Nanosecond Dynamics of Destruction of the Surface Layer
of a Heterogeneous Nanocrystalline Solid (Sandstone)
under the Friction
V. I. Vettegren’a,*, G. A. Sobolevb, A. V. Ponomarevb,
I. P. Shcherbakova, and R. I. Mamalimova
Translated by O. Borovik-Romanova
a Ioffe Institute, Russian Academy of Sciences,
Politekhnicheskaya ul. 26, St. Petersburg, 194021 Russia
b Schmidt Institute of Physics of the Earth, Russian Academy of Sciences,
ul. Bol’shaya Gruzinskaya 10–1, Moscow 123242 Russia
Correspondence to: * e-mail: Victor.Vettegren@mail.ioffe.ru
Received 10 October, 2016
Abstract—It has been found that the friction of a heterogeneous material, namely, sandstone, leads to the appearance of triboluminescence. The phenomenon of triboluminescence corresponds to luminescence of ≡Si–O free radicals and Fe3+ ions. These radicals and ions are formed as a result of the breaking of Si–O–Si bonds in nanocrystals of quartz and feldspar entering into the composition of the sandstone. The time dependence of the triboluminescence intensity represents a set of flashes, each having the duration of a few nanoseconds. It has been assumed that triboluminescence flashes correspond to the appearances of cracks in the material. Сrack opening is found to be approximately 180 nm. The size distribution of the cracks is exp-onential.
DOI: 10.1134/S1063783417050298