Young's Modulus of Coated Inclusion Composites by the Generalized Mechanics-of-Materials (GMM) Approach

Abstract

A micromechanical model of the Young's modulus for three special cases of composites - continuous unidirectional fiber composites, particulate composites and periodically bilaminate composites - has been developed within the framework of the mechanic-of-materials approach. Parallel-series (PS) and series-parallel (SP) schemes were adopted based upon opposing combination sequence of the parallel model (direct rule-of-mixture) and the series model (inverse rule-of-mixture). By expressing the inclusion's geometrical characteristics in terms of reinforcement volume fraction and interphase volume, a set of reinforcement parameters for the inclusion and its interphase are extracted. Based on reinforcement parameters for the special cases, those of more general cases, which are intermediates of the special cases, are obtained by curve-fitting approximation. Young's modulus of simple cases such as coated fiber composites in longitudinal direction and coated lamina composites are shown to be approximate to the parallel and series models respectively. Cases such as coated fiber composites in transverse direction and coated particulate composites are compared with other results and observed to be highly and moderately conservative by the PS and SP techniques respectively.

On the static and dynamic properties of fiber-reinforced polymer composites

“…For the two phases of the fiber and interphase in our three-phase model, the bridging matrix ½A fi ij between the fiber and interphase is first deduced. The compliance matrices of constituents ½S f ij , ½S i ij , and ½S m ij are the same form as the above in equation (12). As the compliance matrix was obtained based on the bridging relationships of constituents, the bridging matrix ½A fi ij should also be the diagonal form in light of equation ( 12):…”

“…7,8 The effects of the interphase on the mechanical properties of fiber-reinforced composites have been investigated in literature. 9,10 Especially, a generalized mechanics-of-materials approach for three-phase composites including the interphase was also proposed by Lim 11,12 to study the performance of FRP composites. Therefore, the interphase is actually important for the prediction of the material's overall performance in FRP composites.…”

The experiment and simulation of enhanced mechanical performance for polyethylene terephthalate/high‐density polyethylene composites via domain size control

“…The Young's modulus and flexural modulus of the composites displayed a similar trend to that of tensile strength, but with a narrow range of variation. This is because that according to the mixing law, Young's modulus of composites is primarily determined by the proportion of each component in the blend, thus under the same PET content and elastic stage, Young's modulus showed small deviation 67 . The enhancement in tensile and flexural strength can be attributed to the optimized domain size and dispersion of PET in the composite matrix, achieving through the S3M process.…”

“…This is because that according to the mixing law, Young's modulus of composites is primarily determined by the proportion of each component in the blend, thus under the same PET content and elastic stage, Young's modulus showed small deviation. 67 The enhancement in tensile and flexural strength can be attributed to the optimized domain size and dispersion of PET in the composite matrix, achieving through the S3M process. At low milling cycle, PET had large domain size, uneven dispersion and was thermodynamically incompatible with HDPE, resulting in poor interfacial adhesion and decreased tensile strength.…”

Reinforcement Parameters of Aligned Ellipsoidal Inclusions by the Generalized Mechanics-of-materials (GMM) Approach

“…The present approach can be extended to obtain elastic stiffness of coated ellipsoidal inclusion, since similar approach has been successfully attempted for coated particulate composites and coated fiber composites [43]. It remains to be seen whether the elastic model can be made analogous to thermal conductivity model, which was previously attempted using the GMM approach for particulate and fiber reinforced composites [44].…”