Mohammad Saeed Hosseinkhani - Department of Mechanical Engineer, Islamic Azad University, Arak Branch, Arak, Iran,
Mohammad Mahdi Attar - Department of Mechanical Engineer, Islamic Azad University, Hamedan Branch, Hamedan, Iran,

Even though composite materials offer numerous mechanical advantages, they can be associated with damage and failure, just like any other material. The present paper investigates time-dependent effects of fiber volume fraction on stress concentration in polymeric matrix composite materials containing cracks. Most of polymeric materials exhibit viscoelastic behaviors; as such, it is significantly important to take into account effect of time factor when investigating behaviors of polymeric composite materials. In order to consider the effect of fiber volume fraction, a representative volume element of rectangular cubic form was used to represent a composite material. Including two phases, namely matrix and fiber, the model was developed as a centrally symmetrical, two-dimensional finite element model in ANSYS software. Furthermore, the middle fiber of this model contained a linear crack. considering the polymeric matrix as a viscoelastic material, effect of time on stresses around the tip of the crack was calculated for different values of fiber volume fraction. Finally, in viscoelastic matrix composite materials, effect of fiber volume fraction decreased by reducing matrix modulus throughout time.

Viscoelastic, Composite, Crack, Fiber Volume Fraction