Evaluation of corrosion resistance of aluminum silicon alloys manufactured by LPBF

The paper reports on the corrosion behavior of two aluminum alloys, with different silicon content, manufactured by means of laser powder bed fusion. The results of potentiodynamic tests and intergranular corrosion tests are discussed in order to evaluate the effect of film formed during manufacturing and successive stress relieving and plane orientation. The results show on both alloys the propagation of localized attack by selective dissolution of aluminum along borders of melt pool. A clear reduction of pitting potential was recognized on the surface as produced by the manufacturing process and less marked variations between different planes. The tests did not reveal a systematic variation of the pitting potential between the two alloys.