李明,李元东

• 1:河西学院物理与机电工程学院
• 2:河西学院先进材料成形技术研究所
• 3:兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室

摘要(Abstract)：

采用自孕育法制备A356铝合金半固态浆料,通过光学显微镜、扫描电镜、能谱及电子探针研究浆料在连续冷却、等温保温及随炉冷却过程中的组织及成分变化。结果表明:采用自孕育法能够制备出初生α-Al晶粒细小且分布均匀的非枝晶半固态浆料;浆料在连续冷却过程中,初生α-Al晶粒逐渐长大并圆整,固相体积分数逐渐增大。浆料等温保温初期初生α-Al晶粒逐渐长大并圆整,晶粒长大速率符合D_t~3-D_0~3=Kt动力学方程;过长的保温时间会使晶粒合并而恶化组织。随炉冷却过程中较慢的冷却速率使剩余液相无法独立形核,浆料剩余液相主要通过初生α-Al晶粒稳定生长以及共晶反应而实现凝固;随着随炉冷却时间的延长,Mg完全扩散至晶内,晶内Si含量逐渐增加。

关键词(KeyWords)： A356铝合金;自孕育法;连续冷却;等温保温;随炉冷却;组织演变

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51464031);; 河西学院青年基金(QN2018011)

作者(Author): 李明,李元东

DOI: 10.13289/j.issn.1009-6264.2020-0032

参考文献(References)：

• [1] Flemings M C.Behavior of metal alloys in the semi-solid state[J].Metallurgical Transactions B,1991,22(3):957-981.
• [2] 罗守靖,姜永正,李远发,等.重新认识半固态金属加工技术[J].特种铸造及有色合金,2012,32(7):603-607.LUO Shou-jing,JIANG Yong-zheng,LI Yuan-fa,et al.Recognition of semi-solid metal forming technologies[J].Special Casting and Nonferrous Alloy,2012,32(7):603-607.
• [3] Eskin D G,Katgerman S L.Mechanical properties in the semi-solid state and hot tearing of aluminum alloys[J].Progress in Materials Science,2004,49(5):629-711.
• [4] 徐骏,张志峰.半固态加工技术的最新进展[J].哈尔滨理工大学学报,2013,18(2):1-6.XU Jun,ZHANG Zhi-feng.Research progress of semisolid processing technology[J].Journal of Harbing University of Science and Technology,2013,18(2):1-6.
• [5] Zhao J W,Wu S S.Microstructure and mechanical properties of rheo-diecasted A390 alloy[J].Transactions of Nonferrous Metals Society of China,2010,20 (S3):754-757.
• [6] Yuck J A,Martinez R A,Flemings M C.Development of the semi-solid rheocasting (SSR) process[C]//Proc of 7th Int on Semi-Solid Process of Alloys and Composites,Tsukuba Japan,2002:659-664.
• [7] Pan Q Y,Findon M,Apelian D.The continuous rheoconversion process(CRP)[C]//8th International Conference on Semi-Solid Process of Alloys and Composites,2004,Limassol,Cyprus.
• [8] Kaudmann H,Mundi A,Potzinger R,et al.An update on the new rheo-casting-development work for Al and Mg alloys[J].Die Casting Engineer,2002(4):16-19.
• [9] Chen Z Z,Mao W M,Wu Z C.Influence of serpentine channel pouring process parameters on semi-solid A356 aluminum alloy slurry[J].Transactions of Nonferrous Metals Society of China,2011,21(5):985-990.
• [10] Guan R G,Cao F R,Zhao Z Y,et al.Effects of wavelike sloping plate rheocasting and spheroidisation on microstructures and properties of Al-18%Si-5%Fe alloy[J].The Chinese Journal of Nonferrous Metals,2011,21(9):2084-2090.
• [11] Midson S P.Rheocasting processes for semi-solid casting of aluminum alloy[J].Die Casting Engineer,2006,50(1):48-51.
• [12] Li M,Li Y D,Zheng H Q,et al.Solidification behavior of 6061 wrought aluminum alloy during the rheo-diecasting process with self-inoculation method[J].Transactions of Nonferrous Metals Society of China,2018,28:879-889.
• [13] Manson-Whitton E D,Stone I C,Jones J R,et al.Isothermal grain coarsening of spray formed alloys in the semi-solid state[J].Acta Materialia,2002(50):2517-2535.
• [14] 高义民.金属凝固原理[M].西安:西安交通大学出版社,2010.

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