P-LaCe复合变质对过共晶Al-25%Si合金的变质效果  

Modification Effect of P-LaCe Composite Modification on Hypereutectic Al-25%Si Alloy

作　　者：何红宇 石为喜[1] 滕海琳 林业达 茆俊 仇正 HE Hongyu;SHI Weixi;TENG Hailin;LIN Yeda;MAO Jun;QIU Zheng(School of Metallurgy and Materials Engineering,Liaoning Institute of Science and Technology,Benxi Liaoning 117004,China)

机构地区：[1]辽宁科技学院冶金与材料工程学院,辽宁本溪117004

出　　处：《辽宁科技学院学报》2023年第6期1-3,77,共4页Journal of Liaoning Institute of Science and Technology

基　　金：2024年辽宁科技学院大学生创新创业训练计划项目;辽宁省教育厅基本科研项目(面上项目)(LJKZ1066).

摘　　要：文章分别采用1.0%LaCe、0.8%P以及1.0%LaCe-0.8%P复合变质对Al-25%Si合金进行变质处理,研究不同变质剂对Al-25%Si合金的变质效果。经变质处理后,Al-25%Si合金中的初晶硅都有着不同程度的细化作用,0.8%P的变质效果为最佳,初晶硅由未变质的粗大的五瓣星状及其他较复杂形状转变为细的多边形状和板片状,平均晶粒尺寸由150μm~200μm细化至30μm~50μm,共晶硅以长针状分布,分布密度明显降低。单纯加1.0%LaCe处理后,合金中初晶硅形态上无变化,平均晶粒尺寸略有减小,共晶硅发生明显变化,从长针状变为颗粒状或短棒状,尺寸大幅减小。P-LaCe复合变质需控制好二者的添加量的配比,否则易产生过变质现象,降低变质效果。力学性能测试结果表明,经变质处理后的Al-25%Si合金的抗拉强度与硬度均不同程度增加,以0.8%P变质后的合金力学性能为最佳,与金相组织细化程度相对应。In this study,composite modification was applied to refine Al-25%Si alloy using 1.0%LaCe,0.8%P,and 1.0%LaCe-0.8%P,respectively.The modification effects of different modifiers were investigated.The results showed that the primary silicon in Al-25%Si alloy exhibits varying degrees of refinement after modification and the modification effect using 0.8%P is the best.The primary silicon transforms from coarse five petal star shape and other complex shapes without modification to fine multilateral and plate shapes,with an average grain size from 150μm-200μm to 30μm-50μm.Eutectic silicon becomes long needle shaped with a significant decrease in its distribution density.After simply adding 1.0%LaCe for treatment,there is no discernable change in the morphology of primary silicon,and the average grain size slightly decreases.However,there is a significant change in the morphology of eutectic silicon,from long needle shape to granular or short rod shape,with a significant decrease in the grain size.P-LaCe composite modification needs to control the amount ratio of the two additives,otherwise it is prone to over modification and thus modification effect reduction.The mechanical properties test results showed that the tensile strength and hardness of Al-25%Si alloy after modification increase by varying degrees.The alloy with 0.8%P modification has the best mechanical properties,corresponding to the degree of refinement of the metallographic structure.

关 键 词：过共晶铝硅合金 LaCe变质 P变质 初晶硅 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG113[金属学及工艺—金属材料]