resumo
Magnesium is one of the lightest metals and magnesium alloys have good strength to weight ratio making than very attractive for many particular applications [l]. The main drawback of magnesium alloys is their high,corrosion susceptibility. Improving the corrosion protection by deposition of thin hybrid films can expand the areas of applications of relatively cheap magnesium alloys. This work aims at investigation of new anticorrosion coating systems for magnesium alloy AZ31B using hybrid sol-gel films. The sot-gels were prepared by copolymerization of 3-glycidoxypropyltrimethoxysilane (GPTMS), titanium alcoxides and special additives which provide corrosion protection of magnesium alloy. Different compositions of sot-gel systems show enhanced long-term corrosion protection of magnesium alloy. The sot-gel coatings exhibit excellent adhesion to the substrate and protect against the corrosion attack. Corrosion behavior of AZ31B substrates pre-treated with sot-gel derived hybrid coatings was tested by Electrochemical Impedance Spectroscopy (IBIS). The morphology and the structure of sol-gel films under study were characterized with SEM/EDS techniques.
categoria
Engineering; Materials Science
autores
Galio, AF; Lamaka, SV; Zheludkevich, ML; Dick, LF; Muller, IL; Ferreira, MGS
nossos autores
Mário Guerreiro Silva Ferreira
Professor(a) Jubilado(a)
Mikhail Zheludkevich
Investigador Principal Convidadoagradecimentos
The authors acknowledge the financial support from CAPES BEX 1348/06-0, GRICES, MULTIPROTECT project (Contract No IP- 011783), and Portuguese Fundacao para a Ciencia e Tecnologia (contract POCTI/CTM/59234/2004). The FCT grants FRH/BPD/26481/2006 and SFRH/BPD/20537/2004 are also gratefully acknowledged.