Portal de Periódicos da CAPES

Microstructure and Corrosion Properties of Mg-<I>x</I>Sn-5Al-1Zn (<I>x</I>=0, 1, 5 and 9 mass%) Alloys

2010; Volume: 51; Issue: 3 Linguagem: Inglês

10.2320/matertrans.m2009308

1347-5320

Kyung Chul Park, Byeong Ho Kim, Hisamichi Kimura, Yong Ho Park, Ik Min Park,

Hydrogen Storage and Materials

In the present work, the corrosion properties of Mg-xSn-5Al-1Zn (x=0, 1, 5 and 9 mass%) alloys have been investigated. Potentiodynamic polarization and immersion tests were carried out in 3.5% NaCl solution of pH 7.2 at room temperature to measure the corrosion properties of Mg-xSn-5Al-1Zn (x=0, 1, 5, and 9 mass%) alloys. Microstrucral analysis shows the Mg17Al12 and Mg2Sn phase were mainly precipitated along grain boundaries. With increase of the Sn contents, the volume fraction of the secondary phases, i.e. Mg17Al12 and Mg2Sn phase, was increased. The corrosion resistance of Mg-xSn-5Al-1Zn alloys was improved by the Sn addition. Especially, the AZ51-5 mass%Sn alloy characterized the superior corrosion resistance in the studied alloys. It seems that the presence of Sn stabilized the Mg(OH)2 layers on the surface of Mg alloys and the secondary phases effectively formed semi-continuous structures, resulting in a drastic improvement of corrosion resistance of the Mg alloys.