Effects of Component Ratio and Mechanical Activation on Combustion in the (Ti + 2B) + (Ti + C) System
N. A. Kochetov
Merzhanov Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences, Chernogolovka, Russia
Keywords: combustion, mechanical activation, SHS, titanium diboride, titanium carbide
Abstract
The effects of the content of Ti + 2B and Ti + C mixtures and mechanical activation (MA) on the burning rate, the yield of the mixture after MA, and the morphology and phase composition of combustion products of the (Ti + 2B) + (Ti + C) composition has been investigated. During Mechanical activation of the Ti + 2B mixture for 5 min leads to mechanochemical synthesis of TiB2 product. Mechanochemical synthesis does not occur when adding Ti + C powder to the activated Ti + 2B mixture. Increasing the content of Ti + C in the (Ti + 2B) + (Ti + C) mixture leads to deterioration of the compressibility of samples after MA. The burning rate of the initial (Ti + 2B) + Ti + C) mixtures decreases with increasing content of Ti + C. Samples of the combustion products of the initial mixtures retain integrity after the synthesis. Mechanical activation doubles the burning rate of samples from the Ti + C mixture. The burning rate of the activated Ti + 2B) + (Ti + C) mixture increases with increasing content of Ti + C, and samples of the products are dispersed during combustion. For a mixture of equal mass fractions of the initial Ti + 2B powder and the activated Ti +C powder, the dependence of the burning rate of the mixture on the content of Ti + C in it has a minimum; if the investigated composition is dominated by the Ti + 2B mixture, the product samples retain integrity.
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