【摘要】 在Couette型同轴双桶流变仪上对半固态AZ91D合金浆料的流变性能以及组织进行了研究 ,结果表明 :连续冷却条件下 ,半固态AZ91D合金浆料的表观粘度与冷却速率有很大的关系 ,低冷速下的表观粘度低于高冷速下的表观粘度 ;连续冷却条件下 ,半固态AZ91D合金浆料的表观粘度还受剪切速率的影响 ,随剪切速率的增高 ,浆料的表观粘度降低 ;连续搅拌半固态AZ91D合金浆料的组织与冷却速率和剪切速率有关 ,降低冷却速率和增大剪切速率都有利于固相颗粒的球化更多还原

【Abstract】 The rheological behavior and microstructure of semi-solid AZ91D when continuously cooled is studied using a Couette type viscometer in the present paper. The results show that the apparent viscosity of semi-solid AZ91D increases with the cooling rate increasing when continuously cooled and mechanical stirred and the empiric relation of the apparent viscosity with the cooling rate and solid fraction at shearing rate 93.7s^-1 is expressed as , that the apparent viscosity of semi-solid AZ91D increases with the shearing rate increasing when continuously cooled and mechanical stirred and the empiric relation of the apparent viscosity with the shearing rate and solid fraction at cooling rate 4 ℃/min is showed as, that the cooling rate and shearing rate have important effect on the microstructure of the semi-solid AZ91D alloy slurry when continuously cooled and mechanical stirred, and decreasing the cooling rate and increasing the shearing rate are favorable to the non-dendritic evolution of the primary grains.更多还原