Nucleation of austenite from pearlitic structure in an Fe–0.6C–1Cr alloy

The nucleation site of austenite from pearlitic structure during reverse transformation at 1073 K in Fe–0.6C–1Cr (mass%) alloy was examined by means of electron backscattering diffraction. It was found that austenite preferentially nucleates at high-angle boundaries (HABs) of pearlitic ferrite. Some austenite nuclei maintain a near Kurdjumov–Sachs (K–S) orientation relationship (OR) with one or two pearlitic ferrites adjacent to the HAB. Austenite nucleated at the HAB face preferentially grows into the adjacent pearlitic ferrite, deviating greatly from the K–S OR.