“…Such a combination of phases makes ADI resistant to tribological wear [ 20 , 21 ] and cracking. First of all, austempered ductile iron shows a tendency towards surface hardening as a result of the phase transformation of austenite [ 22 , 23 , 24 , 25 , 26 ] into martensite under load. This effect is attributable to the fact that austenite subjected to deformation [ 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ], meeting specific conditions, is transformed into martensite, referred to as deformation martensite.…”