Cu, Cr 등 천이원소가 첨가된 Al-1.4Mn-1.0Zn 합금을 심재로 하여 제조된 콘덴서 핀용 알루미늄 클래드 박판의 특성

Properties of Aluminum Clad Sheets for Condenser Fins Fabricated with Transition Elements(Cu, Cr) added to Al-1.4Mn-1.0Zn Base Alloys

In the current study, Al-Mn-Zn alloys are strip-cast and used as the base alloy for the core of aluminum clad sheets used in automotive condenser fins. Transition elements such as Cu and Cr are added to the base core alloy in order to improve the properties of the clad sheets. The AA4343/Al-Mn-Zn-X(X: Cu, Cr)/AA4343 clad sheets are fabricated by roll bonding and further cold-rolled to a thickness of 0.08 mm. Clad sheets were intermediately annealed during cold rolling at $450^{\circ}C$ in order to obtain 40% reduction at the final thickness. Tensile strength and sag resistance of the clad sheets are improved by Cu additions to the core alloy, while corrosion resistance is also increased. Cr-additions to the clad sheets enhance sag resistance and provide low enough corrosion, although tensile strength is not improved. The effect of Cu and Cr additions on the properties of the clad sheets is elucidated by microstructural analysis.