Divergent pearlite in a manganese eutectoid steel

摘要: Abstract An unusual structural feature, diverging lamellae, has provided new insight to the influence of composition on transformations in steel. Samples from a high-purity ternary alloy iron containing 5.2 per cent manganese and 0.6 carbon were austenitized, isothermally transformed within temperature range 500°–675°C, quenched. Neither pearlite growth rate nor interlamellar spacing remain constant with time, but they vary over several orders magnitude during course single isothermal reaction. The nodules initially grow rapidly possess fine spacing; longer times, decreases increases. Nodules approaching impingement are characterized by very slow coarse at advancing interface. This is quite different time-invariant behavior observed plain-carbon steels. It shown that diffusion too give zone manganese-enriched austenite, so an austenite continuously changing content must cause phenomenon.