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A new evaporator plate alloy identified as FA7857 has been developed by Sapa. This alloy which is intended for CAB brazing, has been developed to meet the market needs for a material with good formability prior to brazing and a low susceptibility to filler liquid core penetration (sometimes termed LFM) during brazing. The excellent formability in the annealed condition, with an elongation of 26% and an Erichsen cup height of 9.2mm, makes this material highly suitable for pre-stretching prior to evaporator plate forming and brazing. An appropriate pre-stretch is 5% which eliminates the risk of LFM, while improving the uniformity of flow of the filler metal and the final corrosion performance. In SWAAT corrosion tests, brazed samples of the two-side clad sheet remained unperforated after 42 days of testing.

A new high strength aluminium alloy intended for tubes in automotive radiators has been developed. The material is an age hardening alloy containing Mg, Si, Cu, and Mn. Titanium is added for corrosion protection. The post-braze strength of the material is dependent on the cooling rate after brazing. With 1°C/s cooling rate between 400 and 200°C, the Rp0.2 will be about 75 MPa. The corrosion resistance of the material is excellent. It is more noble than standard fin materials and will be protected by sacrificial action. Any attack in the material will be forced into a lamellar mode due to the Ti addition.

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.