NON-DESTRUCTIVE METHOD DETERMINING DEFORMING CAPABILITY OF TECHNOLOGICAL RESIDUAL STRESSES Russian patent published in 1998 - IPC

FIELD: measurement technology, determination of deforming capability of technological residual stresses in surface layer of articles from metals and alloys with various electromagnetic properties. SUBSTANCE: increased accuracy in determination of deforming capability of residual stresses without destruction or damage of tested object is achieved by measurement of amplitude-phase-frequency characteristics of section of surface. In this case frequency f of signals fed to tested surface forms diminishing sequence and values of amplitudes G of input voltage form increasing sequence satisfying relation Gxf= const. By measurement of amplitude-phase-frequency characteristics one determines residual stresses by formula , where q is deforming capability of technological residual stresses, f is frequency of measuring signal, G is amplitude of measuring signal, cosϕ is cosine of frequency of row ( Kf=1...2 ), Kf is coefficient taking into account physico-chemical properties of material of tested article ( Km=0...1 ). EFFECT: increased accuracy in determination of deforming capability of residual stresses. 1 dwg