Corrosion behavior characterization of 7050 aluminum alloy based on in-situ observation and machine learning
NIU Tong1, ZHANG Na2, XIONG Xilin2
1. NCS Testing Technology Co., Ltd., Beijing 100081, China; 2. Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China
Abstract：The in-situ observation of corrosion behavior of T7451 and as-cast 7050 aluminum alloys in 3.5% NaCl solution was performed. The corrosion morphology feature and precipitated phase composition were analyzed by scanning electron microscopy (SEM), and the relationship between grain orientation and corrosion behavior was analyzed statistically by combining with EBSD. Based on 196 pieces of historical literature data, the importance ranking of corrosion behavior characteristics were conducted by Pearson correlation screening and Backforward algorithm. It was found that the corrosion behavior of 7050 aluminum alloy started around the precipitated phase, and the corrosion depth and range increased with time, which was accompanied with crack initiation. Among them, the precipitated phases were most distributed in the crystal faces of <112>, <114> and <324>. Potentiodynamic scan showed that the self-corrosion current density increased with the precipitated phase density. In addition, the importance ranking of SEM and machine learning showed that Cu, Ti, Fe and Mg all appeared in the precipitated phase, and their influence on the corrosion behavior was most significant. This study could effectively guide the corrosion resistance design of aluminum alloys.
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2024, Vol. 42 
