Cavitation erosion resistance enhancement of martensitic stainless steel via low-temperature plasma carburizing

Abstract This work presents the potential of low-temperature plasma carburizing treatments for improving the cavitation erosion resistance of martensitic stainless steel (MSS). As-hardened AISI 420 MSS samples were treated via dc plasma carburizing at 450 °C for 12 h. The cavitation erosion behaviors were compared with that of an untreated steel sample tempered at 220 °C for 1 h. Cavitation erosion tests were performed with an ultrasonic vibratory apparatus in accordance with the ASTM G32-10 standard. The nominal incubation period of the carburized samples was approximately three times higher than that of the untreated sample (23 h versus 7.8 h, respectively). The cavitation erosion behavior was discussed in terms of mechanical surface properties (hardness (H) and elastic modulus (E)) obtained via the nanoindentation technique and respective H/E, H 2 /E, and H 3 /E 2 ratios.