and d is the length of the diagonal in micrometers. ... Each of the data points represents an average of measurements from five tests at each load in the range 1 N to 5 N and three tests at each load for loads above 5 N."
| Load ( N ) |
Diagonal Length ( µm ) |
Hardness ( GPa ) |
|---|---|---|
| 1 | 17 | 6.6 |
| 2 | 24 | 6.8 |
| 3 | 29 | 6.6 |
| 5 | 38 | 6.4 |
| 50 | 140 | 5.1 |
| 100 | 190 | 5.3 |
| 150 | 230 | 5.6 |
| 200 | --- | 5.2 |
Data were digitized from Figs. 1 and 2 of the reference.
| Load ( N ) |
Diagonal Length ( µm ) |
Hardness ( GPa ) |
|---|---|---|
| 1 | 13 | 11.9 |
| 2 | 20 | 10.0 |
| 3 | 25 | 9.0 |
| 5 | 32 | 9.6 |
| 50 | 110 | 7.5 |
| 100 | 160 | 7.6 |
| 150 | 200 | 7.5 |
| 200 | 230 | 7.6 |
Data were digitized from Figs. 1 and 2 of the reference.
| Load ( N ) |
Diagonal Length ( µm ) |
Hardness ( GPa ) |
|---|---|---|
| 1 | 7.9 | 29.1 |
| 2 | 13 | 23.6 |
| 3 | 16 | 21.4 |
| 5 | 22 | 18.5 |
| 50 | 77 | 15.8 |
| 100 | 110 | 14.8 |
| 150 | 130 | 17.3 |
Data were digitized from Figs. 1 and 2 of the reference.
| Load ( N ) |
Diagonal Length ( µm ) |
Hardness ( GPa ) |
|---|---|---|
| 1 | 8.3 | 25.8 |
| 2 | 13 | 20.9 |
| 3 | 17 | 18.5 |
| 5 | 23 | 17.3 |
| 50 | 82 | 14.0 |
| 100 | 110 | 15.5 |
| 150 | 130 | 16.0 |
| 200 | 160 | 15.3 |
Data were digitized from Figs. 1 and 2 of the reference.
| Load ( N ) |
Diagonal Length ( µm ) |
Hardness ( GPa ) |
|---|---|---|
| 1 | 7.5 | 32.1 |
| 2 | 13 | 24.3 |
| 3 | 17 | 20.0 |
| 5 | 22 | 17.8 |
| 8.9 | 32 | 16.6 |
| 21 | 51 | 15.5 |
| 44 | 69 | 16.7 |
| 50 | 79 | 14.6 |
| 100 | 110 | 15.3 |
| 110 | 110 | 16.3 |
| 150 | 130 | 15.3 |
| 200 | 150 | 16.1 |
Data were digitized from Figs. 1 and 2 of the reference.