Patent ID: 7135239

Claim:
A composite material of a high-strength aluminium alloy, the composite material comprising: a core layer, a corrosion protective layer covering the top surface of the core layer, a brazing material layer applied to the corrosion protective layer, the core layer containing as alloying constituents 0.2 to 1.2% silicon Si; 0.8% maximum iron Fe; 0.15 to 1.0% copper Cu; 1.2% maximum manganese Mn; 1.2% maximum magnesium Mg; 0.04 to 0.35% chromium Cr; 0.2% maximum zinc; 0.25% maximum titanium Ti; and 0.3% maximum zirconium Zr with the balance being substantially aluminium Al; the corrosion protective layer containing as alloying constituents 0.6% maximum silicon Si; 0.7% iron Fe; 0.10 to 0.3% copper Cu; 0.9 to 1.5% maximum manganese Mn; 0.15% maximum magnesium Mg; 0.2% maximum chromium Cr; 0.2% maximum zinc; 0.30% maximum titanium Ti; and 0.3% maximum zirconium Zr with the balance being substantially aluminium Al; and the brazing material layer containing as alloying constituents 5% to 15% silicon Si; 0.8% maximum iron Fe; 0.3% maximum copper Cu, 0.1% maximum manganese Mn; 0.05% maximum magnesium Mg; 0.5% maximum zinc Zn; and 0.20% maximum titanium Ti with the balance being substantially aluminium Al.