Deep-drawnability and some problems after form by deep-drawing of Al-Mg alloy sheets

Study on Al-Mg alloy sheets for forming use (2nd report)

Abstract

Deep drawing tests were conducted on Al-Mg alloy sheets after solution treatment at 400°C for one hour had been performed to eliminate a yield point. Some problems developed after deep drawing were also studied. The results obtained are as follows:
(1) As Mg content increases, larger limiting drawing ratio and higher formability were obtained when Al-Mg alloy sheets were solution treated. The addition of Cu in Al-Mg alloys resulted in the further improvement in the formability.
(2) From the X-ray study, excellent formability of these alloys was considered to be due to the increase of (200) planes parallel to the sheet plane.
(3) A visual check showed that water quenched samples developed better surfaces than air cooled samples. However, the addition of Cu decreased the difference of the surface finish between the water quenched and the air cooled samples.
(4) Formation of cracks was not observed after the 1.5 year immersion test had been conducted on circular cylindrical shells made by deep drawing.