过共晶铝硅合金微纳米SiO_2变质剂的制备与细化作用  

Effects of Micro-nano SiO2 on Refinement of Primary Si in Hypereutectic Al-Si Alloy

作　　者：王振 李成栋[1] 王鹰 矫鹏飞 WANG Zhen;LI Chengdong;WANG Ying;JIAO Pengfei(College of Materials Science and Engineering,Qingdao University of Science and Technology,Qingdao 266042,China)

机构地区：[1]青岛科技大学材料科学与工程学院,山东青岛266042

出　　处：《青岛科技大学学报（自然科学版）》2020年第6期39-43,共5页Journal of Qingdao University of Science and Technology:Natural Science Edition

基　　金：国家自然科学基金项目(51672145).

摘　　要：未经处理的过共晶铝硅合金中存在大片状的初晶硅和细针丝状共晶硅,不仅降低了其力学性能,还会对合金的切削加工性能造成负面影响。利用溶胶凝胶法制备了微纳米SiO_2颗粒,并以此为变质剂对Al-24Si合金进行了细化处理,取得了明显的细化效果。通过金相显微镜(OM)观察,X射线衍射仪(XRD)分析及能量分散谱仪(EDS)分析,探究了SiO_2变质剂对Al-24Si合金微观组织的影响。结果表明,SiO_2能够细化初晶硅。当铝硅合金中SiO_2变质剂的添加量为0.6%(质量分数)时,SiO_2对铝硅合金的变质效果最好,能将Al-24Si合金中的初晶硅平均尺寸细化至60μm以下。The presence of large-sized primary crystal silicon and fine needle-like eutectic silicon in the untreated hypereutectic Al-Si alloy not only reduces the mechanical properties,but also negatively affects the cutting performance of the alloy.In this paper,micro-nano SiO2 particles were prepared by sol-gel method,and the Al-24Si alloy was refined by using this as a modifier,and the refinement effect was obtained.The effects of SiO2 modifier on the microstructure of Al-24Si alloy were investigated by metallographic microscope(OM)observation,X-ray diffraction(XRD)analysis and energy dispersive spectroscopy(EDS)analysis.The results show that SiO2 can refine primary silicon.When the addition amount of the SiO2 modifier in the aluminum-silicon alloy is 0.6%,SiO2 has the best effect on the modification of the aluminum-silicon alloy,and the average size of the primary silicon in the Al-24Si alloy can be refined to 60μm or less.

关 键 词：过共晶铝硅合金 初晶硅 SiO_2变质剂 

分 类 号：TG13[一般工业技术—材料科学与工程]