Ductile electrodeposited Al from a dimethylsulfone bath with trace amounts of tin chloride

Abstract

Al and Al alloys electrodeposited from a dimethylsulfone (DMSO2) bath are typically contaminated with S and Cl. Electrodeposited Al and Al alloys suffer from limited ductility since undesired impurities decrease plastic deformability. Herein, we report an electrodeposition process involving the use of a DMSO2 bath that realizes an Al product with tensile elongation as large as ∼30%. Doping of tin chloride in the DMSO2 bath resulted in a micrometer-scale grain microstructure with sub-µm Sn precipitates distributed along the grain boundaries of the electrodeposited Al. These Sn precipitates on the electrodeposits prevented S and Cl contamination, which is likely the main factor underlying the large tensile elongation in the electrodeposited Al. Furthermore, electrodeposition with varying concentrations of tin chloride pointed to that tin chloride showed enough impurities reducing ability even in trace amounts.