Microstructure Evolution of 7075 Al Alloy During Semi-solid Isothermal Heat Treatment
The microstructure evolution of 7075 aluminum alloy during different semi-solid isothermal heat treatment was researched,the proper isothermal heat treatment process was gained.The results show that,under the same holding time,grain size and spheroidization increases with the increase of isothermal temperature;at the same heat treatment temperature,grain size increases with the increase of holding time,grain roundness firstly decreases and then increases.The grain size and roundness is gained through software Image Proplus6.0,the relationship among grain size,holding time and roundness is obtained.Then these data are analyzed through data processing software origin7.5 fitting,the curve between grain size(diameter) and holding time is obtained.