中國(guó)有色金屬學(xué)報(bào)(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 35 No. 2 February 2025 |
（1. School of Mechanical Engineering, Guizhou University, Guiyang 550000, China;
2. Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
3. Ningbo Institute of Dalian University of Technology, Ningbo 315000, China）
Abstract:Microstructural characterization, mass loss tests, hydrogen evolution tests, electrochemical measurements, and corrosion morphology observations were conducted to investigate the effect of the secondary phases on the corrosion behavior of the as-cast Mg-7Sn-1Zn-1Y (TZW711) alloy after solution treatment (T4) and aging treatment (T6). The results show that the T4-TZW711 alloy possesses the highest corrosion resistance in the early corrosion stage. This is because the dissolution of Mg2Sn reduces the cathodic current density and increases the charge transfer resistance (Rct). When the corrosion time is prolonged, the undissolved and clustered MgSnY phase will peel off from the T4-TZW711 alloy surface, thereby increasing the corrosion rate of the alloy. After aging treatment, the undissolved MgSnY phase is dispersed, which results in a lower localized corrosion sensitivity of T6-TZW711 alloy than that of the T4-TZW711 alloy, suggesting that the T6 treatment can enhance the corrosion resistance of Mg-7Sn-1Zn-1Y alloys.
Key words: Mg-Sn-Zn-Y alloy; heat treatment; MgSnY phase; electrochemical test; corrosion behavior
