| The deformation behaviors of LD7 Aluminum alloy at hot temperature have been studied by isothermal compression. With the help of regression analysis, the effects on flow stress of LD7 Aluminum alloy were explored including different strain rate and deformation temperature, the flow stress equations were built. The relationship between different deformation conditions and microstructure were discussed using optical microscopy, dynamic recovery and dynamic recrystallization were deemed to the restoration mechanisms of the alloy during hot deformation. The theory of processing maps was applied in optimizing the forging processes of LD7 Aluminum alloy. The optimum forging processes are: the starting temperature of forging is 420-450℃, the final temperature is 350-380℃, the region of 250-320℃is the warm forging section; the starting strain rate should be less than 0.1s-1 , the final strain rate should be less than 0.0316 s-1; the final strain should be less than 3% or more than 15% in order to avoid the critical strain.By the means of tensile behavior experiment, the optical microscopy, scanning electron microscopy and transmission electron microscopy and so on, the mechanical properties and microstructure at different holding times, holding temperatures, aging times, and aging temperatures are studied, as well as the interrelations among the mechanical properties , microstructure and heat treatment conditions, with the solid solution ageing strengthening theory, the heat treatment processes of LD7 Aluminum alloy were optimized. The best heat treatment regime is as follows: solution temperature is 535℃solution time is 7 hours, aging temperature is 198-202℃, aging time is nine hours.
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