Addressing amorphization and transgranular fracture of B₄C through Si doping and TiB₂ microparticle reinforcing

Abstract

Over the last two decades, many studies have contributed to improving our understanding of the brittle failure mechanisms of boron carbide and provided a road map for inhibiting the underlying mechanisms and improving the mechanical response of boron carbide. This paper provides a review of the design and processing approaches utilized to address the amorphization and transgranular fracture of boron carbide, which are mainly based on what we have found through 9 years of work in the field of boron carbides as armor ceramics.

Modeling Deformation and Fracture of Boron-Based Ceramics with Nonuniform Grain and Phase Boundaries and Thermal-Residual Stress

“…Above a small threshold, or with the availability of more systems, plasticity may reduce hardness and peak load capacity as the tendency to flow inelastically increases [52]. As noted in the present findings and experiments [68], a transition from inelastic shear (e.g., twinning) to amorphization may inhibit ductility in B 4 C. Regardless, a consistent trend among current and prior work is a decrease in average fracture activity ξ with increasing average slip or deformation twinning η. Along with local crack tip blunting, this should contribute to a higher toughness, even if ultimate strength is reduced.…”

“…The high surface roughness of the cracked material suggested intergranular fracture in the composite. In contrast, pure B 4 C failed predominantly by transgranular fracture, similar to observations in other studies [68]. The same physical mechanisms were observed in both static and dynamic flexure.…”

Recent advances in glass‐ceramics: Performance and toughening mechanisms in restorative dentistry

“…When a large number of dislocations are accumulated in it, the strength of the grain itself decreases, resulting in cracks in the interior of the grain (Figure 2A). 56 Transcrystalline rupture can be either a macroscopic plastic fracture or macroscopic brittle fracture. Transcrystalline rupture follows the grains in the wood, not the edges of the puzzle.…”

Investigation of the effect of impurity of precursor materials on Si‐doped boron carbide properties

“…It is preferable for armoring helicopters and crafting body armor since it has a very low theoretical density (2.52 g/cm 3 ) 11,12 . However, the amorphization of boron carbide under high shear stress may cause it to fail when used as armor plating or other military protection materials 13–20 . Zhao et al.…”

“…11,12 However, the amorphization of boron carbide under high shear stress may cause it to fail when used as armor plating or other military protection materials. [13][14][15][16][17][18][19][20] Zhao et al showed that amorphization occurs with the deformation of the chains connecting the icosahedron of the B 4 C. 21 Crystalline B 4 C's major peaks are 481,531, 700-900, 1004, and 1086 cm −1 associated with B-C-B chain stretching, icosahedron release, B-B bonding, chain rotation, and icosahedron breathing modes, respectively. 22 When an amorphous band occurs three new peaks form.…”