THE MAGNETIC-PROPERTIES OF PEARLITIC STEELS AS A FUNCTION OF CARBON CONTENT

Specially prepared low-carbon steels with pearlite fractions varying f rom 0.19 to 100% have been used to study the independent effect of car bon content and microstructure on the structure-sensitive magnetic pro perties of low-carbon pearlitic steels. Increased magnetic hardness wi th carbon content has been observed in the initial magnetisation and h ysteresis curves. The changes in the magnetisation processes were inve stigated by studying the Barkhausen noise emissions and observing the domain wall motion directly using Lorentz electron microscopy. The inc rease in pearlite content significantly enhanced the effectiveness of cementite lamellae at pinning domain walls.