Table 5: Basic temper designation of Al alloys [2, 11, 12].

Temper Treatment Use F Fabricated The products fabricated by casting, hot working, cold working processes without control over elevated temperature treatment or work hardening is used. O Annealed The castings which are annealed to enhance ductility and dimensional stability. The wrought semis which are annealed to obtain lowest strength temper. H Strain hardened The wrought products only which are work hardened with or without supplementary elevated temperature treatments to get desired ductility at lower strength. The H is always followed by two or greater than two digits. W Solution treated The alloys which age at room temperature after solution heat-treatment to produce unstable temper. This designation is proper only when the time of the aging is indicated. T Stable tempers The products which show stable tempers after heat treatment with or without supplementary work-hardening. The T is always followed by one or several digits.