Corrosion behavior of selective laser melted Ti-6Al-4 V alloy in NaCl solution

• Corrosion of Ti-6Al-4 V manufactured by selective laser melting was investigated.
• SLM-produced alloy exhibits a worse corrosion resistance than Grade 5 alloy.
• The unfavorable corrosion resistance is related to the dominant α’ and less β–Ti.

Electrochemical measurements were performed to investigate the corrosion behavior of Ti-6Al-4 V alloy prepared by selective laser melting (SLM) and commercial Grade 5 sample for comparison. Electrochemical results showed that the SLM-produced sample possesses poorer corrosion resistance than the Grade 5 sample. Microstructure studies suggested that the SLM-produced sample is composed of dominant acicular α’ martensite and some prior β grains, unlike the typical α + β microstructure in Grade 5 sample. The unfavorable corrosion resistance of the SLM-produced sample is related to the considerably large amount of acicular α’ and less β–Ti phase in the microstructure compared to the Grade 5 sample.