Physical and mechanical properties of highly textured polycrystalline Nb4AlC3 ceramic

Abstract

Highly textured polycrystalline Nb4AlC3 ceramic was fabricated by slip casting in a strong magnetic field followed by spark plasma sintering. Its Lotgering orientation factor was determined on the textured top and side surfaces as f(00l) ∼1.0 and f(hk0)=0.36, respectively. This ceramic showed layered microstructure at the scales ranging from nanometers to millimeters. The as-prepared ceramic had excellent anisotropic physical properties. Along the c-axis direction, it showed higher hardness, bending strength, and fracture toughness of 7.0 GPa, 881 MPa and 14.1 MPa m1/2, respectively, whereas higher values of electrical conductivity (0.81×106 Ω-1 m-1), thermal conductivity (21.20 W m-1 K-1) and Young's modulus (365 GPa) were obtained along the a- or b-axis direction. © 2011 National Institute for Materials Science.