Atomistic mechanisms underlying plastic flow at ultralow yield stress in ductile carbon aerogels
文献类型：期刊论文
| 作者 | Conter, Giorgio; Xiao KL(肖凯璐) ; Wu XQ(吴先前); Goddard III, William A.; Fortunelli, Alessandro
|
| 刊名 | NANOSCALE
 |
| 出版日期 | 2023-11-28 |
| 页码 | 8 |
| ISSN号 | 2040-3364 |
| DOI | 10.1039/d3nr04067d |
| 通讯作者 | Goddard III, William A.() ; Fortunelli, Alessandro(alessandro.fortunelli@cnr.it) |
| 英文摘要 | We investigated carbon aerogel samples with super low densities of 0.013 g cm-3 (graphite is 2.5) and conducted compression experiments showing a very low yield stress of 5-8 kPa. To understand the atomistic mechanisms operating in these super low density aerogels, we present a computational study of the mechanical response of very low-density amorphous carbonaceous materials. We start from our previously derived atomistic models (based on the DynReaxMas method) with a density of 0.16 g cm-3 representing the core regions of carbon aerogels. We considered three different phases exhibiting either a fiber-like clump morphology interconnected with string-like units or a more reticulated framework. We subjected these phases to compression and shear deformations and analyzed the resulting plastic response via an inherent-structure protocol. Strikingly, we find that these materials possess shear plastic relaxation modes with extremely low values of yield stress, negligible with respect to the finite values predicted outside this "zero-stress" region. This is followed by a succession of two additional regimes with increasing yield stress values. Our analysis of the atomistic relaxation mechanisms finds that these modes have a collective and cooperative character, taking the form of nanoscopic shear bands within the clumps. These findings rationalize our experimental observations of very low-stress plastic deformation modes in carbon aerogels, providing the first steps for developing a predictive multi-scale modeling of the mechanical properties of aerogel materials. The phenomenon of plastic flow at ultra-low yield stress in super-low density ductile carbon aerogels from experimental measurements to its theoretical understanding via atomistic structures and deformation mechanisms. |
| 分类号 | 二类/Q1 |
| WOS关键词 | REACTIVE FORCE-FIELD ; REAXFF |
| 资助项目 | Division of Chemical, Bioengineering, Environmental, and Transport Systems ; Italian Cineca Supercomputing Center[CA21101] ; COST Action ; COST (European Cooperation in Science and Technology)[CBET-1805022] ; COST (European Cooperation in Science and Technology)[CBET-2005250] ; COST (European Cooperation in Science and Technology)[CBET-2311117] ; NSF |
| WOS研究方向 | Chemistry ; Science & Technology - Other Topics ; Materials Science ; Physics |
| 语种 | 英语 |
| WOS记录号 | WOS:001112658200001 |
| 资助机构 | Division of Chemical, Bioengineering, Environmental, and Transport Systems ; Italian Cineca Supercomputing Center ; COST Action ; COST (European Cooperation in Science and Technology) ; NSF |
| 其他责任者 | Goddard III, William A. ; Fortunelli, Alessandro |
| 源URL | [http://dspace.imech.ac.cn/handle/311007/93560]  |
| 专题 | 力学研究所_流固耦合系统力学重点实验室(2012-) |
| 推荐引用方式 GB/T 7714 | Conter, Giorgio,Xiao KL,Wu XQ,et al. Atomistic mechanisms underlying plastic flow at ultralow yield stress in ductile carbon aerogels[J]. NANOSCALE,2023:8. |
| APA | Conter, Giorgio,肖凯璐,吴先前,Goddard III, William A.,&Fortunelli, Alessandro.(2023).Atomistic mechanisms underlying plastic flow at ultralow yield stress in ductile carbon aerogels.NANOSCALE,8. |
| MLA | Conter, Giorgio,et al."Atomistic mechanisms underlying plastic flow at ultralow yield stress in ductile carbon aerogels".NANOSCALE (2023):8. |
入库方式： OAI收割
来源：力学研究所
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