|Spoluautoři BORDEASU Ilare, MITELEA Ion|
The 17-4 P.H. stainless steels called also “half austenitic steels” are used especially in manufacturing high speed aircrafts and missiles because those devices are running at temperatures over the maximum value allowed for the high resistance alloys with aluminum and manganese (over 200°C). The same stainless steels can be used also in manufacturing hydraulic machineries subjected to intense cavitation erosion. They combine the most attractive properties of austenitic steels (weld ability and deformability) and martensitic steels (high mechanical and cavitation erosion resistance). Their modifications can be obtained through a solution quenching followed by ageing. The present research examines the effects of various solution treatment temperature (950 respective 1050˚C) upon the cavitation erosion behavior for a steel with 17% Cr, 4% Ni, 2% Mo, 2% Co and 2% Mn. The cavitation erosion tests were carried out in a vibratory facility with piezoceramic crystals. The eroded surfaces were analyzed, after different testing times, through optical and scanning electron microscopy.