HIGH-STRENGTH ALUMINUM ALLOY FIN MATERIAL AND PRODUCTION METHOD THEREOF

摘要

Provided are: an aluminum alloy fin material for heat exchangers, said aluminum alloy fin material having a small thickness of 35-50 mum, undergoing little springback in corrugating, having such a pre-brazing strength as to facilitate fin-shaping, having a high post-brazing strength, having excellent errosion resistance and excellent self corrosion resistance, and showing an excellent sacrificial anode effect; and a production method thereof. The fin material comprising, in terms of mass%, 0.9-1.2% of Si, 0.8-1.1% of Fe, 1.1-1.4% of Mn, 0.9-1.1% of Zn, together with, as impurities, not more than 0.05% of Mg and not more than 0.03% of Cu, and the balance being inevitable impurities and Al; ([Si]+[Fe]+2[Mn])/3 being restricted to 1.4-1.6%; the sheet thickness being 35-50 mum; the pre-brazing tensile strength being not higher than 215 MPa; the solidus temperature being 620oC or higher; the post-brazing tensile strength being 140 MPa or higher; the post-brazing electrical conductivity being 45% IACS or higher; and the post-brazing spontaneous potential being -730 to -760 mV. In the production method, steps for hot rolling, cold rolling, intermediate annealing and final cold rolling are respectively specified.