Microalloying boron carbide with silicon to achieve dramatically improved ductility
No Thumbnail Available
Authors
An, Qi
Goddard III, William A.
Issue Date
2014
Type
Citation
Language
Keywords
DFT , boron carbide , ductility , mechanical properties , microalloying
Alternative Title
Abstract
Boron carbide (B4C) is a hard material whose value for extended engineering applications such as body armor is limited by its brittleness under impact. To improve the ductility while retaining hardness, we used density functional theory to examine modifying B4C ductility through microalloying. We found that replacing the CBC chain in B4C with Si–Si, denoted as (B11Cp)–Si2, dramatically improves the ductility, allowing a continuous shear to a large strain of 0.802 (about twice of B4C failure strain) without brittle failure. Moreover, (B11C)–Si2 retains low density and high hardness. This ductility improvement arises because the Si–Si linkages enable the icosahedra accommodate additional shear by rotating instead of breaking bonds.
Description
Citation
Publisher
American Chemical Society
License
In Copyright
Journal
Volume
Issue
PubMed ID
ISSN
1948-7185