采用自孕育铸造法制备AM60镁合金半固态坯料,研究导流器参数对半固态组织的影响规律及组织形成机理.结果表明:导流器能有效促进合金组织由树枝晶向等轴晶及颗粒状晶的转变；熔体处理温度和孕育剂加入量一定时,导流器的相关参数,如角度、长度、温度、混合段的凹槽宽度,均影响合金的传热及流动,进而影响其凝固组织；在导流器角度为30°～45°、长度为500 mm、混合段凹槽宽度为50 mm、且通水冷却时可以获得细小颗粒状或蔷薇状的半固态坯料,初生α-Mg的平均晶粒尺寸为37.5μm;减小导流器出口宽度有利于增强液体紊流,促进晶粒均匀分布;导流器促进了熔体非均质形核及激冷晶的形成,增强了晶粒增殖；熔体对流使合金的温度场和浓度场更均匀,晶粒生长以颗粒状生长、蔷薇晶根部颈缩熔断和磨圆熟化机制为主.
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