Influence of laser energy density on the microstructure and corrosion resistance of LPBF‐fabricated titanium‐based nanocomposites

Abstract As a high‐efficiency laser additive manufacturing technology, laser powder bed fusion (LPBF) has unparalleled advantages in the manufacture of titanium matrix composites. In this work, the effect of laser energy density (LED) on the forming quality, microstructure evolution, and corrosion resistance of LPBF‐fabricated nanographene oxide reinforced titanium matrix nanocomposites (GO/TC4) was investigated. The results show that the optimal surface roughness and relative density of GO/TC4 nanocomposites fabricated by LPBF are 11.8 μm and 99.40%, respectively. The microstructure is mainly acicular α/α′‐Ti, accompanied by a small amount of β‐phase grain boundaries. When the LED is increased to 58.33 J/mm 3 , the self‐corrosion potential of GO/TC4 sample reaches 0.345 V in 3.5 wt% NaCl solution, and the GO/TC4 58.33 nanocomposite exhibits the highest corrosion resistance. The results revealed that the corrosion products on the surface of the samples were mainly composed of a passivation film of TiO 2 and a small amount of Al 2 O 3 .