Anticorrosion of thermal sprayed Al-Zn-Si coating in simulated marine environments

作者：Yang H Q; Yao Z J^*; Wei D B; Zhou W B; Yin G X; Feng L X

来源：Surface Engineering, 2014, 30(11): 801-805.

DOI：10.1179/1743294414Y.0000000315

• Al-Zn-Si coating
• Corrosion behaviour
• Simulated marine environment
• Neutral salt spray corrosion
• Self-sealing behaviour
• Cathodic protection

The Al-Zn-Si coating was deposited on Q235 steel by thermal spray technology. The corrosion behaviour of the coating in simulated marine environments has been investigated through neutral salt spray test (NSS) and electrochemical test. Furthermore, the microstructure and the morphologies of the coating were detected by means of scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction. The results showed that the coating exhibited a dense homogeneous lamellar microstructure without obvious defects. There were different corrosion periods of the coating in the simulated marine environment, such as dissolution of Zn and Al particles, flocculent morphology, acicular crystals and self-sealing behaviour caused by corrosion products. Ultimately, a dynamic equilibrium was formed between the consumption of the coating and the generation of the corrosion product layer. Moreover, Tafel curves indicated that the E-corr and I-corr of the coating after NSS were lower than the substrate that had a sufficient driving force of the cathodic protection.

• 出版日期2014-11
• 单位南京航空航天大学