Refinement of Microstructures for Aluminum Piston through Ultrasonic Melt Treatment

초음파 용탕처리를 이용한 알루미늄 피스톤의 조직 미세화

Lee, Sang-Hwa;Jung, Jae-Gil;Lee, Jung-Moo;Cho, Young-Hee;Yoon, Woon-Ha;Ahn, Yong-Sik;Yun, Dong-Chun;Lee, Jeong-Keun;Ryu, Kwan-Ho

  • Received : 2015.12.16
  • Accepted : 2016.02.12
  • Published : 2016.04.30


The effects of ultrasonic melt treatment on the microstructures of aluminum piston were examined at five observation parts having different cooling rates. The microstructure of aluminum piston consisted of primary Si, eutectic Si, and various types of intermetallic compounds. Regardless of cooling rate, the ultrasonic melt treatment transformed dendritic eutectic cells to equiaxed eutectic cells and it decreased the sizes of eutectic Si and intermetallic compounds that exist at eutectic cell boundaries. In the absence of ultrasonic treatment, coarse primary Si particles were severely segregated and its size was increased with decreasing the cooling rate. The ultrasonic treatment decreased the size of primary Si particles from $25.5{\sim}31.0{\mu}m$ to $17.6{\sim}23.1{\mu}m$, depending on the cooling rate. In the presence of ultrasonic treatment, relatively fine primary Si particles were homogeneously distributed throughout the piston. In addition, the ultrasonic treatment increased the population density and area fraction of fine primary Si particles.


Aluminum;Piston;Ultrasonic;Microstructure;Primary Si


  1. N. Belov, D. Eskin and N. Avxentieva, Acta Mater., "Constituent phase diagrams of the Al-Cu-Fe-Mg-Ni-Si system and their application to the analysis of aluminium piston alloys", 53 (2005) 4709-4722.
  2. Park JY, Lee JS and Ra HY, J. Korea foundry society, "Simultaneous refinement of primary and eutectic Si in hypereutectic Al-Si alloys", 15 (1995) 262-271.
  3. R. Gholizadeh and S.G. Shabestari, Metall. Mater. Trans. A, "Investigation of the effects of Ni, Fe, and Mn on the formation of complex intermetallic compounds in Al-Si-Cu-Mg-Ni alloys", 42A (2011) 3447-3458.
  4. Y. Yang, K. Yu, Y. Li, D. Zhao and X. Liu, Mater. Des., "Evolution of nickel-rich phases in Al-Si-Cu-Ni-Mg piston alloys with different Cu additions", 33 (2012) 220-225.
  5. Y. Li, Y. Wu, Z. Qian and X. Liu, Mater. Sci. Eng. A, "Effect of co-addition of RE, Fe and Mn on the microstructure and performance of A390 alloy", 527 (2009) 146-149.
  6. A.J. Moffat, S. Barnes, B.G. Mellor and P.A.S. Reed, Inter. J. Fatigue, "The effect of silicon content on long crack fatigue behaviour of aluminium-silicon piston alloy at elevated temperatures", 27 (2005) 1564-1570.
  7. M.M. Haque and M.A. Maleque, J. Mater. Proc. Tech., "Effect of process variables on structure and properties of aluminiumsilicon piston alloy", 77 (1998) 122-128.
  8. S. Manasijevi , S. Markovi , Z. A imovi -Pavlovi , K. Rai and R. Radisa, Mater. Tech., "Effect of heat treatment on the microstructure and mechanical properties of piston alloys", 47 (2013) 585-591.
  9. H. Xu, Q. Han and T.T. Meek, Mater. Sci. Eng. A, "Effects of ultrasonic vibration on degassing of aluminum alloys", 473 (2008) 96-104.
  10. S. Zhang, Y. Zhao, X. Cheng, G. Chen and Q. Dai, J. Alloys Comp., "High-energy ultrasonic field effects on the microstructure and mechanical behaviors of A356 alloy", 470 (2009) 168-172.
  11. A. Das and H.R. Kotadia, Mater. Chem. Phys., "Effect of high-intensity ultrasonic irradiation on the modification of solidification microstructure in a Si-rich hypoeutectic Al-Si alloy", 125 (2011) 853-859.
  12. H.R. Kotadia and A. Das, J. Alloys Comp., "Modification of solidification microstructure in hypo- and hyper-eutectic Al-Si alloys under high-intensity ultrasonic irradiation", 620 (2015) 1-4.
  13. H. Puga, J. Barbosa, S. Costa, S. Ribeiro, A.M.P. Pinto and M. Prokic, Mater. Sci. Eng. A, "Influence of indirect ultrasonic vibration on the microstructure and mechanical behavior of Al-Si-Cu alloy", 560 (2013) 589-595.
  14. Cho YH, Lee JM, Yoon WH and Jung JG, Mater. Sci. Forum, "Influence of ultrasonic treatment on the microstructure of hypereutectic Al-17 wt% Si alloys", 794-796 (2014) 89-94.
  15. W. Khalifa, S. El-Hadad and Y. Tsunekawa, Metall. Mater. Trans. A, "Microstructure and wear behavior of solidification sonoprocessed B390 hypereutectic Al-Si alloy", 44A (2013) 5817-5824.
  16. Jung JG, Lee SH, Lee JM, Cho YH, Kim SH and Yoon WH, Mater. Sci. Eng. A, "Improved mechanical properties of neareutectic Al-Si piston alloy through ultrasonic melt treatment", under review.
  17. G. Zhang, J. Zhang, B. Li and W. Cai, Mater. Sci. Eng. A, "Double-stage hardening behavior and fracture characteristics of a heavily alloyed Al-Si piston alloy during low-cycle fatigue loading", 561 (2013) 26-33.
  18. N. Saunders and A.P. Miodownik, "CALPHAD", Elsevier, Oxford (1998).


Supported by : 국가과학기술연구회, 한국기계연구원