A magnetic-based nondestructive evaluation (NDE) method, which employs Barkhausea effect and measurement of hysteresis loops, is developed and used to correlate the magnetic and mechanical properties in ultra low carbon (ULC) steel. The NDE test equipment offers the capability to detect small deviations from linearity that occur in the stress-strain curve well below the 0.2 offset strain. Results show that three properties extracted from the experimental results, jumpsum and jumpsum rate (derived from the Barkhausen spectrum), and differential permeability (derived from the B-H loops), vary sensitively with small deformations well below the 0.2 offset strain in ULC steels; however coercivity is a slowly varying function of small applied strains.
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