Effects of different holding temperatures on microstrucural evolution of AlSi7Mg alloy in permanent mold were observed.Morphology evolution of primary α phase in the alloy was observed by holding at 600～650 ℃ for 30 min.The results show that

while holding at 605～650 ℃

with decreasing in holding temperature

the primary α phase is gradually converted from developed dendrite into the rosette dendrite and then into particle crystal.Fine and uniform distributed particle phase in the alloy can be formed by holding at 605 ℃ for 30min.Furthermore

the primary α phase can be involved into rosette crystal.In addition

the primary α phase is converted from irregular dendrite to uniform equaixed particle crystal then to rosette structure at 605 ℃ with holding time from 10 min to 60 min.