Generalized Initial Yield Surfaces for Unidirectional Composites

[+] Author and Article Information
G. J. Dvorak, M. S. M. Rao, J. Q. Tarn

Department of Civil Engineering, Duke University, Durham, N. C.

J. Appl. Mech 41(1), 249-253 (Mar 01, 1974) (5 pages) doi:10.1115/1.3423235 History: Received February 01, 1973; Revised April 01, 1973; Online July 12, 2010


A numerical method is described for determination of generalized initial yield surfaces of unidirectional metal matrix composites under arbitrary external loads and uniform temperature changes. The method leads to the representation of the surface in a three-dimensional system of generalized stress coordinates which, respectively, coincide with the direction of the normal composite stress in the fiber direction, and with the two principal directions of the composite stresses acting in the transverse plane. The initial yield surface of the composite is an irregular ellipsoid with its longest axis inclined toward the hydrostatic stress axis. A thermomechanical analogy is used to show that as a result of a uniform temperature change, the yield surface experiences a rigid-body translation in the direction of the hydrostatic axis in the stress space. The initial yield behavior of a B-Al composite is described in detail. It is shown that microplastic yielding can take place in the composite under relatively small magnitudes of external loads, and hydrostatic stress, or as a result of moderate temperature changes.

Copyright © 1974 by ASME
Your Session has timed out. Please sign back in to continue.






Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In