Skip to main content
Log in

Comparing two measures of flake alignment

  • Published:
Wood Science and Technology Aims and scope Submit manuscript


Alignment of particles in structural composites is desirable to increase the strength and stiffness of the panel in one direction. The magnitude of resulting orthotropic panel properties are influenced by the degree of alignment. Quantification of the degree of alignment in the literature has primarily been attained by a parameter known as percent alignment. Measures of flake alignment in probability distribution form have received some, though more limited attention. However, use of statistical distributions to describes particle orientation, such as that provided by the von Mises distribution are needed for simulations of composite panel properties. It is shown that percent flake alignment is a linear transformation of the first moment (arithmetic mean) of the absolute value of angles in the range ±90 degrees. Assuming the von Mises distributional form accurately measures flake alignment, this implies that percent flake alignment is a measure of both the variability in flake direction and the mean flake angle. The numerical relationship of percent alignment with mean angle and variability is presented with a look-up table provided for converting between the two systems of measure. The relation will permit verification of models which employ the von Mises distribution to describe flake alignment using information in the literature based on percent flake alignment. A computer program is available from the author which will calculate percent alignment and distribution parameters for an experimentally obtained samples of angles.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others


  • Geimer, R. L. 1976: Flake alignment in particleboard as affected by machine variables and particle geometry. Res. Paper 275. Madison, WI: U.S. Dept. of Agric., Forest Prod. Lab.

    Google Scholar 

  • Geimer, R. L. 1986: Mechanical property ratios: A measure of flake alignment. Res. Paper 468. Madison, WI: U.S. Dept. of Agric., Forest Prod. Lab.

    Google Scholar 

  • Harris, R. A.; Johnson, J. J. 1982: Characterization of flake orientation by the von Mises probability distribution function. Wood Fiber. 14:254–266

    Google Scholar 

  • Larson, H. J.; Shubert, B. O. 1979: Probabilistic models in engineering sciences. Vol. I: random variables and stochastic processes. New York: J. Wiley Sons

    Google Scholar 

  • Lau, P-W, C. 1981: Numerical approach to predict the modulus of elasticity of oriented wafer-board. Wood Sci 14:73–85

    Google Scholar 

  • Lyon, D. E.; Thaggard, C. E. 1988: The use of computer simulation modeling to predict properties of oriented flakeboard. In: Structural wood composites: New technologies for expanding markets. M. P. Hamel (Ed.) Forest Prod. Res. Soc. Madison, WI.

    Google Scholar 

  • Marida, K. V. 1972: Statistics of directional data. London; Acad. Press

    Google Scholar 

  • Shaler, S. M. 1986: Usefulness of selected polymer composite theories to predict the elastic moduli of oriented flakeboard. Ph.D. Dissertation. Pennsylvania State University, University Park, Pa.

    Google Scholar 

  • Shaler, S. M.; Blankenhorn, P. R. 1990: Composite model predication of elastic moduli for flakeboard. Wood Fiber Sci. 22:246–261

    Article  CAS  Google Scholar 

  • Zar, J. H. 1984. Biostatistical analysis. 2nd Ed. New York: Prentice-Hall Inc.

    Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

About this article

Cite this article

Shaler, S.M. Comparing two measures of flake alignment. Wood Sci.Technol. 26, 53–61 (1991).

Download citation

  • Received:

  • Issue Date:

  • DOI: