A micromechanical creep model for stress analysis of non-reinforced regions of short fiber composites using imaginary fiber technique

• Stress analysis of non-reinforced regions in creeping short fiber composites.
• Creep analysis based on well-behaved displacement rates without using shear lag model.
• Obtaining creep behavior using basic equations and imaginary fiber technique.
• Presenting a simple method for creep analysis unlike difficult experimental method.
• Good agreements are found between the analytical and numerical results.

Stress behavior in short fiber composites under axial tensile stress is predicted based on well-behaved displacement rates in the steady state creep using imaginary fiber technique. This analysis is performed without using shear-lag model and other complex theories in non-reinforced regions of the short fiber composites. Direct analytical method (DAM) is presented to obtain the composite creep strain rate and stress behavior. Because of many applications of silicon carbide fiber SiC/Al6061 composites, stress analysis of this composite is done. Good agreements are found between the obtained present analytical and finite element method (FEM) results. Some important applications of the present comprehensive method are in the fields of the safe composite design and control of creeping composites in order to prevent the creep rupture. Also, present method is simple and accurate, unlike costly, difficult and time-consuming experimental methods.