Fabrication of Textured Porous Ti₃SiC₂ by Slip Casting under High Magnetic Field and Microstructural Evolution through High Temperature Deformation

To clarify the effect of constraint conditions on the kink formation, fabrication process of the texture and porosity controlled Ti₃SiC₂ polycrystals was investigated and microstructural evolution during high temperature deformation was examined in it under high temperature uniaxial compression tests at 1200°C. Dense textured Ti₃SiC₂ sintered body was fabricated by slip casting in the high magnetic field of 12 T and following pressureless sintering at 1400°C for 1 h. The porosity of the textured Ti₃SiC₂ was controlled by dispersing polymethyl methacrylate (PMMA) particles into the textured Ti₃SiC₂ as a spacer media. The highly textured Ti₃SiC₂ polycrystals with porosity of 8.4 vol% and 16.7 vol%, respectively, were successfully fabricated by the slip casting in the high magnetic field. After the high temperature uniaxial compression perpendicular to the c-axis of the textured structure, both the porous and dense Ti₃SiC₂ showed kink formation, which is a common deformation mode for anisotropic layered materials. However, the average rotation angles of the kink boundaries were higher in the porous specimen than in the dense specimen. Since the crystal rotation is necessary for the kink formation, kink bands would be preferably developed in the porous area due to its weaker constraint than in the dense area. It can be concluded from the microstructural analysis that the constrain factor caused by the neighbor grains affects the crystalline rotation, resulting in the kink boundary formation with different rotation angles.