METHOD OF COATING THICKNESS MEASUREMENT DURING PLASMA-ELECTROLYTIC OXIDATION PROCESS Russian patent published in 2024 - IPC G01B11/06 C25D11/02 

FIELD: electrochemical treatment.

SUBSTANCE: invention relates to electrochemical processing, particularly to plasma-electrolytic oxidation (PEO), and can be used to measure thickness of coating during PEO process. Method of determining thickness of coating during plasma-electrolytic oxidation includes measurement of radiant energy during production of coating, wherein after 1–50 s after the beginning of treatment, radiation is periodically recorded in the wavelength range of 200–1,100 nm with a width of the informative region of 50–900 nm at time intervals Δt_i with holding of 0.1–5 s, its average intensity is calculated, and the thickness of the coating is calculated is determined by formulas , where i is the number of the time interval; N is the total number of time intervals in the processing cycle; Δt_i is duration of time interval, s; is the average rate of growth of the coating on the time interval i, defined as the ratio of the difference in thickness of the coating on the current h_i and previous h_i-1 time intervals to the difference of the current t_i and the previous t_i-1 time intervals, mcm/s; I_av(i) is the average radiation intensity for the time interval i, having a stable correlation with the average growth rate ν_i, p.u.; k₁ and k₂ are empirical coefficients depending on the nature of the processed material and composition of the electrolyte, determined from calibration curves, mcm.

EFFECT: high accuracy of determining thickness of oxide coating for timely termination of plasma-electrolytic oxidation.

1 cl, 12 dwg, 2 tbl