High-voltage Lorentz electron microscopy studies of domain structures and magnetization processes in pearlitic steels

Abstract

Abstract Pearlitic steels with volume fractions of pearlite from 5 to 100% have been studied using a high-voltage electron microscope and by measuring the Barkhausen activity. The results indicate that the microstructural parameters that affect the coercivity most strongly are the volume fractions and grain sizes of ferrite and pearlite. In electron microscope studies it was observed that domain walls were particularly strongly pinned in cementite lamellae in pearlite grains. A simple model is derived from these observations, which correctly predicts the coercivity of a large number of steels.