Role of nanostructure on reaction and transport in Ni/Al intermolecular reactive composites

Mathew J. Cherukara, Purdue University
Karthik Guda Vishnu, Purdue University
Alejandro Strachan, Birck Nanotechnology Center, Purdue University

Date of this Version

8-30-2012

Citation

Mathew J. Cherukara, Karthik Guda Vishnu, and Alejandro Strachan Phys. Rev. B 86, 075470. Vol. 86, Iss. 7

Comments

This is the published version of Mathew J. Cherukara, Karthik Guda Vishnu, and Alejandro Strachan. 30 August 2012. Role of nanostructure on reaction and transport in Ni/Al intermolecular reactive composites. First published in the Physical Review B and is available online at: http://dx.doi.org/10.1103/PhysRevB.86.075470

Abstract

We use molecular dynamics to characterize the exothermic chemistry of Ni/Al nanolaminates for various temperatures, periodic lengths, and in the presence of extended defects. We show that the reaction is mass diffusion controlled for bulk nanolaminates, with the overall reaction time scaling with the square of the mean transport distance. The presence of voids or free surfaces not only leads to a significant decrease in reaction time (by as much as a factor of 5), but fundamentally changes the nature of the reaction. Free surfaces and voids running across several periods provide a mechanism for ballistic mass transport and change the scaling between reaction time and characteristic transport distance.

Discipline(s)

Nanoscience and Nanotechnology

 

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