Mechano-chemical synthesis and characterization of Ti (C, N)-powder from TiN-MWCNTs/graphite

Abstract

The impact of blending and milling parameters on the formation of titanium carbonitride Ti (C, N) from titanium nitride (TiN), graphite and multiwalled carbon nanotube (MWCNT) have been explored. The three powders were varied in various proportions (wt.%), afterward subjected to blending in a Turbula Shaker mixer (mixed), and in a planetary ball mill (milled) separately. The processed and admixed powders were characterized using the field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and phase analysis were carried out with x-ray diffractometry (XRD). The impact of wet milling and dry blending on phases and morphology of the materials were also studied. The results show that the MWCNTs and graphite were consistently dispersed in the TiN while some isolated MWCNTs were seen after milling. From XRD results, it was discovered that phases of Ti (C, N), TiN and C_(graphite) were formed, although, a huge measure of TiN and CNTs were retained in last powder blend. This could upgrade the toughness of the formed Ti (C, N) after high-temperature sintering.

Keywords:

• Graphite
• MWCNTs
• milling
• mixing
• Ti (C
• N)
• TiN

Acknowledgments

The authors acknowledge the facilities, scientific and technical assistance of the Microscopy Australia node at the University of Sydney (Sydney Microscopy & Microanalysis). The authors are particularly grateful to Dr. Magnus Garbrecht and Jacob Byrnes for their technical assistance in the HRTEM and Fast Fourier Transformed (FFT) patterns experiments, respectively.

Additional information

Funding

The authors gratefully acknowledge the financial support from The National Research Foundation (NRF), South Africa and University of Johannesburg.