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In the present work a so called long-life tube material (designated 3005LL) has been compared to standard AA3003 and AA3005 tube materials regarding post-braze strength and corrosion resistance. Furthermore the corrosion resistance of vacuum and controlled atmosphere brazed radiators have been evaluated. The effect of different tube and fin combinations on the corrosion properties has been investigated using 3005LL, AA3003 and AA3005 tube cores and AA3003, AA3003 + Zn and AA6063 fins. The results show a considerable increase in post-braze strength and corrosion resistance for 3005LL compared to the standard tube materials. Vacuum brazed radiators with 3005LL tubes have a significantly longer time to perforation than radiators with standard tubes. AA6063 fins in combination with 3005LL tubes proved to perform better than AA3003 fins due to a more beneficial electrochemical potential relation between tube and fin.

A new fin material, FA6815 (AA3003+Si, Zn, Zr) which corrodes at a low rate and gives cathodic protection to 3005LL tubes and AA4343 braze filler is presented. It shows better sagging resistance and twenty per cent higher post-braze strength than conventional AA3003 and AA3003+Zn. A new age hardening material, FA7827 (AlMgSi-type) for header and side supports is also presented. It has tensile strength of 180 MPa after brazing and fifteen days natural ageing. The corrosion resistance is improved compared to AA3003 and AA6060. These two new materials in combination with 3005LL tubes allow for improved performance and cost benefits by downgauging.