摘要
采用氟盐法和对掺法成功制备了Al-5Ti-1B-4Sr中间合金,采用X射线衍射(XRD)和扫描电镜(SEM)分析了Al-5Ti-1B-4Sr中间合金的组织及相组成。通过改变Al-5Ti-1B-4Sr中间合金细化变质保温时间,采用微观组织分析和宏观组织分析方法,研究了Al-5Ti-1B-4Sr中间合金对Al-8Si亚共晶铝硅同时细化和变质的效果。研究结果表明,Al-5Ti-1B-4Sr中间合金中含有Al_3Ti相、TiB_2相和Al_4Sr相,Al-5Ti-1B-4Sr中间合金对亚共晶铝硅合金有良好的同时细化变质效果。Al-5Ti-1B-4Sr中间合金可使共晶硅从针状或板片状形貌转变为纤维状或块状。与未变质试样相比,细化变质时间为10 min时,Al-8Si合金中针状或板片状共晶硅显著减少;变质时间超过20 min时,看不到针状或板片状共晶硅存在;当变质时间达到80 min时,部分针状或板片状共晶硅再次出现。随着Al-5Ti-1B-4Sr细化变质保温时间的变化,α-Al的二次枝晶臂间距和共晶团尺寸先减小后增大,细化变质保温时间为30 min时效果最好。Al-5Ti-1B-4Sr中间合金对亚共晶铝硅合金细化变质的孕育期为10~20 min,衰退期为60 min。
The Al-5Ti-1B-4Sr master alloy was prepared successfully by complex halide salts and direct reaction with molten aluminum methods. The microstructure was observed and analyzed by X-ray diffraction（ XRD） and scanning electron microscope（ SEM）.The effect of simultaneous refinement and modification of Al-5Ti-1B-4Sr master alloy on Al-8Si alloy was studied by microstructure and macrostructure analysis with various addition and holding time. The experimental results showed that the Al-5Ti-1B-4Sr master alloy contained Al_3Ti,TiB_2 and Al_4Sr phases,which had a good effect of simultaneous refinement and modification on Al-8Si alloy. The eutectic Si was changed from needle-like or flaky to fibrous or bulky. When the refining and modifying time was 10 min,the needle-like or flaky eutectic Si in Al-8Si alloy became less than that in unmodified Al-8Si alloy. When the refining and modifying time was longer than 20 min and shorter than 80 min,the needle-like or flaky eutectic Si in Al-8Si vanished. When the refining and modifying time was longer than 80 min,the needle-like or flaky eutectic Si in Al-8Si appeared again. The second dendrite arm space（ SDAS） and eutectic cell size decreased firstly and then increased with holding time increasing. The refinement and modification efficiency was best when the holding time was 30 min. The refinement and modification of Al-5Ti-1B-4Sr master alloy on Al-8Si alloy had a 10 - 20 min incubation stage and faded more than 60 min.
作者
王宝山
冯义成
郭育阳
王丽萍
郭二军
姜文勇
Wang Baoshan Feng Yicheng Guo Yuyang Wang Liping Guo Erjun Jiang Wenyong(Engineering Training Center, Harbin University of Science and Technology, Harbin 150040, China School of Materials Science and Engineering, Harbin University of Science and Technology, Harbin 150040, China)
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2017年第10期1082-1086,共5页
Chinese Journal of Rare Metals
基金
黑龙江省自然科学基金项目(ZD2016011)资助
关键词
细化剂
变质剂
中间合金
亚共晶铝硅合金
refinement
modification
master alloy
hypoeutectic Al-Si alloy
作者简介
王宝山（1961-），男，黑龙江哈尔滨人，学士，实验师，研究方向：高性能铝合金，E—mail：1324664896@qq．com.
通信作者：冯义成，副教授，电话：045l一86392518，E-mail：fyc7806067@163．com.
