METHOD OF DETERMINATION OF MOMENT OF TERMINATION OF ELECTROLYTIC PLASMA REMOVAL OF COAT Russian patent published in 2004 - IPC

FIELD: electrolytic and plasma treatment of surfaces. SUBSTANCE: proposed method includes measurement of alternating- current component and analysis of its change in time. Alternating-current component is fed to band-pass filter at limiting frequency of 500-700 and 1300-1500 Hz and voltage "u" at filter output is measured. Magnitude u₀ of threshold voltage is determined by averaging magnitude "u" for 20-40 s from beginning of treatment and time lengths t_k and "t" are read off if voltage "u" reaches magnitude (0,5-0,6)•u₀., 50-70 s after beginning of treatment. Termination of reading of time t_k is set by magnitude of voltage "u" equal to (0,7-1,0)•u₀.. Moment of termination is set as magnitude "t" reaches value (1,4-1,6)•t_k. Area S cleaned from coat is calculated by formula S = k•t_k, where k is empirical coefficient of proportionality. In case voltage "u" does not reach magnitude (0,5-0,6)•u₀, 50-70 s after beginning of process, process is discontinued. EFFECT: improved quality of surface. 1 dwg, 1 tbl, 1 ex