INFLUENCE OF TENSILE-STRESS IN STEEL CABLES ON MAGNETIC BARKHAUSEN NOISE

The tensile stress of a cable is usually estimated by measurement of the force in some attached member. There are situations where it is important to know the actual stress in a cable and calculation may be difficult. The magnetic Barkhausen Noise (BN) method can be applied for stress measurement in ferromagnetic steel cables. The cable was led through the magnetizing and sensing coils and the induced noise was amplified and measured. 7- wire strands used in reinforced concrete, steel rope used by cranes and zinc-coated steel rope were the cables tested. The BN changed with applied tensile stress in all these materials. As tensile stress increased, magnitude of BN decreased and coercive force increased. The origin of this phenomenon was studied in relation to microstructure and XRD analysis. Based on the results utilization of BN for stress measurement is considered.