Mechanisms of Self-Sustained Reaction in Mechanically Induced nanocomposites: Titanium Nitride and Boron

Article

Abstract

We report the results from the investigation of the mechanisms of self-sustained reaction in mechanically induced TiN/B nanocomposites. The exothermic displacement reaction, 3B + TiN β†’ BN + TiB2, with an adiabatic reaction temperature of 1905 K, was initiated through two different means: localized thermal heating and mechanical stimulation by high-energy ball milling. Comprehensive studies strongly indicate that the chemical interaction in the system involves three main stages. Solid-state mass transfer, likely the substitutional diffusion of B into a nitrogen deficient TiNx crystal lattice, is responsible for the formation of TiB2 during the first stage of the reaction (1350βˆ’1500 K) under ambient pressure. Thermal gravimetric analysis coupled with mass spectrometry demonstrated the evolution of gas phase nitrogen from TiN during an intermediate stage of the reaction in the temperature range of 1500βˆ’1800 K. Electron microscopy results show the formation of h-BN along the pores present in the initial composite, thus indicating reaction of gaseous nitrogen with boron during the final reaction stage. In addition, propagation characteristics of an oscillatory spin combustion regime in the TiNβˆ’3B system were analyzed using high-speed infrared imaging, which suggest a strongly nonlinear spin combustion mode.

Attributes

Attribute NameValues
Creator
  • J. M. Pauls

  • N. F. Shkodich

  • A. S. Mukasyan

Journal or Work Title
  • The Journal of Physical Chemistry C

Volume
  • 123

First Page
  • 11273

Last Page
  • 11283

ISSN
  • 19327455

Publication Date
  • 2019-04

Subject
  • Helios FIB

  • Magellan SEM

  • Titan TEM

Publisher
  • American Chemical Society

Date Created
  • 2019-08-15

Language
  • English

Departments and Units
Record Visibility and Access Public
Content License
  • All rights reserved

Digital Object Identifier

doi:10.1021/acs.jpcc.9b01521

This DOI is the best way to cite this article.