Vibration study of CoCrNi (medium- entropy alloy) gears for marine applications

Abstract

High strength gears find their applications in challenging conditions ranging from aviation engines, heavy- duty machinery, and deep-sea marine vehicles. Gears in marine vehicles must withstand extreme deep-sea pressure, a highly corrosive environment, and susceptance to wear. Given that maintenance is practically impossible at sea, surface treatments and coatings have been employed to improve the life of such gears. Such practices come with their own drawbacks of being expensive or not performing well under intense wear. Hence, need arises for innovating high strength marine gears in terms of the use of novel materials. Medium Entropy Alloy, CoCrNi has captured researcher interest by its good strength-ductility synergy, high fracture toughness, high wear and corrosion resistance, without the formation of intermediate phases due to its stable single-phase FCC structure. Besides having properties that are consistent with the requirements for gear materials, the gears made of this alloy must also have less vibrations as compared to conventional marine gears to prevent the failure of gears by fatigue.