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采用转棒诱导形核法制备A356铝合金半固态浆料,研究保温时间对半固态浆料组织的影响.结果表明,随着保温时间延长,初生α-Al相等效直径不断增大,但初生α-Al的形状因子先降低后升高,符合Oswald长大机制.在保温1 min时初生α-Al相的等效直径最小,约为54μm,形状因子为0.89,单位面积内的颗粒数最多约为175/mm2;在保温5 min时,初生α-Al相形状因子最小,为0.83,其等效直径约为74 μm,单位面积内的颗粒数约为130/mm2;保温20 min时,初生α-Al的形状因子最大,为0.97,单位面积内的颗粒数约为70/mm2.“,”The rotating-rod induced nucleation (RRIN) was adopted to fabricate the semi-solid slurry of A356 alloy,and influence of holding time on the microstructure of A356 aluminum alloy semi-solid slurry was investigated.The results show that,with the increase of holding time,the primary phase size is increased gradually,however,the shape factor of the primary α-Al is decreased firstly and then increased,which follows the Oswald ripening mechanism.With holding for 1 min,the equivalent diameter of the primary phase is about 54 μm with shape factor of 0.89,while the number of particles per unit area is about 175/mm2.With the holding time of 5 min,the primary α-Al shape factor is 0.83,and its equivalent diameter reaches about 74 μm,and number of particles per unit area is about 130/mm2.However,the shape factor reaches the largest with the holding time of 20 min,as much as 0.97,and the number of particles per unit area is about 70/mm2.