Applications of analytical electron microscopy to guide the design of boron carbide

Abstract

A materials-by-design approach is currently being undertaken to accelerate the development of future generations of high-performance ceramics, metals, and composites. The design approach involves iterations of physically based simulations, 1-3 material processing, 4,5 and bulk material testing, [6][7][8] which in this combination, completes a "materials-by-design loop". 9 Boron carbide 10 is being researched as a model system due to its ultrahigh hardness and low density. 11,12 Within this effort, research has focused on understanding the effects of microstructure and composition on the physical mechanisms which govern the inelastic response of boron carbide during high-rate, large deformation, and non-hydrostatic loading conditions typical of ballistic events. These mechanisms include bulk quasi plasticity, 13,14 stress-induced amorphization, [15][16][17][18] fracture and fragmentation, 7,19-21 and granular flow. 22 It has also been discovered/validated that mechanical performance of boron carbide (i.e., hardness