Advertisement

Micro-machining with abrasive slurry-jets: effects of dissolved polymer concentration and nozzle design

  • E. van Wijk
  • D. F. James
  • M. Papini
  • J. K. Spelt
ORIGINAL ARTICLE
  • 2 Downloads

Abstract

The resolution of features machined with abrasive slurry jets is dependent on the diameter of the erosion footprint on the workpiece and on the stability of the jet. Previous work has shown that the footprint size decreases, but the jet oscillation increases, with increasing polymer concentration. The present study investigated the effect of nozzle design on jet stability in abrasive slurry-jet micro-machining of glass using slurries with dissolved polymers. A variety of transparent acrylic nozzles were made with different geometries and a 180-μm sapphire orifice to study the oscillation of jets of water mixed with high molecular-weight polyethylene oxide. Fluorescent streak photography of the flows within the nozzles confirmed the presence of unstable vortices that can lead to jet oscillation. However, the dependence of these vortices on nozzle geometry and PEO concentration was unclear. Jet oscillation was then measured photographically and found to increase nonlinearly with polymer concentration for all nozzle geometries. These results were used to design and manufacture a new steel nozzle with a 30° tapered entrance region which reduced jet oscillation. Micro-channels were then machined in glass plates using a range of polymer slurries containing aluminium oxide particles. The polymer concentration that produced the best combination of a relatively small footprint while simultaneously minimizing the jet oscillation amplitude resulted in channels that were 11% narrower than reference channels machined with a pure water slurry and a standard nozzle.

Keywords

Viscoelasticity Contraction flows Jet stability Footprint Abrasive slurry-jet machining 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Notes

Acknowledgements

The work was supported by the Natural Sciences and Engineering Research Council of Canada.

References

  1. 1.
    Molitoris M, Piteľ J, Hošovský A, Tóthová M, Židek K (2016) A review of research on water jet with slurry injection. Procedia Eng 149:333–339.  https://doi.org/10.1016/j.proeng.2016.06.675 CrossRefGoogle Scholar
  2. 2.
    Liu H (2010) Waterjet technology for machining fine features pertaining to micromachining. J Manuf Process 12:8–18.  https://doi.org/10.1016/j.jmapro.2010.01.002 CrossRefGoogle Scholar
  3. 3.
    Nguyen T, Shanmugam D, Wang J (2008) Effect of liquid properties on the stability of an abrasive waterjet. Int J Mach Tools Manuf 48:1138–1147CrossRefGoogle Scholar
  4. 4.
    Kowsari K, James DF, Papini M, Spelt JK (2014) The effects of dilute polymer solution elasticity and viscosity on abrasive slurry jet micro-machining of glass. Wear 309:112–119.  https://doi.org/10.1016/j.wear.2013.11.011 CrossRefGoogle Scholar
  5. 5.
    Barnes HA, Hutton JF, Walters K (1993) An introduction to rheology. Vol. 3, 1st edn. Elsevier B.V, AmsterdamzbMATHGoogle Scholar
  6. 6.
    Holtmeyer MD, Chatterji J (1980) Study of oil soluble polymers as drag reducers. Polym Eng Sci 20:473–477CrossRefGoogle Scholar
  7. 7.
    Hoyt JW, Taylor JJ, Runge CD (1974) The structure of jets of water and polymer solution in air. J Fluid Mech 63:635–640.  https://doi.org/10.1017/S0022112074002102 CrossRefGoogle Scholar
  8. 8.
    Boger DV, Williams HL (1972) Predicting melt flow instability from a criterion based on the behavior of polymer solutions. Polym Eng Sci 12:309–314CrossRefGoogle Scholar
  9. 9.
    Nguyen H, Boger DV (1979) The kinematics and stability of die entry flows. J Nonnewton Fluid Mech 5:353–368.  https://doi.org/10.1016/0377-0257(79)85023-5. CrossRefGoogle Scholar
  10. 10.
    Boger DV, Crochet MJ, Keiller RA (1992) On viscoelastic flows through abrupt contractions. J Nonnewton Fluid Mech 44:267–279.  https://doi.org/10.1016/0377-0257(92)80053-Z CrossRefGoogle Scholar
  11. 11.
    Evans RE, Walters K (1986) Flow characteristics associated with abrupt changes in geometry in the case of highly elastic liquids. J Nonnewton Fluid Mech 20:11–29.  https://doi.org/10.1016/0377-0257(86)80013-1 CrossRefGoogle Scholar
  12. 12.
    Boger DV, Walters K (1993) Rheological phenomena in focus. 1st ed. Elsevier Science Publishers B.V, Amsterdam, pp 35–72zbMATHGoogle Scholar
  13. 13.
    Chiba K, Nakamura K (1997) Instabilities in a circular entry flow of dilute polymer solutions. J Nonnewton Fluid Mech 73:67–80.  https://doi.org/10.1016/S0377-0257(97)00036-0 CrossRefGoogle Scholar
  14. 14.
    Nouraei H, Kowsari K, Spelt JK, Papini M (2014) Surface evolution models for abrasive slurry jet micro-machining of channels and holes in glass. Wear 309:65–73.  https://doi.org/10.1016/j.wear.2013.11.003 CrossRefGoogle Scholar
  15. 15.
    Kowsari K, Nouraei H, James DF, Spelt JK, Papini M (2014) Abrasive slurry jet micro-machining of holes in brittle and ductile materials. J Mater Process Technol 214:1909–1920.  https://doi.org/10.1016/j.jmatprotec.2014.04.008 CrossRefGoogle Scholar
  16. 16.
    Anna SL, McKinley GH (2001) Elasto-capillary thinning and breakup of model elastic liquids. J Rheol (N Y N Y) 45:115–138.  https://doi.org/10.1122/1.1332389. CrossRefGoogle Scholar
  17. 17.
    McKinley GH (2005) Visco-elasto-capillary thinning and break-up of complex fluids. http://hdl.handle.net/1721.1/18085
  18. 18.
    ASTM C702 / C702M-18, Standard practice for reducing samples of aggregate to testing size.  https://doi.org/10.1520/C0702_C0702M-18
  19. 19.
    Dutta NN, Pangarkar VG (1995) Critical impeller speed for solid suspension in multi-impeller three phase agitated contactors. Can J Chem Eng 73:273–283CrossRefGoogle Scholar
  20. 20.
    Booth C (1963) The mechanical degradation of polymers. Polymer (Guildf) 4:471–478.  https://doi.org/10.1016/0032-3861(63)90060-0. CrossRefGoogle Scholar

Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Mechanical and Industrial EngineeringUniversity of TorontoTorontoCanada
  2. 2.Department of Mechanical and Industrial EngineeringRyerson UniversityTorontoCanada

Personalised recommendations