EXPRESS METHOD OF MAGNETIC PERMEABILITY AND SPECIFIC CONDUCTIVITY NON-DESTRUCTIVE TESTING OF PARTS PARTICULAR ZONES

摘要

FIELD: non-destructive testing.;SUBSTANCE: coil inductance is measured together with cylindrical samples having the length l_s five times more than their diameter d_s(L_{c.s. ).} then the samples are removed from the coil and the coil inductance is measured in the ambient air (L_c.a.), the magnetic permeability of chosen zone material μ_s= L_c.s./ L_c.a. is determined; the sample electrical R_s resistance is measured and its material conductivity σ is calculated by formula σ_s=4l_s/πR_s(d_s)² at that beforehand the transducer is affixed to the particular zone, the inductance of the transducer with the part L_p is measured and using the value of transducer ambient air inductance L_a the conditional part magnetic permeability in chosen zone is calculated by formula μ_p.c..=L_p/L_a then the correction coefficient is calculated by formula K_μ=μ_s /μ_p.c.. After that transducer is affixed to the zones of remaining i parts of the lot and L_pi is measured; then the zone conditional part magnetic permeability of every i-th part of the lot μ_p.c.i =L_p.i/L_a is calculated and magnetic permeability μ_p.i = μ_p.c.i.K_μis determined. In addition in the chosen zone of entire parts on the base equal to l_s and on a frequency of ω_s.⁼l/π(d_s)²μ_sσ_s the electrical resistance R_p is measured in the layer with thickness d_s; the conditional specific conductivity of the particular zone.;EFFECT: SUBSTANCE: σ_c=l_s/2R_p(d_s)² and the correction coefficient K_σ=σ_s/ σ_c are calculated For the remaining parts of the lot as well as for parts used in the articles in the same zones on the base l_s and on the same frequency of ω_s the R_pi is measured and σ_ci is calculated, then the zone specific conductivity of every i-th part is determined by formula σ_ip=K_σσ_ci.;EFFECT: development of the effective express method of magnetic permeability and non-destructive testing of specific conductivity in parts particular zones.