Unidirectional Fiber Reinforced Plastic Composites Research Articles

Coupling inverse fin method with infrared thermography to determine the effective thermal conductivity of extruded thermoplastic foams

An inverse method for determining the in-plane effective thermal conductivity of porous thermoplastics was implemented by coupling infrared thermography experiments and numerical simulation of heat transfer in straight fins having temperature-dependent convective heat transfer coefficient. The microstructure heterogeneity of extruded polyethylene foam, in which pores are filled with air with different levels of open and closed porosity, was taken into account. The obtained effective thermal conductivity values were compared with previous results obtained using a numerical solution based on periodic homogenization techniques (NSHT) and the transient plane source technique (TPS) to verify the accuracy of the proposed method. The results show that the suggested method is in good agreement with both NSHT and TPS. Moreover, it is also appropriate for structural materials such as unidirectional fiber-reinforced plastic composites, where heat transfer is very different according to the fiber direction (parallel or transverse to the fibers).

On the Sliding Friction Characteristics of Unidirectional Continuous FRP Composites

By applying a closed-form analytical solution Hwu and Fan (1998) for an anisotropic half-plane, the contact characteristics of unidirectional continuous fiber-reinforced plastic (FRP) composites are investigated. The particular condition of a rigid parabolic cylinder in normal sliding contact with the composite is evaluated. The influence of FRP composite matrix material, friction coefficient, fiber material, fiber orientation, and fiber volume fraction on the surface contact pressure are determined and evaluated by comparison to published experimental data and results from the finite element method. From the analytical results, several important trends for the contact characteristics of fiber-reinforced plastics are ascertained and discussed with respect to the wear and design-ability of FRP materials.