欢迎登录材料期刊网

材料期刊网

高级检索

采用旋转黏度计测定AlSi10MnMg铝合金熔体的黏度,压铸制备薄壁铝合金铸件,并用高速摄像技术记录分析充型速度,计算流体力学参数Re数和We数来表征薄壁铝合金压铸充型过程中的流动特征,最后采用OM研究其组织。结果表明:旋转黏度计适合于测定非牛顿流体铝合金熔体系统;铝合金熔体以层流、充型前端液面自由表面破碎成细小液滴的形式高速填充薄壁流动试样型腔;浇注温度升高,黏度减小,充型时间、充型速度和充型距离增加,气孔增加,α(Al)晶粒由块状向球状、蔷薇状转变,晶粒尺寸分布越来越均匀;沿充型流动长度方向,气孔先增加后减少,晶粒尺寸分布变化不大;铸件中心位置晶粒尺寸、α(Al)相含量大于型壁边界位置。

The viscosity of AlSi10MnMg aluminum alloy was measured by a rotational viscometer. The thin-wall fluidity samples were prepared by high pressure die casting. The filling velocity was recorded and analyzed by high speed camera system. Re and We were calculated to represent the flow characteristics during the filling process. OM was employed to study the microstructure. The results show that the rotational viscometer is suitable for the non-Newtonian fluid aluminum alloy melt system. The aluminum alloy melt fills the cavity of thin-wall fluidity specimen at a high-speed in the form of laminar flow when the melt free surface is broken into small droplets. While the viscosity decreases with the pouring temperature increasing, the filling fluidity time, velocity and length increase. High temperature increases porosity and causes that the morphology ofα(Al) grain changes from massive to spherical and rose-shaped. The grains become uniform with the temperature increasing. The porosity decreases firstly and then increases, but the change of grain size distribution is undetectable along fluidity length. Both the grain size andα(Al) phase in the center are higher than those in the boundary.

参考文献

[1] Alan I. Taub;Paul E. Krajewski;Alan A. Luo;John N. Owens .The Evolution of Technology for Materials Processing over the Last 50 Years: The Automotive Example[J].JOM,2007(2):48-57.
[2] ZHANG Li-qiang;LI Luo-xing;ZHU Bi-wu .Simulation study on the low pressure die casting(LPDC)process for thin-walled aluminum alloy casting with permanent mold[J].Materials and Manufacturing Processes,2009,24(12):1349-1353.
[3] FRANKE R;DRAGULIN D;ZOVI A;CASAROTTO F.Progress in ductile aluminum high pressure die casting alloys for the automotive industry[J].Metallurgia Italiana,2007(05):21-26.
[4] RAVI K R;PILLAI R M;AMARANATHAN K R;PAI B C CHAKRABORTY M .Fluidity of aluminum alloys and composite:A review[J].Journal of Alloys and Compounds,2008,456(02):201-210.
[5] SABATINO M D;ARNBERG L .A review on the fluidity of al based alloys[J].Metallurgical Science and Technology,2004,22(01):9-15.
[6] 传海军,黄晓锋,毛祖莉,田载友.压铸工艺对铝合金组织性能影响的研究进展[J].新技术新工艺,2007(10):21-24.
[7] 纪莲清,郭长江,熊守美,Masayuki Murakami,Yoshihide Matsumoto,Shingo Ikeda,刘坤.超低速压铸慢压射速度下ADC12铝合金的显微组织和性能[J].中南大学学报(自然科学版),2010(03):977-981.
[8] 谭建波,李增民,郭莉军,樊金玲,侯文杰,胡映勇,邢书明.初始组织特征对充型过程中初生相演变的影响[J].中国有色金属学报,2009(07):1216-1223.
[9] 朱必武,李落星,刘筱,王水平,张立强.薄壁铝合金压铸充型沿程的组织与力学性能[J].中国有色金属学报,2012(08):2163-2173.
[10] Dinsdale AT;Quested PN .The viscosity of aluminium and its alloys - A review of data and models[J].Journal of Materials Science,2004(24):7221-7228.
[11] BROOKS R F;DINSDALE A T;QUESTED P N .The measurement of viscosity of alloys-A review of methods,date and models[J].Measurement Science and Technology,2005,16(02):354-362.
[12] QI Y;CAGIN T;KIMURA Y;GODDARD W AⅢ .Viscosities of liquid metal alloys from nonequilibrium molecular dynamics[J].JOURNAL OF COMPUTER-AIDED MATERIALS DESIGN,2001,8(2/3):233-243.
[13] MALIK M M;LAMBOTTE G;HAMED M S;CHARTRAND P,SHANKAR S.How to measure viscosity of liquid aluminum alloys[M].Orlando:TMS,2007:43-50.
[14] VARSANI V;FAN Z.Non-newtonian behavior of liquid metals[M].Orlando:TMS,2007:67-76.
[15] Malik, M.M.;Jeyakumar, M.;Hamed, M.S.;Walker, M.J.;Shankar, S. .Rotational rheometry of liquid metal systems: Measurement geometry selection and flow curve analysis[J].Journal of Non-Newtonian Fluid Mechanics,2010(13/14):733-742.
[16] 杨裕国.铝压铸成型及质量控制[M].北京:化学工业出版社,2009:55-57.
[17] HAN Qing-you;XU Han-bing .Fluidity of alloys under high pressure die casting condition[J].Scripta Materialia,2005,53(01):7-10.
[18] SAHOO K L;SIVARAMAKRISHNAN C S .Some studies on Al-8.3Fe-0.8V-0.9Si alloy for near net shape casting[J].Journal of Material Process and Technology,2003,135(2/3):253-275.
[19] REIKHER A;BARKHUDAROV.Casting:An analytical approach[M].London:Springer-Verlag London Limited,2007:21-22.
[20] 朱爱民.流体力学基础[M].北京:中国计量出版社,2004:35-36.
[21] MANZELLO S L;YANG J C .The influence of liquid pool temperature on the critical impact Weber number for splashing[J].Physics of Fluids,2003,15(01):257-260.
[22] OMID LASHKARI;LU YAO;STEVE COCKCROFT .X-Ray Microtomographic Characterization of Porosity in Aluminum Alloy A356[J].Metallurgical and Materials Transactions, A. Physical Metallurgy and Materials Science,2009(4):991-999.
[23] ZHANG L Y;JIANG Y H;MA Z;SHAN S F JIA Y Z FAN C Z WANG W K .Effect of cooling rate on solidified microstructure and mechanical properties of aluminum-A356 alloy[J].Journal of Materials Processing Technology,2008,207(1/3):107-111.
[24] ZHANG Ming,ZHANG Wei-wen,ZHAO Hai-dong,ZHANG Da-tong,LI Yuan-yuan.Effect of pressure on microstructures and mechanical properties of Al-Cu-based alloy prepared by squeeze casting[J].中国有色金属学会会刊(英文版),2007(03):496-501.
上一张 下一张
上一张 下一张
计量
  • 下载量()
  • 访问量()
文章评分
  • 您的评分:
  • 1
    0%
  • 2
    0%
  • 3
    0%
  • 4
    0%
  • 5
    0%