|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Deformation and Transitions at Interfaces
||Observation and Characterization of Grain Boundary Complexions in Hot-pressed Boron Carbide
||Kristopher D. Behler, Scott D Walck, Christopher J Marvel, Jerry C LaSalvia, Martin P Harmer
|On-Site Speaker (Planned)
||Kristopher D. Behler
Multiple grain boundary complexion types, including possible liquid-like intergranular films (IGFs), were observed in boron carbide for the first time. The boron carbide samples were produced by hot-pressing high-purity boron carbide powders between 1800°C and 2000°C for 3 hours. Alumina, silica, and boron oxide additives were used to aide densification and foster the development of IGFs. Silicon-rich and silicon-aluminum-oxygen films with nominal thicknesses of <1 – 3 nm were observed in samples processed with multiple components. Based on theoretical considerations, additive compositions with multiple components may foster the development of IGFs by lowering their free energy through the likelihood of increased structural disorder. Aberration-corrected scanning transmission electron microscopy (AC-STEM) predominately showed multi-layer films at high-angle grain boundaries. X-ray energy-dispersive spectroscopy (XEDS) and energy-filtered TEM (EFTEM) were used to characterize the chemical nature of films and estimate their thicknesses. Experimental procedures, results, and analyses will be presented.