The influence of ultrasonic assistance on microstructure and properties of AlCoCrFeNi high-entropy alloy prepared by laser cladding

Abstract

The study investigates the influence of ultrasound on the microstructure and properties of AlCoCrFeNi fabricated by laser cladding. The results indicate that the grain size of AlCoCrFeNi prepared by ultrasonic assistance is smaller than that prepared without ultrasound. Moreover, employing ultrasound in the fabrication process of AlCoCrFeNi results in an improvement in its electrochemical corrosion resistance. This enhancement can be attributed to the homogenization of the microstructure and the reduction of microgalvanic couples. The wear resistance of AlCoCrFeNi is enhanced with the increase in ultrasound amplitude. The sample prepared using a 15 μm ultrasonic amplitude demonstrates the lowest friction coefficient of 0.3876 and the minimal wear loss of 40.8 mg. The tensile strength and elongation of AlCoCrFeNi are improved as the ultrasonic amplitude increases. The sample prepared using a 15 μm ultrasonic amplitude demonstrates the highest tensile strength and elongation, measuring 1039 MPa and 16.2%, respectively. The enhancement of mechanical properties can be attributed primarily to the grain refinement and the reduction of as-cast defects.