Aluminium alloys continued

So aluminium alloy is good it resists all the fluids likely to come in contact with it. What about GFRP The strength of GFRP is reduced by up to 20% by continuous immersion in most of the fluids - even salf water - with which it is likely to come into contact but (as we know from fibreglass boats) this drop in strength is not critical, and it occurs without visible corrosion, or loss of section. In fact, GFRP is much more corrosion-resistant, in the normal sense of loss-of-section, than steel. 

Dobatkin, V.I. and Eskin, G.I. Mechanisms of Nondendritic Solidification during Continuous Casting of Aluminium Alloys Ingots. Proc. 2nd Int. Conf. Alum. Alloys, Oct. 1990, Beijing, Int. Acad. Publ., Beijing, 1990, pp. 278-282. 

Figures 3.1-57a and 3.1-57b show typical softening curves for aluminium alloys in three characteristic stages recovery, recrystallization, and grain-growth. In the case of the untreated continuously cast and rolled strip shown in Fig. 3.1-57a, recrystallization will occur at temperatures between about 260 and 290 °C. In Fig. 3.1-57b, recrystallization starts after about half an hour and is complete after about an hour. The...

NapaUcov VN, Cherepok GV, Mahov SV. Continuous casting of aluminium alloys (in Russian). Moscow Intermet Engineering 2006. 328 p. 

With eight series or families, aluminium alloys are very numerous and offer a wide range of compositions, properties and uses. The continuing progress in the metallurgy of... 

Also, whilst on the subject of corrosion it is of interest to note that in Europe the preferred pretreatment employed by the aerospace community is CAA rather than PAA. The CAA produces a much thicker oxide than the American developed PAA treatment, typically about 4 jum as opposed to 0.4/xm. Hence, the CAA treatment offers far better intrinsic corrosion protection for the aluminium alloy. This reason, and the fact that historically the Europeans have developed and established confidence in the CAA pretreatment, has led to the continued use of the CAA process in Europe. 

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