|About this Abstract
||MS&T23: Materials Science & Technology
||Hybrid Organic-inorganic Materials for Alternative Energy
||Self-healing Engineered Multilayers Coatings for Protection of Magnesium Alloy AZ31B
||Andrei Jitianu, Mario Aparicio, Jadra Mosa, Zainab Abd Al-Jaleel, Jennifer Guzman, Lisa C. Klein
|On-Site Speaker (Planned)
Magnesium alloys are attractive due to their low density, high strength, good thermal and electrical conductivity. Hybrid glasses (HG) obtained from melting gels (MG) can protect AZ31B against corrosion. However, HGs are nonporous materials and cannot be used for doping with self-healing agents such as Ce(III) ions. To overcome this, the AZ-31B substrates were first coated with mesoporous coatings using tetramethyl orthosilicate, (TMOS), cetyltrimethylammonium bromide (CTAB) and Ce(NO3)3•6H2O, with the molar ratio TMOS:CTAB:EtOH:H2O:Ce(NO3)3•6H2O=1:0.16:35:5:1. After elimination of the organic surfactant these coatings were sealed using diluted MGs prepared using 70% methyltriethoxysilane (MTES) and 30% dimethyldimethoxysilane (DMDES). Electrochemical analysis (Anodic Polarization and Electrochemical Impedance Spectroscopy) was performed in 0.35% NaCl solutions. The impedance and phase curves of this measurement show four-time constants associated with the thick outer coating of melting gels (≥ 104.3Hz), Ce-doped silica coating (102.7Hz), charge transfer related to the corrosion process (101.3Hz) and ion diffusion process (≤ 10-1 Hz).