Decomposition fracture induced

It is by no means certain that the mechanism of fracture-induced decomposition reaction will be the same as that described for slow decomposition. For example, when the crack is running at its maximum velocity, chemical bonds are broken on a time scale comparable to that required for a bond to make one vibration. It can be imagined, therefore, that those bonds which are near their maximum amplitude of vibration when the crack approaches wiU be most likely to break, probably leaving the surface in a highly active state and producing free radicals in the gas phase. Such a process was envisaged by Taylor and Weale... 

Mechanical treatment alone may be sufficient to induce significant decomposition such processes are termed mechanochemical or tribo-chemical reactions and the topic has been reviewed [385,386]. In some brittle crystalline solids, for example sodium and lead azides [387], fracture can result in some chemical change of the substance. An extreme case of such behaviour is detonation by impact [232,388]. Fox [389] has provided evidence of a fracture initiation mechanism in the explosions of lead and thallium azide crystals, rather than the participation of a liquid or gas phase intermediate. The processes occurring in solids during the action of powerful shock waves have been reviewed by Dremin and Breusov [390]. 

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