ABSTRACT
A TiCN-Co-Cr3C2-based cermet, with the addition of 5wt. % and 10wt. %Si3N4 and a reference sample without Si3N4 addition were prepared by the spark plasma sintering technique. The average hardness and fracture toughness of the 90TiCN-5Co-5Cr3C2(SN00) cermet-sintered specimens were e14.85±3.11 GPa and 6.78±0.61 MPaÖm, respectively. The cermet composition 85TiCN-5Co-5Cr3C2-5 wt. % Si3N4(SN05) enhanced the hardness and fracture toughness to 20.90±0.825 GPa and 7.23±0.45 MPaÖm, respectively. Further addition of 10 wt%Si3N4 with 80TiCN-5Co-5Cr3C2(SN10) decreased the hardness value to 16.18±0.279 GPa due to a decrease in the density of defects. However, the fracture toughness steadily increased to 9.34±3.10 MPaÖm. The cermet composition 85TiCN-5Co-5Cr3C2-5Si3N4 (SN05) showed an appreciable improvement in hardness and toughness values due to the formation of a core-rim structure, with the core consisting of TiCN and the rim with TiN, TiO2, TiSi, Co2C, CrN and Cr2Si.
Acknowledgements
Balasivanandha Prabu Shanmugavel thankfully acknowledges the fund (EEQ/2020/000620) received from the Science and Engineering Research Board, Department of Science and Technology, Government of India. The authors thank the Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, India for providing the spark plasma sintering facilities for this work.
Disclosure statement
No potential conflict of interest was reported by the author(s).