
Micrograph of induction hardened AISI G-3500 gray iron
illustrating retained austenite at the lobe tip.
(Magnification 200X, 3% Nital)

Micrograph of induction hardened AISI G-3500 gray
iron illustrating crack propagation into the induction
hardened case. (Magnification 100X, 3% Nital)