Microstructural and Corrosion Characteristics of Alloying Modified Layer on 5083 Al Alloy by Electrical Discharge Alloying Process with Pure Silicon Electrode

作者：Stambekova Kuralay; Lin Hung Mao; Uan Jun Yen^*

来源：Materials Transactions, 2012, 53(8): 1436-1442.

DOI：10.2320/matertrans.M2012131

• electrical discharge alloying
• silicon electrode
• rapid solidification
• corrosion

This study examines the surface modification of 5083 Al alloy by electrical discharge alloying (EDA) process, using pure Si as an electrode. Al alloy surface was modified by the EDA process to explore the effect of machining parameters (discharge current, pulse duration and duty factor) on the thickness, hardness and roughness of the alloyed layer. Samples were analyzed by scanning electron microscopy (SEM), electron probe analysis (EPMA) and X-ray diffraction. Since pure Si was used as an electrode, the alloyed layer had high concentration of Si from 2 mass% (the position in the layer at substrate side) to 12 mass% (the position in the layer close to surface side). Experimental results reveal that the thickness of the alloyed layer had a concave downward relationship with the discharge current and pulse duration. High hardness (similar to Hv 250) of the alloyed layer was obtained. The results of X-ray diffraction indicate that the primary phase in the substrate was alpha-Al, while there were composite phases containing alpha-Al and Si particles in the alloyed layer. Additionally, the alloyed layer exhibited as good corrosion resistance as 5083 Al alloy in aqueous NaCl. [doi:10.2320/matertrans.M2012131]

• 出版日期2012-8