G. Li et Pp. Castaneda, THE EFFECT OF PARTICLE-SHAPE AND STIFFNESS ON THE CONSTITUTIVE BEHAVIOR OF METAL-MATRIX COMPOSITES, International journal of solids and structures, 30(23), 1993, pp. 3189-3209
Citations number
47
Categorie Soggetti
Construcion & Building Technology","Engineering, Civil
This paper deals with the effective constitutive behavior of ductile m
etals reinforced by aligned spheroidal inclusions with linear-elastic
properties. For simplicity, both the matrix and the inclusions are ass
umed to be incompressible and isotropic, so that the overall constitut
ive behavior of the metal-matrix composites is incompressible and tran
sversely isotropic. Based on a recently proposed variational method fo
r estimating the effective behavior of nonlinear composites, results a
re obtained for the initial yield surfaces and overall stress-strain r
elations in terms of the three essentially distinct loading modes for
this class of composites: Axisymmetric tension (relative to the symmet
ry axis of the inclusions), longitudinal shear (along the symmetry axi
s) and transverse shear (perpendicular to the symmetry axis). It is fo
und that particle shape has a significant effect on the effective resp
onse of the composites, and that this effect is markedly different for
the three loading modes. For the axisymmetric mode, oblate and prolat
e shapes have the largest strengthening effects; for the transverse mo
de, oblate shapes are most effective; and for the longitudinal mode, n
early spherical shapes are best. Particle stiffness also has a strong
effect on the initial yielding behavior of the composites, which is ma
gnified for the more severe aspect ratios. On the other hand, the stif
fness of the particles does not seem to significantly affect the stres
s-strain behavior of the composites for strains greater than about fiv
e times the yield value.