抄録
In order to improve the corrosion resistance properties of structural steel (SS400) for bridge construction in corrosive environments, coatings of Al-Mg mixtures were deposited to protect SS400 substrates. This study observes the in-situ observation of cracks and focuses on the interfacial crack initiation and the corrosion fatigue crack behavior of the Al-Mg coating layers deposited on SS400 with different Mg concentrations. The investigation was carried out by using the four point bending (4PB) test in order to detect the interfacial strength between coatings and substrates of Al-Mg mixtures. Acoustic emission (AE) signals during the entire 4PB test were also measured in order to monitor the crack initiation and crack propagations and were analyzed by fast Fourier transform (FFT). The interfacial strength of Al-Mg coated SS400 decreases after immersion in NaCl aq.. There was little change in the interfacial strength of the Al-Mg coatings by different Mg concentrations in the ranges of present study.
