On the effect of geometrical fiber arrangement on damage initiation in CFRPs under transverse tension and compression Articles uri icon

publication date

  • October 2021

start page

  • 1

end page

  • 10

issue

  • 114360

volume

  • 274

International Standard Serial Number (ISSN)

  • 0263-8223

Electronic International Standard Serial Number (EISSN)

  • 1879-1085

abstract

  • The mechanical performance of composite materials is strongly dependent on its microstructure. Efficient
    design of composites requires proper estimation of the effect of the microstructure on residual stresses that arising
    from cooling due to manufacturing temperature. The study of the stresses and damage in fibres interface
    and its relationship with geometrical distribution of the fibres can contribute to a better comprehension of
    the mechanical response of the composite.
    We use 2D numerical models to represent a composite material reinforced with longitudinal fibres. The
    mechanical behaviour is analysed taking into account the cooling effect and tension/compression transverse
    loading. We have generated a range of virtual microstructures, characterized by the microstructure randomness,
    to study the influence of the fiber randomness on the damage initiation. Damage initiation at fibres interfaces
    has been estimated from the stresses induced at the interface, both in the whole structure and for
    individual fibers.
    As expected, a strong effect of the randomness of the fiber arrangement on the damage initiation has been
    found. For all microstructures and loading modes, higher values of microstructure randomness results in earlier
    damage development. Normal and shear stresses at individual fibre interfaces have been analysed under tension
    and compression loading. In tension, normal stress at the fiber interface fully dominates the interfacial
    damage initiation. In compression, damage is almost completely dominated by the interfacial tangential stress.
    In compression, localized plasticity develops simultaneously with damage initiation whereas in tension, damage
    initiation occurs at a stress three times lower than the required for the onset of plasticity. The maximum
    shear and normal stresses around individual fibers are strongly affected by the local neighborhood.

subjects

  • Mechanical Engineering

keywords

  • interface damage; random fiber distributions; cooling effect; periodic boundary conditions