Advertisement

Optimal Stator Design for Oxide Films Shearing Found by Physical Modelling

  • Agnieszka DybalskaEmail author
  • Dmitry G. Eskin
  • Jayesh B. Patel
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)

Abstract

A new technology suggests breaking oxide films into small fragments or particles to play the role of a grain refiner. A high-shear mixer (HSM) with a rotor-stator impeller can produce mechanical breakage. Physical modelling with powders demonstrates the defragmentation potency of HSM. Optimisation methods are considered and a new design of HSM is proposed according to the experimental findings. This design improves the uniformity of mixing in the pseudo-cavern volume and exhibits the dispersion efficiency better than the design previously used. The understanding and development of high shear technology for processing of liquid metals is of great interest to the industry.

Keywords

Liquid metal High shear Rotor-stator Pseudo-cavern Defragmentation Stator design 

Notes

Acknowledgements

Allocation of the equipment in the BCAST (Brunel University London) is highly appreciated. The first author is grateful for Ph.D. study funding from the Institute of Materials and Manufacturing, Brunel University London. The authors would also like to acknowledge Prof. Z. Fan, who initiated this research. The PIV measuring system was provided by the EPSRC Engineering Instrument Pool.

References

  1. 1.
    Green NR, Campbell J (1993) Statistical distributions of fracture strengths of cast A1-7Si-Mg alloy. Mater Sci Eng A 173:261–266CrossRefGoogle Scholar
  2. 2.
    Mi J, Harding RA, Campbell J (2004) Effects of the entrained surface film on the reliability of castings. Metall Mater Trans A 35(9):2893–2902CrossRefGoogle Scholar
  3. 3.
    Nyahumwa C et al (1998) Effect of mold-filling turbulence on fatigue properties of cast aluminum alloys. Paper presented at the 102nd Casting Congress, Atlanta, Georgia, 10–13 May 1998Google Scholar
  4. 4.
    Wang QG, Apelian D, Lados DA (2001) Fatigue behavior of A356-T6 aluminum cast alloys. Part I. Effect of casting defects. J Light Met 1(1):73–84CrossRefGoogle Scholar
  5. 5.
    Fan Z (2011) Epitaxial nucleation and grain refinement. Paper presented at the John Hunt International Symposium, Uxbridge, London, 12–14 Dec 2011Google Scholar
  6. 6.
    Men H, Fan Z (2011) Effects of lattice mismatch on interfacial structures of liquid and solidified Al in contact with hetero-phase substrates: MD simulations. Paper presented at the ICASP–3, Rolduc Abbey, Aachen, The Netherlands, 7–10 June 2011Google Scholar
  7. 7.
    Tzamtzis S, Zhang H, Xia M, Babu NH, Fan Z (2011) Recycling of high grade die casting AM series magnesium scrap with the melt conditioned high pressure die casting (MC-HPDC) process. Mater Sci Eng A 528(6):2664–2669CrossRefGoogle Scholar
  8. 8.
    Li HT et al (2011) Harnessing oxides in liquid metals and alloys. Paper presented at the John Hunt International Symposium, Uxbridge, London, 12–14 December 2011Google Scholar
  9. 9.
    Scamans G et al (2012) Melt conditioned casting of aluminum alloys. Paper presented at ICAA13, Pittsburgh, Pennsylvania, 3–7 June 2012CrossRefGoogle Scholar
  10. 10.
    Li HT, Scamans G, Fan Z (2013) Refinement of the microstructure of an Al-Mg2Si hypereutectic alloy by intensive melt shearing. Mater Sci Forum 765:97–101CrossRefGoogle Scholar
  11. 11.
    Patel J et al (2013) Liquid metal engineering by application of intensive melt shearing. Paper presented at LMPC 2013, Austin, Texas, 22–25 Sept 2013Google Scholar
  12. 12.
    Zuo YB et al (2011) Grain refinement of DC cast magnesium alloys with intensive melt shearing. Paper presented at the ICASP–3, Rolduc Abbey, Aachen, The Netherlands, 7–10 June 2011Google Scholar
  13. 13.
    Li HT, Wang Y, Fan Z (2012) Mechanisms of enhanced heterogeneous nucleation during solidification in binary Al–Mg alloys. Acta Mater 60:1528–1537CrossRefGoogle Scholar
  14. 14.
    Li HT, Xia M, Jarry P, Scamans G, Fan Z (2011) Grain refinement in a AlZnMgCuTi alloy by intensive melt shearing: A multi-step nucleation mechanism. J Cryst Growth 314(1):285–292CrossRefGoogle Scholar
  15. 15.
    Dybalska A (2016) Understanding and development of high shear technology for liquid metals processing. PhD thesis, Brunel UniversityGoogle Scholar
  16. 16.
    Gupta D, Lahiri AK (1996) A water model study of the flow asymmetry inside a continuous slab casting mold. Metall Mater Trans B 27(5):757–764CrossRefGoogle Scholar
  17. 17.
    Xu D, Jones W, Kinzy W, Evans JW (1998) The use of particle image velocimetry in the physical modeling of flow in electromagnetic or direct-chill casting of aluminum: Part I. Development of the physical model. Metall MaterTrans B 29:1281–1288CrossRefGoogle Scholar
  18. 18.
    Zhang L, Yang S, Cai K, Li J, Wan X, Thomas BG (2007) Investigation of fluid flow and steel cleanliness in the continuous casting strand. Metall Mater Trans B 38(1):63–83CrossRefGoogle Scholar
  19. 19.
    Karcz J, Szoplik J (2004) An effect of the eccentric position of the propeller agitator on the mixing time. Chem Pap-Slovak Acad Sci 58(1):9–14Google Scholar
  20. 20.
    Tzanakis I, Lebon GSB, Eskin DG, Pericleous KA (2017) Characterizing the cavitation development and acoustic spectrum in various liquids. Ultrason Sonochem 34:651–662CrossRefGoogle Scholar
  21. 21.
    Raffel M, Willert C, Wereley S, Kompenhans K (2007) Particle imaging velocimetry—a practical guide, 2nd edn. Springer, BerlinGoogle Scholar
  22. 22.
    Adrian RJ, Westerweel J (2011) Particle image velocimetry. Cambridge University Press, CambridgeGoogle Scholar
  23. 23.
    Huang H, Dabiri D, Gharib M (1997) On errors of digital particle image velocimetry. MST 8(12):1427–1440Google Scholar
  24. 24.
    Doucet L, Ascanio G, Tanguy PA (2005) Hydrodynamics characterization of rotor-stator mixer with viscous fluids. Chem Eng Res Des 83(10):1186–1195CrossRefGoogle Scholar
  25. 25.
    Barailler F, Heniche M, Tanguy PA (2006) CFD analysis of a rotor-stator mixer with viscous fluids. Chem Eng Sci 61(9):2888–2894CrossRefGoogle Scholar
  26. 26.
    Apparatus and method for high-shear mixing. US. Patent Application, US20160271575A1. 22 Sept 2016Google Scholar
  27. 27.
    Rayleigh JWS (1891) Some applications of photography. Nature 44:249–254CrossRefGoogle Scholar
  28. 28.
    Nollet, JA (1749) Recherches sur les causes particulieres des phénoménes électriques, et sur les effets nuisibles ou avantageux qu’on peut en attendre. A Paris: chez les Freres Guerin, ParisGoogle Scholar
  29. 29.
    Eggers J, Villermaux E (2008) Physics of liquid jets. Rep Prog Phys 71(3):036601CrossRefGoogle Scholar
  30. 30.
    Gohil TB, Saha AK, Muralidhar K (2010) Control of flow in forced jets: a comparison of round and square cross sections. J Vis 13:141–149CrossRefGoogle Scholar
  31. 31.
    Brodkey RS, Hershey HC (2003) Transport phenomena: a unified approach. Brodkey Publishing, Columbus, OhioGoogle Scholar
  32. 32.
    Mortensen HH, Calabrese RV, Innings F, Rosendahl L (2011) Characteristics of batch rotor–stator mixer performance elucidated by shaft torque and angle resolved PIV measurements. Can J Chem Eng 89(5):1076–1095CrossRefGoogle Scholar
  33. 33.
    Utomo AD (2009) Flow patterns and energy dissipation rates in batch rotor-stator mixers. PhD thesis, University of BirminghamGoogle Scholar
  34. 34.
    Roesler J, Harders H, Baeker M (2007) Mechanical behaviour of engineering materials. Springer, BerlinGoogle Scholar
  35. 35.
    Smirnov BM (1992) Cluster Ions and van der Waals Molecules. CRC Press, Boca RatonGoogle Scholar
  36. 36.
    Il’inskii YA, Keldysh LV (2013) Electromagnetic response of material media. Springer, BerlinGoogle Scholar
  37. 37.
    Men H, Jiang B, Fan Z (2010) Mechanisms of grain refinement by intensive shearing of AZ91 alloy melt. Acta Mater 58(18):6526–6534CrossRefGoogle Scholar

Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  • Agnieszka Dybalska
    • 1
    Email author
  • Dmitry G. Eskin
    • 1
  • Jayesh B. Patel
    • 1
  1. 1.BCAST, Brunel University LondonUxbridgeUK

Personalised recommendations