| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Engineering Ceramics: Microstructure-Property-Performance Relations and Applications
|
| Presentation Title |
D-10: Crystal Orientation Dependence of Mechanical Properties of β-Si3N4 Grains in High Thermal Conductive Silicon Nitride Ceramics Measured Using Microcantilever Beam Specimens |
| Author(s) |
Mami Tanabe, Junichi Tatami, Motoyuki Iijima, Hiromi Nakano, Tatsuki Ohji, Tukaho Yahagi, Takuma Takahashi, Daichi Minami |
| On-Site Speaker (Planned) |
Mami Tanabe |
| Abstract Scope |
High thermal conductivity Si3N4 ceramics with excellent mechanical reliability are required for high-power power devices. For this purpose, it is important to investigate the mechanical properties of grains and grain boundaries in Si3N4 ceramics. In this study, crystal orientation dependence of the mechanical properties of β-Si3N4 grains in high thermal conductivity silicon nitride ceramics was investigated using microcantilever beam specimens. The bending strength of the microcantilever specimens was higher than that of bulk specimens at 8.65 to 19.97 GPa, which should be the intrinsic strength of β-Si3N4 grain. Similar to Young's modulus, it increased with decreasing angle between the longitudinal direction of the microcantilever specimen and the c-axis of β-Si3N4. Yield stress, the starting point of nonlinear deformation in the stress-strain curve, also showed the same trend as strength. TEM observation revealed that plastic deformation caused by multiple slips of dislocations occurred in the bending test at room temperature. |