The 2024 wrought aluminum alloy ingots prepared by self-inoculation method were remelted partially by the thermal simulator

and effects of remelting temperature on the microstructure of the remelted isothermal holding and without holding ingots were investigated.The results show that nondendrite microstructure can be observed in slurry prepared by self-inoculation method.There exist amounts of equiaxed dendrites and a little underdeveloped dendrites without holding

while primary particles are spherical and distributed homogeneously in the matrix without liquid wrapping with isothermal temperature increase.Mergence and Ostwald ripening are the main mechanism of primary phase and secondary phase in the ingots.Formation of remelting liquid phase is in form of thin film

then more liquid phase grows gradually into a small area

which provides conditions for secondary solidification in subsequent work.The mechanism of secondary phase is dependent on growth of primary phase or independent nucleation and spherical solid grains.The end of the eutectic reaction is mean to the completion of the solidification process.