Primary nanocracks in nitrides, borides, and carbides of refractory metals

Abstract

A model is proposed that can be used to calculate the length of a nanocrack in a solid body. The nanocrack length in nitrides, borides, and carbides of refractory metals turned out to be in the range 1<L<3 nm. Theoretical and experimental methods for studying nanocracks are discussed. The theory gives a length interval 0<L<2 nm for silicon polycrystals. X-ray and electron microscopic methods give the thickness of cracks in the metal in the range of tenths and hundredths of a micron. The recently proposed method of fractoluminescence for the destruction of minerals with a duration of signals of about 50 ns, and the time interval between them varied from about 0,1 to 1 μs, made it possible to reveal nanocracks in oligoclase during the destruction of its surface in the range of 10<L<20 nm, which coincides with the one in proposed by us model. More examples of the formation of nanocracks in solids can be cited. In other words, we propose to call the direction of condensed matter physics «physics of nanocracks», which differs from the «theory of cracks» both in its experimental detection and in the method of its calculation.

Keywords

• nanocrack
• surface layer
• metal
• fracture
• surface
• model
• micron