稀土磷复合变质剂对Al-20%Si合金的细化处理研究  

Refinement of Al-20%Si Alloy by AlTiCREP Compound Modifier

作　　者：林益雄 王连登[1,2] 杜安栋[2] 王沁峰 王火生 张拓[2] 黄街华 LIN Yi-xiong;WANG Lian-deng;DU An-dong;WANG Qin-feng;WANG Huo-sheng;ZHANG Tuo;HUANG Jie-hua(College of Mechanical Engineering,Fuzhou University,Fuzhou 350108,Fujian,China;China Academy of Machinery Sciences and Technology(Jiangle)Institute of Semi-Solid Metal Technology,Jiangle 353300,Fujian,China;School of Mechanical and Energy Engineering,Jimei University,Xiamen 361021,Fujian,China;School of Material Science and Engineering,Fujian University of Technology,Fuzhou 35000,Fujian,China)

机构地区：[1]福州大学机械工程及自动化学院,福建福州350108 [2]机械科学研究总院(将乐)半固态技术研究所,福建将乐353300 [3]集美大学机械与能源工程学院,福建厦门361021 [4]福建工程学院机电及自动化工程系,福建福州350108

出　　处：《铸造》2020年第10期1065-1071,共7页Foundry

基　　金：3500吨高效智能挤压成形装备及工艺示范应用(2019ZX04029001);福建省对外合作产业化项目(201911003)。

摘　　要：采用EPMA、XRD与DSC等分析手段,对制得的AlTiCREP(含2%P)进行物相分析,研究不同P(以AlTiCREP形式加入)添加量、熔体处理温度及保温时间对Al-20%Si初生硅的变质效果的影响,并探讨其细化机理。结果表明:制得的AlTiCREP中间合金含有TiAl3、TiC、AlP及稀土复合相;经AlTiCREP中间合金变质的初生硅颗粒明显细化且较圆整。添加0.03%AlTiCREP的变质效果最佳,初生Si尺寸细化至26.40μm,相对AlTiCRE细化的晶粒尺寸减小了10.8%,这归因于变质剂中的TiC在硅的作用下易于反应形成的Al4C3。该相可作为AlP的基底,在细化过程形成的Al4C3·AlP为初晶硅提供更多的形核质点,提高了AlP变质效果。最佳熔体处理温度为800℃,细化时效长达120 min。The microstructure of AlTiCREP(2%P) master alloys were detected by EPMA, XRD and DSC. The modification effect of the master alloy on the primary Si of the Al-20%Si alloy and the related mechanism were discussed. The results show that AlTiCREP master alloy contains TiC, AlP, TiAl3 and rare earth compound phase;after modification by AlTiCREP master alloy, the primary Si phase particles were significantly refined and rounded. Adding 0.03 wt.% AlTiCREP has the best modification effect. The primary Si size is refined to 26.40 μm, and the grain size is reduced by 10.8% compared with that refined by ALTICRE. The modification and refinement mechanism of AlTiCREP master alloy lied in that the TiC particles could be dissolved into the melt and generated the Al4C3. Al4C3 as a nucleation site of AlP, increases the refining effect of AlP on the primary silicon. The optimum melt treatment temperature is 800 ℃, and effective time reaches 120 minutes.

关 键 词：Al-Ti-C-RE-P 热力学分析 AL-20%SI合金 变质处理 初晶硅 

分 类 号：TG146.21[一般工业技术—材料科学与工程]