Composites based on the cubic boron nitride (c- BN) have recently attracted increasing interest due to the possibility of the synthesis of materials with unique properties such as super-hardness, combined high hardness and low friction, high corrosion resistance, attractive thermal and electrical properties. There is an increasing number of composites based on the c- BN matrix with addition of Ti compounds such as TiC, Ti3SiC2, TiN. In order to understand the origin of the exceptional properties of these materials it is necessary to have a good comprehension of the multiphase composition and microstructure of these materials. The lack of this knowledge is result of difficulties in characterization of the multiphase materials using conventional methods.
In the presented paper we used element selective spectroscopies for estimation of the content of different compounds of Ti formed during the technological processes in composites. The X-Ray Photoelectron Spectroscopy (XPS), Auger Electron Spectroscopy (AES), and X- Ray Absorption Spectroscopy (XAS) was chosen to estimate the amount and kind of formed compound. Additionally the X-Ray diffraction measurements were performed on the same samples. Due to the existence of many compounds with not very different crystal structure the quantitative phase analysis of diffraction pattern was not possible. The analyses of element selective spectroscopies data proves the existence of several Ti compounds (TiC, TiB2, TiSi2, TiN) and allowed to evaluate the percent of Ti bonded in each of compound, therefore are the perfect tools for the investigation of micro-chemical mechanism taking place in composites.
Acknowledgements
This work was supported in part within European Community program ICA1-CT-2000-70018 (Centre of Excellence CELDIS)
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