Effect of elastic or shape memory alloy particles on the properties of fiber-reinforced composites

Abstract

The paper presents a comprehensive formulation for the analysis of the stiffness and strength of fiberreinforced composites with the matrix enhanced by adding elastic or shape memory alloy (SMA) spheroidal particles. The micromechanical model used to evaluate the stiffness tensor of the matrix with embedded particles is based on the Benveniste version of the Mori-Tanaka theory. In the case of a superelastic shape memory alloy particulate matrix, the stiffness of the particles depends on the martensitic fraction that is in turn affected by the state of stress within the particle. In this case an exact solution for the stiffness tensor of the composite material with elastic fibers and matrix and embedded SMA particles is developed combining the recent macromechanical solution for multi-phase composites with the inverse method of the analysis of SMA. In the particular case, this solution results in explicit formulae for the homogeneous material constants of a SMA particulate material subjected to axial loading. Upon the completion of the stiffness analysis the strengths of a fiber-reinforced material with the matrix containing elastic or SMA particles can be analyzed using the Eshelby solution for the stresses. As follows from numerical examples, elastic spherical particles added to the matrix of a fiber-reinforced composite significantly improve the transverse strength and stiffness of the material, even if the volume fraction of such particles is relatively small. The effect of elastic particles on the longitudinal strength and stiffness is less pronounced. It is also illustrated that the stress-induced transformation of superelastic SMA particles results in significant changes of the properties of SMA particulate composites.

Properties and response of composite material with spheroidal superelastic shape memory alloy inclusions subject to three-dimensional stress state

“…It is possible to express the increment of the effective stress in terms of the increment of the applied composite stress tensor using (3), so that dσ eff = d (ξ, σ 0 ), (5) where (ξ, σ 0 ) is a nonlinear function of applied stresses and the martensite fraction. In particular, in the case of a uniaxial load, (11) 0…”

“…Numerous phenomenological theories rely on assumptions regarding the relationship between the rates of change in the martensite volume fraction and the transformation strain tensor. The 'inverse' approach to the analysis that estimates applied stresses as functions of the martensite fraction was proposed for fibrous SMA composites [4] and for particulate SMA composites subject to uniaxial loading [5]. This approach is applicable if the transformation kinetics law of the SMA material is prescribed as is the case in the phenomenological theories of Tanaka [6,7], Liang-Rogers [8], Boyd-Lagoudas [9,10] and Brinson [11].…”

“…These curves illustrate that the complete transformation can be accomplished only at high applied stresses exceeding 500 MPa that may cause plastic flow in the matrix. Even in the case of epoxy matrix the stresses producing the complete transformation are quite high [5]. Accordingly, it may be difficult to design composites with epoxy matrices utilizing the phase transformation in SMA particles (or fibres).…”

A review on shape memory alloy reinforced polymer composite materials and structures

“…Shape control of polymer composites has not been investigated for controlling the shape of structures. SMA particulates were embedded into the grooves with a silicon matrix [160].…”

Review and perspectives: shape memory alloy composite systems

“…13b). Birman [57,58] developed a similar numerical scheme to investigate the effect of randomly distributed SMA spheroidal particles on the effective thermomechanical properties [57] and stress-strain loop reflecting hysteresis of fiber-reinforced polymer composites and on the stress states of SMA particle reinforced MMCs [58]. The Mori-Tanaka homogenization technique was used at both levels to develop relations between the properties of the composite material and the applied stresses.…”