Study of mechanical and tribological properties of Ti–6Al–4V alloy fabricated by powder bed fusion laser beam

Powder bed fusion laser beam, as one of the most promising forming technologies, offers unmatched benefits over traditional processing, particularly in the production of Ti–6Al–4V. The influence of laser line energy density (LLED) on the forming surface, phase composition, micro-hardness, tensile characteristics and wear resistance of Ti–6Al–4V alloy were explored to disclose the evolution of mechanical and tribological properties. According to the findings, the LLED causes ‘depressions’ and ‘highlands’ between nearby scanning tracks. The phase composition did not alter appreciably as LLED increased. Micro-hardness and tensile characteristics increased initially, then declined, and the value of maximum micro-hardness and ultimate tensile strength were 388.17 HV_0.2 and 1197.5 MPa, respectively. Furthermore, when the LLED is 0.24 J mm^–1, the wear resistance is optimal under the aviation lubricant medium, with an average friction coefficient of 0.1505 and volume wear rate of 6.95*10⁻⁸ mm²*N⁻¹, and a wear mechanism of mild furrow wear and adhesion wear.