Evaluating surface mechanical properties and wear resistance of Ti–6Al–4V alloy subjected to ultrasonic pulsed waterjet peening

Abstract

The alloy Ti–6Al–4V is widely utilized in various industrial applications, yet its inherent susceptibility to mechanical wear and friction has led to performance limitations. Addressing this, surface modification techniques have been employed to improve material surface properties. Among these, ultrasonic pulsed waterjet (UPWJ) peening emerges as a viable solution due to its ability to improve surface characteristics without causing excessive plastic deformation, unwanted thermal effects, or surface contamination. This study is focused on the influence of UPWJ peening parameters, particularly traverse speeds ranging from 200 to 1000 mm/s, on wrought Ti–6Al–4V (grade 5). Comprehensive characterization encompassed surface roughness, scratch hardness, and reciprocating wear analysis. Post-test examinations, including FE-SEM, CLSM, and EDS were employed to provide detailed microstructural and elemental insights. The results revealed that traverse speeds between 800 and 1000 mm/s yielded a remarkable 55 % enhancement in scratch hardness. Additionally, wear behavior exhibited a correlation with UPWJ traverse speed; notably, a speed of 900 mm/s indicated a 12 % improvement in wear resistance under a 40 N load. This research highlights the interplay relationship between UPWJ peening parameters and Ti–6Al–4V's wear performance, contributing to its broader understanding and application potential.