Abstract
The microstructure of a commercial polycrystalline cubic boron nitride (PCBN) tool material was studied using scanning electron microscopy with energy-dispersive X-ray analysis and transmission electron microscopy with electron energy loss spectroscopy and energy filtered TEM. These results were compared with results from X-ray diffraction and thermodynamic calculations. It is shown that this PCBN material consists of cBN both as micrometre-sized and nanometre-sized grains. The micrometre-sized grains show primarily straight phase boundaries and little reaction with the surrounding matrix. The matrix consists of mainly TiCN, with grains ranging from nanometres to sub-micrometres. The C and N content in TiCN varies, indicating a system far from equilibrium. Only small reaction zones are found and the major reaction is the one between Al and O, forming Al2O3. It is also shown that it is possible to prepare samples thin enough for TEM/EFTEM/EELS studies, enabling the study of minor reaction phases like TiB2.
| Original language | English |
|---|---|
| Pages (from-to) | 249-255 |
| Number of pages | 7 |
| Journal | International Journal of Refractory Metals and Hard Materials |
| Volume | 27 |
| Issue number | 2 |
| DOIs | |
| State | Published - Mar 2009 |
| Externally published | Yes |
Funding
This work was carried out with the financial support by Sandvik Tooling and the Swedish Research Council. I would like to express my gratitude to Drs Alexandra Kusoffsky, Ernesto Coronel and Leif Dahl at Sandvik Tooling for guidance and fruitful discussions concerning thermodynamic calculations, EFTEM, EELS and XRD.
Keywords
- EFTEM
- Microstructure
- SEM
- TEM
- cBN