On hardening silver nanocubes by high-velocity impacts: a fully atomistic molecular dynamics investigation
- 136 Downloads
Gradient nanograins (GNG) creation in metals has been a promising approach to obtain ultra-strong materials. Recently, R. Thevamaran et al. (Science 354:312 in 2016) proposed a single-step method based on high-velocity impacts of silver nanocubes (SNC) to produce almost perfect GNG. However, after certain time, these grains spontaneously coalesce, which compromises the induced hardening and other mechanical properties. To better understand these processes, a detailed investigation at the atomic scale of the deformation/hardening mechanisms are needed, which is one of the objectives of the present work. We carried out fully atomistic molecular dynamics (MD) simulations of silver nanocubes at high impact velocity values using realistic structural models. Our MD results suggest that besides the GNG mechanisms, the observed SNC hardening could be also the result of the existence of polycrystalline arrangements formed by HCP domains encapsulated by FCC ones in the smashed SNC. This can be a new way to design ultra-strong materials, even in the absence of GNG domains.
We would like to thank the Brazilian agency FAPESP (Grants 2013/08293-7 and 2016/18499-0) for financial support. This research was also supported by resources supplied by the Center for Scientific Computing (NCC/GridUNESP) of the São Paulo State University (UNESP). Computational support from the Center for Computational Engineering and Sciences at Unicamp is also acknowledged.
- 17.Shackelford JF (2015) Introduction to materials science for engineers, 8th edn. Pearson, LondonGoogle Scholar
- 21.Zang A, Stephansson O (2009) Stress field of the earth’s crust, 1st edn. Springer, HoutenGoogle Scholar
- 31.Jona F, Marcus PM (2007) First-principles study of the high-pressure hexagonal-close-packed phase of mercury. J Phys: Condens Matter 19:036103Google Scholar
- 34.Jona F, Marcus PM (2004) Metastable phases of silver and gold in hexagonal structure. J Phys: Condens Matter 16:5199–5204Google Scholar