Comparison of Wear Behavior of Ductile Iron in Austempered and Quenched- ‎Tempered Conditions ‎

In this study, wear behavior of the pearlitic ductile cast iron samples with the same hardness achieved by applying two different ‎heat treatment cycles have been studied. A number of these samples after austenitzing at 900°C were quenched into a molten salt ‎bath of 290°C for holding time of 120 minutes followed by cooling in air. The rest of the samples after being austenitized under ‎the same conditions were quenched in oil and then were tempered in 505°C for 75 minutes. To compare wear behavior of the ‎aforementioned cast irons, the “pin on the disk” method based on the ASTM-G99 standard was used. In this method, the ‎samples were prepared in the form of disks and were worn by 52100 steel pins for a constant distance of 1000 meters and the ‎sliding speed of 0.08 m/s at the applied loads of 25 N and 75 N. Based on the results obtained from the wear surface ‎observations, mass reduction and friction coefficient measurements of the worn samples, it was revealed that at the lower ‎applied load, the quenched and then tempered samples exhibited a higher wear resistance comparing to the austempered samples. ‎Whereas at the higher applied load (75 N) the inverse result was achieved.‎