الفهرس 
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Abstract
The results have shown that age hardening peaks were formed at different ageing temperatures in both thermal and thermomechanical processes. In each case an initial period of linear hardening was recorded, after which the rate of hardening decreased then increased again.
Also, the results indicate that the;2024 alloy exhibits better results compared to the 2017 one under
? all experimental conditions, i.e, the time required to
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if attain optimum results for 2024 alloy is shorter than
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i; that required for 2017 one. At the same time the peak hardness values of the 2024 alloy is greater than that of the 2017.
In addition, both alloys exhibit a ITS: :^e L:.”~e characteristics ;~ :5~,= iLe r.-z •. i e. : ~-’e”2~- -.- 3__ ageing temperatures. s
As the ageing temperature is increased the value of peak strength increased and the time required to attain it is reduced. Also, it is seen that when the yield strength increase’s, the ductility (as measured by percentage of elongation to fracture) decreases contin-ously up to the peak strength and then remains constant.
In the: case of thermomechanical treatment, it can ba seen that amount of deformation before ageing very