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The Theoretical Optimum Rolling Speed in Powder Compaction

  • P. E. Evans

Abstract

When a metal powder is compacted by rolling, expulsion of the interparticle gas causes a disturbance in the powder bed. This has a fluidization effect and increases with increasing rolling speed; hence, maximum rolling speed is limited. The criterion for optimum rolling speed is taken as that speed below which the velocity of gas expulsion (measured at the coherent-noncoherent interface of the powder in the rolling gap) is just insufficient to promote fluidization. An analysis is presented which shows that the velocity of gas expulsion is proportional to rolling speed, roll radius, and a function of the gripping angle. Methods of increasing the optimum rolling speed are suggested.

Keywords

Mass Velocity Rolling Speed Nickel Powder Powder Compaction Roll Radius 
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References

  1. 1.
    Evans, P. E., “The Mechanism of the Compaction of Metal Powders by Rolling,” Planseeber. Pulvermet. 7(3): 102–116 (1959).Google Scholar
  2. 2.
    Worn, D. K., and R. P. Perks, “Production of Pure Nickel Strip by the Direct Rolling Process,” Powder Met. 3: 45 (1959).Google Scholar
  3. 3.
    Wilhelm, R. H, and S. Valentine, Ind. Eng. Chem. 43: 1199 (1951).CrossRefGoogle Scholar
  4. 4.
    Leva, M., Fluidization, McGraw-Hill (New York), 1959.Google Scholar
  5. 5.
    Leva, M., loc. cit., Chapter 3.Google Scholar
  6. 6.
    Tafel, W., and E. Schneider, Stahl Eisen 44: 305 (1924).Google Scholar
  7. 7.
    Evans, P. E., and G. C. Smith, “The Compaction of Metal Powders by Rolling: II—An Examination of the Compaction Process,” Powder Met. 3: 26 (1959).Google Scholar
  8. 8.
    Deibel, C., D. R. Thornburg, and F. Emley, “Continuous Compaction by Cyclic Pressing,” Powder Met. 5: 32(1960).Google Scholar

Copyright information

© Metal Powder Industries Federation and The Metallurgical Society of AIME 1966

Authors and Affiliations

  • P. E. Evans
    • 1
  1. 1.Manchester UniversityManchesterEngland

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