Laboratory investigation of cavitation resistance of materials: Modified ultrasonically induced cavitation test method

Abstract

Cavitation erosion represents an actual problem in machines, whose components such as propellers, blades of hydraulic pumps and turbines, are exposed to high-speed flow of liquid. Research exhibited that hydraulic machinery parts during cavitation are exposed to mechanical action, electrochemical corrosion as well as local temperature increase. Therefore, high ductility, hardness, tensile strength, dynamic strength and corrosion resistance represent main properties in the choice of materials for producing hydraulic machinery parts. These properties depend on chemical composition and microstructure of materials. In this paper cavitation phenomenon was analyzed from laboratory investigation stand point by use modified ultrasonically induced cavitation test method. .

Kavitaciona erozija predstavlja uvek aktuelan problem kod mašina čiji su elementi, kao što su propeleri, lopatice vodnih turbina i pumpi, pri radu izloženi dejstvu brzog toka tečnosti. Dosadašnja istraživanja pokazala su da elementi hidrauličnih mašina u zoni dejstva kavitacije mogu biti izloženi ne samo mehaničkom dejstvu već i elektrohemijskoj koroziji, kao i lokalnom povišenju temperature. Otuda materijali za izradu elemenata hidrauličnih mašina treba da imaju visoku plastičnost, tvrdoću, čvrstoću, dinamičku čvrstoću i korozionu postojanost. Ova svojstva zavise pre svega od hemijskog sastava i strukture materijala. U radu je analiziran fenomen kavitacije sa aspekta laboratorijskih istraživanja primenom modificirane ultrazvučne metode. .