The slurry stability time of semi-solid slurry prepared is one of the key factors of whether the semi-solid rheomolding can be industrialized.The effects of holding time on microstructure of semi-solid ZL117 alloy slurry are discussed.Experiment indicates that with extending holding time

although the solid volume fraction is little affected

average particle degree of primary Si in the slurry is obviously increased.Meanwhile

shape of primary Si becomes more and more sharp before 15 min

and shape is little changed due to the aggregation of the primary Si after 15 min.