METHOD FOR SURFACE MODIFICATION OF STRUCTURAL MATERIALS AND DETAILS Russian patent published in 2013 - IPC C23C14/32 C23C14/48 

FIELD: electrical engineering.

SUBSTANCE: method involves pulsed irradiation of treated surface by ionic component of plasma jet, at that products of electric explosion of conductors are used as the source of ionic component. Under irradiation coaxial-end electrode system is used and intensity of irradiation is selected based on the following ratio: $$\partial T/\partial t=P_h^2/\left(\chi \cdot \rho \cdot c\cdot T_m\right),$$ where χ, c, p are coefficient of heat conductivity, specific heat and density of the modified material respectively; P_h is power density of surface heating, GW/m²; T_m is melting point of the material; K, ∂T/∂t is cooling rate of melted surface layer, K/s. Pulse length of irradiation t* is evaluated on the basis of the ratio: $$t*=\left(\chi \cdot c\cdot \rho /\pi \right)\cdot {\left(\raisebox{1ex}{$T_m$}\!\left/ \!\raisebox{-1ex}{$P_h$}\right.\right)}^2,$$ value of current discharge integral at electric explosion of conductor meets the following condition: $$J={\displaystyle \underset{0}{\overset{t}{\int }}{j}_y^{2}dt}\ge J_{vb},$$ where J is current discharge integral, A²·s·m^-4; j_y is density of current through exploded conductor, A/m²; t is time of processing, s; J_vb is a tabular value of current integral for conductor transfer into vaporised state at boiling point, A²·s·m^-4. Process of electric explosion of a conductor in the end part of coaxial electrode is completed before discharge current reaches maximum value.

EFFECT: ability to reach maximum effectiveness of surface layer pseudo-amorphisation; improvement of quality in result of non-availability or controlled availability of macroparticles in plasma jet; controllability of processing parameters by selection of explosion moment.

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