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Austempered ductile iron (ADI) isincreasingly being used for the manufacturing of mechanical componentssubjected to rolling contact fatigue (RCF), such as gears and cams. Severalauthors studied the RCF behavior of ADI with different nodule counts and austemperingtemperatures. They found that ADI resistance toRCF increases as austempering temperature decreases and nodule count increases.Graphite nodules act as preferential sites for crack nucleation. Consequently,the use of surface treatments could offset the negative effect of the nodules.The authors of the present workstudied the rolling contact fatigue (RCF) behavior of PVD CrN and TiN coatedADI. The coating thickness was close to2.5 µm. It was found that the RCF resistance of coated samples is lower thanthat of uncoated samples. Failures in coated samples are mainly characterizedby coating delamination. Graphite nodules present on the substrate surface actas preferential sites for coating fracture and subsequent delamination due to thelarge properties difference with respect to coatings. Consequently, theapplication of multilayer coatings could enhance ADI resistance to RCF bymodifying the properties gradient between substrate and coating.On this basis, the aim of this work is to study theRCF behavior of ADI samples PAPVD coated with Ti/TiN. The effect of the TiNlayer thickness on the RCF life is also evaluated. Coatings were applied bycathodic arc deposition (CAD) in an experimental reactor using processingparameters specifically selected for ADI. Deposition times were adjusted toobtain a Ti interlayer thickness of about 0.3 µm and different TiN layerthicknesses. RCF tests were performed in a flat washer type testing rig, usinga thrust ball bearing as a counterpart. The maximum contact pressure was set at1400 MPa. RCF tests results were analyzed using the two-parameter Weibulldistribution. The rolling track of the tested samples was examined by usingSEM.