2014 №10 (03) DOI of Article
2014 №10 (05)

The Paton Welding Journal 2014 #10
The Paton Welding Journal, 2014, #10, 22-25 pages  



E.O. Paton Electric Welding Institute, NASU. 11 Bozhenko Str., 03680, Kiev, Ukraine. E-mail:
Self-sustaining exothermal reaction of synthesis in multilayer foil consisting of intermetallic forming elements may proceed by means of self-propagation of high-temperature synthesis reaction front through foil (self-propagating high-temperature synthesis (SHS) or as a result of synthesis reaction running through the entire volume (autoinflammation (AI)). The latter is realized under the condition of foil heating up to a certain critical temperature, at which the synthesis reaction runs in the entire volume without external heat supply. In the work influence of foil heating rate on AI temperature was studied in the case of Ti/Al multilayer foil. It is shown that there exists a certain critical heating rate, below which foil AI is not observed, and at heating rates above the critical rate AI temperature decreases with increase of heating rate. Dependence of AI temperature on heating rate is nonmonotonic: at low heating rates AI temperature abruptly decreases, and at further increase of heating rate AI temperature remains practically unchanged. Such nonmonotonic dependence of foil AI temperature on heating rate is associated with running of the process of thermally activated solid phase reactions in it, which are accompanied by formation of intermetallic interlayers on the boundary between titanium and aluminium layers, preventing diffusion mixing of elements. With increase of heating rate, interlayer thickness decreases, promoting AI temperature lowering. 11 Ref., 4 Figures.
Keywords: multilayer foil, autoinflammation, electron beam vacuum deposition, thermal explosion, heat evolution
Received:                18.09.14
Published:               28.10.14
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