A microstructural approach to the chemical reactions during the spark plasma sintering of novel TiC–BN ceramics

• Published in: Ceramics international Vol. 46; no. 10; pp. 15982 - 15990
• Main Authors: Shaddel, Shahrzad, Sabahi Namini, Abbas, Pazhouhanfar, Yaghoub, Delbari, Seyed Ali, Fattahi, Mehdi, Shahedi Asl, Mehdi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2020
• Subjects: Characterization; Chemical reaction; h-BN; Spark plasma sintering; TiC; Characterization; Spark plasma sintering; Chemical reaction; h-BN; TiC
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2020.03.148

In this work, the monolithic TiC and h-BN doped ceramics were spark plasma sintered at 1900 °C for 10 min under 40 MPa pressure. The sinterability and physical-mechanical qualifications of as-produced specimens were studied to assess the impacts of the h-BN additive on TiC-based composites. Adding h-BN did not have any evident effect on the relative density so that both series of specimens achieved the same values around 95%. The X-ray diffraction (XRD) and microstructural evaluations proved the in-situ generation of TiB, TiB2, TiC and C phases. Although the monolithic TiC samples reached an average hardness of 3128 HV100 g, this value decreased by ~7% when h-BN was added to TiC. Finally, the monolithic sample showed a higher flexural strength (504 MPa) compared with the doped sample (429 MPa).