摘要
Effect of direct aging of 170℃on corrosion behavior of laser powder bed fused AlSi10Mg(LPBF-AlSi10Mg)was studied by microstructure analysis,electrochemical analysis and X-ray photoelectron spectrometer.The results show that direct aging of 170℃has little effect on melt pool and Si cellular structure,but promotes the precipitation of nano-Si particles and releases the residual stress.With increasing aging time from 0 to 4 h to 24 h,the corrosion property of the LPBF-AlSi10Mg is deteriorated,which is evidenced by increased corrosion current density and decreased pitting potential and polarization resistance.With increasing the aging time,the thickness of the oxide film formed on surface of the LPBF-AlSi10Mg increases.The Si content of the oxide film of the sample aging for 4 h is the lowest,9.42 at.%,and it is the highest,18.62 at.%,for the sample aging for 24 h.The electrochemical noise analysis reveals that the middle-frequency contribution of the Hilbert spectrum is responsible for the deteriorated corrosion performance,which corresponds to metastable pitting initiated by nano-Si particles.
基金
This work was supported by the National Natural Science Foundation of China(No.52105409)
the Fundamental Research Program of Shanxi Province(No.20210302124042)
the High-level Talent Fund of North University of China(No.1101285710).
