Behavior of hydrogen in structural defects in metal rubbing surfaces

Defects in the metal structure of the rubbing surfaces (pores, fractures, and dislocations) are considered to be magnetic traps for hydrogen and impurity elements. As a result of the interaction of hydrogen with carbon, not only is methane formed in the metal, but also other hydrocarbon homologous (from ethane to hexane), the number of which increases with time (two orders of magnitude or more). Because methane is formed with a reduction of the volume, which creates a vacuum in the defects facilitating the diffusion of hydrogen and other gaseous elements and impurities. The vacuum in the defects determines the incubation period before irreversible changes begin in the mechanical properties (embrittlement) of hydrotreated materials.