Improved wear resistance of 440C steel ball via ultrasonic strengthening grinding process

Abstract

The surface wear resistance of 440C steel balls is a critical factor in determining the operational reliability of their products. To address the challenges of enhancing the wear resistance of 440C steel balls, a method of ultrasonic strengthening grinding process (USGP) is introduced. The principle of this method employs ultrasonic waves to drive a mixture consisting of white corundum powder, strengthening liquid, and 440C steel balls. Subsequently, a multi-phase vibration, including steel balls, is generated and impacts a hard steel plate. Meanwhile, the evolutions of surface morphology, microhardness, microstructure, and residual stress of the treated 440C steel balls are revealed. The results demonstrate that the newly proposed USGP method is feasible. Then the deformation principle and microstructure evolution are studied in detail. Finally, the wear resistance of the 440C steel balls treated by USGP is tested. In comparison to the untreated samples, the friction coefficient and wear volumes of the USGP-treated samples were reduced by 38 % and 48.96 %, respectively. The present study highlights the potential of the proposed method for improving the wear resistance of various mechanical components, particularly steel balls.