Fabrication of Al/Mg Clad Material Using a Horizontal Tandem Twin Roll Caster

Abstract

This study was aimed that Fabrication of Al/Mg clad material using a horizontal tandem twin roll caster. Magnesium is the lightest of structural metals combining high mechanical strength and low density. However, magnesium is low corrosion resistance. Aluminum alloys and magnesium alloys were fabricated as an Al/Mg composite using aluminum alloys as protective layers, improvement of the corrosion resistance of the magnesium alloys can be expected. In this study using twin roll casting process and downward melt drag process. And also in-line rolling process was used. A horizontal tandem twin roll caster consists of three kind of twin roll. AZ121 was cast by first twin roll, this is first strip. Downward melt drag process was used for casting of A1050, this is second strip. In case of narrow roll gap, AZ121 was melted by A1050 due to increased heat transfer coefficient. In this study, bonding could be better that cladding of aluminum on third twin roll would rather than cladding of aluminum on second twin roll. Thickness of clad strip was 5.5 mm, aluminum layer was 1.1 mm, magnesium layer was 4.3 mm. cladding ratio was 1.1 : 4.3. Mixed layer was 70-90μm in bonding region. Each diffuse layer of Al layer and Mg layer was 10 μm. Primary crystal size of Mg layer was 77μm at mixed layer region, 19μm at center region, 83μm at surface region.