Corrosion Behaviour Between Al–Zr Alloy Conductor and Cu Transition Terminal via Sc Addition

Abstract

The influence of Sc microalloying on corrosion behaviour between Al-0.2Zr alloys conductor and Cu sheet have been studied in 0.1 M Na 2 SO 4 + 0.05 M NaCl weak acid solution. The observations of corroded morphologies of the Al-0.2Zr alloys conductor were obtained by scanning electron microscopy and transmission electron microscopy. After same short-term service, slight local corrosion and pitting pits occur on the surface of Al-0.2Zr alloy, and corrosion products mainly adhere along grain boundaries of Al-0.2Zr-0.1Sc alloy. After same long-term service, there are many large and saggy corrosion pits on the surface of Al-0.2Zr-0.1Sc alloy, while only some staircase corrosion marks appear on the surface of Al-0.2Zr alloy. Al 3 Sc and Al 3 (Zr,Sc) may reduce the electrochemical heterogeneity and the electrochemical reaction of precipitated precipitates on subgrain boundaries and inter-subgrains, thus improving corrosion resistance via Sc addition.