Hot Isostatic Pressing of Chromium Nitrides (Cr2N and CrN) Prepared by Self-Propagating High-Temperature Synthesis

• Published in: Journal of the American Ceramic Society Vol. 84; no. 9; pp. 2120 - 2122
• Main Authors: Hirota, Ken, Takano, Yoshihiko, Yoshinaka, Masaru, Yamaguchi, Osamu
• Format: Journal Article
• Language: English
• Published: Westerville, Ohio American Ceramics Society 01.09.2001; Blackwell; Wiley Subscription Services, Inc
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Exact sciences and technology; nitridation; pressing; self-propagating high-temperature synthesis; Structural ceramics; Technical ceramics; Self-propagating high-temperature synthesis; Chromium Nitrides; Sintering; Chemical preparation; Hot isostatic pressing; Fracture surface; Manufacturing; Experimental study; Microstructure; Non oxide ceramics; Structural ceramic
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1151-2916.2001.tb00969.x

Cr2N, CrN, and their mixtures (with desired fractions) have been prepared via self‐propagating high‐temperature synthesis (SHS) under a controlled nitrogen pressure, followed by hot isostatic pressing at 1300°C and 196 MPa under an atmosphere of argon gas. The combustion temperature increased as the nitrogen pressure increased. Single‐phase Cr2N was formed at 1040°C under a pressure of 0.18 MPa, and single‐phase CrN was formed at 1730°C under a pressure of 2 MPa. The mechanical properties of the dense nitride ceramics (99.2% of the theoretical density) have been examined; the Vickers hardness (11.2 GPa for CrN and 14.5 GPa for Cr2N) increased linearly as the fraction of Cr2N increased, whereas the fracture toughness (∼4.7 MPa·m1/2) and bending strength (∼355 MPa) are constant, regardless of the fraction of Cr2N/CrN.