Abrasive wear in Austempered Ductile Irons: A comparison with white cast irons

• Wear tests of ductile cast irons in comparison to a white cast iron were performed.
• The higher tenacity was verified in the ADI 300 °C.
• In the begin of the wear tests the most resistant material was the white cast iron.
• From 120 to 196 h the ADI 300 °C was the most resistant.
• The transformation of retained austenite into martensite was verified.

This work aims to evaluate the mechanical properties and the abrasive wear resistance of a group of nodular cast irons and a white cast iron. The samples were produced and heat treated. The materials characterisation was performed using optical and scanning electron microscopy. In the wear tests, a rotating device with sand as the abrasive material was constructed and used. To assess the tests results, the mass loss values of the specimens were analysed. Until 120h of testing, the white cast iron was observed to have a lower weight loss compared with that of other materials. From 144 h until the end of the test, at 196 h, an inversion of the performance occurred for ductile irons, which exhibited the lowest wear rate until the end of the test. This result is due to the presence of retained austenite in the ductile iron. This fact, besides allowing an increase in toughness that was verified in the impact tests, provides an increase in abrasion resistance due to the subsequent transformation of the retained austenite into martensite.