Options
Electrochemical Dissolution Characteristics and Electrochemical Micromachining of Ti6Al4V Alloy Fabricated by Direct Metal Laser Sintering Method
Journal
Electrocatalysis
ISSN
18682529
Date Issued
2022-11-01
Author(s)
Tak, Mukesh
Gaur, Bhanupratap
Ravi, B.
Mote, Rakesh G.
Abstract
Owing to exceptional mechanical properties of titanium alloys, mechanical processing has been a challenge. Additive manufacturing of titanium alloys to produce various artefacts via direct metal laser sintering (DMLS) enables a wide range of mechanical properties via controlling the process parameters. In this study, Ti6Al4V alloys are fabricated using DMLS at different laser powers, and their electrochemical dissolution behaviour is investigated. The laser sintered Ti6Al4V alloys were primarily found to consist of martensite α´ phase due to the rapid cooling after the sintering. Electrochemical impedance spectroscopy (EIS) shows that the DMLSed fabricated Ti6Al4V is composed of a duplex oxide barrier structure, consisting of the outer porous passive layer and inner compact passive layer. Electrochemical dissolution characterization based on the potentiodynamic polarization results revealed that the lowest dissolution potential is shown by the Ti6Al4V alloy prepared at higher laser power, which indicates the ease of dissolution compared with other samples prepared at lower laser powers. A prior-β grain size was found to be increased in the alloys fabricated with increasing laser power. The coarsening of the prior-β grain fabricated at higher laser power promotes the anodic dissolution due to the higher density of martensites, thereby increasing the localized corrosion attack. The average material removal rate increases for the samples fabricated at higher laser powers. The electrochemical micromachining studies have shown that the samples prepared using a high laser power response yield an improved surface finish. Graphical Abstract: [Figure not available: see fulltext.]
Subjects