Insights into the fracture mechanisms and strength of amorphous and nanocomposite carbon
Insights into the fracture mechanisms and strength of amorphous and nanocomposite carbon
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DOI：
10.1103/physrevlett.96.185503
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发表时间：
2006-05-12
影响因子：
8.6
通讯作者：
Papaconstantopoulos, DA
中科院分区：
文献类型：
--
作者：
Fyta, MG;Remediakis, IN;Papaconstantopoulos, DA
紧束缚分子动力学模拟揭示了四面体非晶碳和纳米复合碳含金刚石微晶，两个最硬的材料的断裂机制和理想的强度。结果表明，在拉伸或剪切载荷下，纳米复合材料的断裂发生在晶粒间，因此其理想强度与纯非晶相相似。断裂发生在非晶基体中弱键合的sp（3）位点。另一方面，纳米金刚石夹杂物显着提高弹性模量，接近金刚石。
Tight-binding molecular dynamics simulations shed light into the fracture mechanisms and the ideal strength of tetrahedral amorphous carbon and of nanocomposite carbon containing diamond crystallites, two of the hardest materials. It is found that fracture in the nanocomposites, under tensile or shear load, occurs intergrain and so their ideal strength is similar to the pure amorphous phase. The onset of fracture takes place at weakly bonded sp(3) sites in the amorphous matrix. On the other hand, the nanodiamond inclusions significantly enhance the elastic moduli, which approach those of diamond.