The effect of carburizing time and wear behavior of the carburized, hardened Cr and Ni-Cr steel were studied. For this purpose, Cr and Ni-Cr steel containing 0.15%C was taken. The specimen of 8mm diameter and 6.5mm thick from each steels... more
The effect of carburizing time and wear behavior of the carburized, hardened Cr and Ni-Cr steel were studied. For this purpose, Cr and Ni-Cr steel containing 0.15%C was taken. The specimen of 8mm diameter and 6.5mm thick from each steels were carburized at 945oc at three different holding times (1 hr, 2hr, 3hr respectively) and quenched at salt water. Surface hardness was measured by using Rockwell hardness testing machine. Wear test were carried out by using pin on disc type apparatus under dead loads of 1.5kg,2kg and 3kg at a linear speed of 2.64 ms-1 in ambient air. The sliding distance was 6336m.The structure then observed the worn surface by optical microscopy. It has been found that Ni increases the amount of retained austenite content in the case of the carburized low carbon Cr steel. Ni reduces the surface hardness, case hardness and core hardness of the low carbon Cr steel. The presence of retain austenite along with the martensite that the surface hardness found lower than the maximum hardness of the both the steels. Wear rate increases with the increases of the dead load. Wear rate of Ni-Cr steel found higher than that of Cr steel due to the presence of Retain austenite in Ni-Cr steel.
