Resemblance in Corrosion Behavior of Selective Laser Melted and Traditional Monolithic β Ti-24Nb-4Zr-8Sn Alloy

ACS Biomater Sci Eng. 2019 Feb 11;5(2):1141-1149. doi: 10.1021/acsbiomaterials.8b01341. Epub 2019 Jan 2.

Abstract

Distinct corrosion behavior was reported in multiphased titanium alloys prepared by additive manufacturing and by traditional technologies because of different phase constituents formed during processing. An open question is therefore raised: is there always different corrosion behavior of materials prepared by different methods? This work reports resemble corrosion behavior of selective laser melted and wrought single β-phase Ti-24Nb-4Zr-8Sn (Ti2448) in both NaCl solution and Hank's solution. The electrochemical measurements showed that both samples have close calculated polarization resistance and corrosion potential in NaCl solution, i.e., 4.99 ± 0.63 MΩ cm2 and -0.26 ± 0.01 V for the selective laser-melted Ti2448, and 4.42 ± 0.71 MΩ cm2 and -0.25 ± 0.01 V for the wrought Ti2448, respectively. Both samples reveal the same variation in weight change after 180-day immersion test in Hank's solution. Such resemblance in corrosion behavior without pitting morphologies is attributed to the formation of monolithic β-phase during processing, which demonstrates that titanium alloys with single phase show comparable corrosion behavior regardless of the manufacturing methods adopted.

Keywords: beta phase; corrosion behavior; resemblance; selective laser melting; titanium alloy.