Effect of ultrasonic power and casting speed on solidification structure of 7050 aluminum alloy ingot in ultrasonic field

Abstract

With the experiment and finite element simulation, the influences of power ultrasonic on the solidification structure of 7050 aluminum alloy ingot in semi-continuous casting were researched, and the effects of casting speed on solidification structure in ultrasonic field were also analyzed. The experiment and simulation results show that the solidification structure of the ingot is homogeneously distributed, and its grain size is obviously refined at ultrasonic power of 240 W. The average grain sizes, which can be seen from the Leica microscope, are less than 100 μm. When the casting speed is 45–50 mm/min, the best grain refinement is obtained.

Keywords

7050 aluminum alloy / ultrasonic power / casting speed / semi-continuous casting / solidification structure

References

[1] ZhangL., ShenH.-f., RongY.-m., HuanT.-you.. Numerical simulation on solidification and thermal stress of continuous casting billet in mold based on meshless methods [J]. Materials Science and Engineering A, 2007, 466(1/2): 71-78

[2] LeQ.-c., GuoS.-j., ZhaoZ.-h., CuiJ.-z., ZhangX.-jian.. Numerical simulation of electromagnetic DC casting of magnesium alloys [J]. Journal of Materials Processing Technology, 2007, 183(2/3): 194-201

[3] ZhangH. T., NagaumibH., YuboZ., CuiJ. Z.. Coupled modeling of electromagnetic field, fluid flow, heat transfer and solidification during low frequency electromagnetic casting of 7XXX aluminum alloys: Part I. Development of a mathematical model and comparison with experimental results [J]. Materials Science and Engineering A, 2007, 448(1/2): 189-203

[4] ZhangH. T., NagaumibH., CuiJ. Z.. Coupled modeling of electromagnetic field, fluid flow, heat transfer and solidification during low frequency electromagnetic casting of 7XXX aluminum alloys: Part II. The effects of electromagnetic parameters on casting processes [J]. Materials Science and Engineering A, 2007, 448(1/2): 177-188

[5] VertnikaR., ZaloznikbM., SarlerB.. Solution of transient direct-chill aluminum billet casting problem with simultaneous material and interphase moving boundaries by a meshless method [J]. Engineering Analysis with Boundary Elements, 2006, 30(10): 847-855

[6] DuQ., EskinD. G., KatgermanL.. The effect of ramping casting speed and casting temperature on temperature distribution and melt flow patterns in the sump of a DC cast billet [J]. Materials Science and Engineering A, 2005, 413/414: 144-150

[7] EskinG. I.Ultrasonic treatment of molten aluminum [M], 1985, Moscow, Metallurgiya: 1-10

[8] EskinG. I.Ultrasonic treatment of light alloy melts [M], 1998, Amsterdam, Gordon & Breach: 1-5

[9] PanJ., YoshidaM., SasakiG.. Ultrasonic insert casting of aluminum alloy [J]. Scripta Materialia, 2000, 43(2): 155-159

[10] LiJ. W., MomonoT.. Effect of starting temperature of ultrasonic application on the structure of Al-Cu alloy ingots [J]. Foundry Technology, 2004, 25(4): 248-251

[11] ZhaoZ.-x., MuG.-hua.. Effect of ultrasonic on the structure and properties of casting alloy [J]. Foundry, 1996, 18(3): 21-25

[12] LiY.-l., LiB.-m., LiuY.-t., GaoC.-r., DaiE.-tai.. Effects of high-intensity ultrasonic on structures and properties of Al-Si alloys [J]. The Chinese Journal of Nonferrous Metals, 1999, 9(4): 719-722

[13] LiJ. W., MomonoT., FuY., JiaZ., TayuY.. Effect of ultrasonic stirring on temperature distribution and grain refinement in Al-1.65%Si alloy melt [J]. Transactions of Nonferrous Metals Society of China, 2007, 17(4): 691-697

[14] GaoX.-p., LiX.-t., QieX.-w., WuY.-p., LiX.-m., LiT.-ju.. Effect of ultrasonic field on the structures and mechanical properties of horizontal continuous casting ingots of Al-1%Si alloy [J]. Acta Metallurgica Sinica, 2007, 43(1): 17-22

[15] HuS.-c., MaW.-c., DuL.. Thermal contact conductance at continuous roll-casting interface [J]. Journal of Central South University of Technology, 2007, 14(3): 374-379

[16] RappazM., GandinC. A.. Probabilistic modeling of microstructure formation in solidification processes [J]. Acta Metall, 1993, 41(2): 345-360