Journal of Materials Science

, Volume 11, Issue 6, pp 1077–1082 | Cite as

On the spheroidization of rod-shaped particles of finite length

  • F. A. Nichols
Papers

Abstract

The governing equation for the capillarity-induced shape changes of a surface of revolution by surface diffusion,
$$\frac{{\partial n}}{{\partial t}} = \frac{B}{y}\frac{\partial }{{\partial s}}\left( {y\frac{{\partial K}}{{\partial s}}} \right)$$
where∂n/∂t is the normal velocity of the surface,y is measured normal to the axis of revolution,s is arc length,K is the total surface curvature andB is a kinetic parameter which is constant for a given temperature and material, is presented. A numerical solution to this equation is used to analyse finite cylinders with hemispherical ends. A critical length-to-diameter ratio (L/D) of 7.2 is predicted, below which only one spheroidal particle results and above which two or more are formed, and is shown to have experimental support in several systems.

Keywords

Polymer Kinetic Parameter Surface Curvature Shape Change Surface Diffusion 

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Copyright information

© Chapman and Hall Ltd. 1976

Authors and Affiliations

  • F. A. Nichols
    • 1
  1. 1.Materials and Structural Mechanics, Bettis Atomic Power LaboratoryWestinghouse Electric CorporationWest MifflinUSA

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