The process and microstructure modeling of long-fiber thermoplastic composites

Abstract

Interest in thermoplastic matrix composites has increased in recent years due to several advantages of these materials, including high volume process ability, recyclability, superior damage tolerance and fracture toughness, and ability to produce complex shapes. Among thermoplastic composites, long-fi ber thermoplastics (LFTs) are fi nding increased use in the automotive and transportation sector. Predictive process and material characterization tools are much needed in industry to minimize expensive tooling/process trials and to improve the design avenues for parts produced using LFTs. The current work focuses on fi nite element simulation of LFT materials for two scenarios: fi rst, process modeling of LFTs to evaluate the fl ow of fi berfi lled viscous charge during compression molding and the resulting fi ber orientation prediction and, second, modulus prediction of LFT materials accounting for fi ber orientation and distribution. Together these tools provide insight into the process and performance characteristics of LFT materials.

A review of Long fibre thermoplastic (LFT) composites

“…The flow of the LFT melt during compression moulding also leads to preferable fibre orientations, which is, however, not as high as that experienced in injection moulding. A preferable fibre orientation can still induce a difference in mechanical properties between the flow and transverse directions [27,[165][166][167]. For a 40 wt-% glass/PP LFT, the tensile strength in the longitudinal direction was 114 MPa, but only 68 MPa in the transverse direction [166].…”

“…A preferable fibre orientation can still induce a difference in mechanical properties between the flow and transverse directions [27,[165][166][167]. For a 40 wt-% glass/PP LFT, the tensile strength in the longitudinal direction was 114 MPa, but only 68 MPa in the transverse direction [166]. Microstructural analysis performed on observing the fibre orientation in the glass/PP LFT has verified the preferable fibre orientation in the flow direction [166].…”

An investigation to enhance the mechanical property of high‐performance thermoplastic composite through different plasma treatment

“…In recent years, carbon fiber‐reinforced polymer composites have been widely used in a variety of applications, ranging from highly critical sectors like aerospace, [ 1,2 ] oil and gas, [ 3 ] automobile [ 4,5 ] to precision goods such as sporting equipment. The types of carbon fiber‐reinforced composites differ in their resin type, that is, thermosets or thermoplastics, as well as in the reinforcement form, for example, discontinuous, unidirectional, or woven fabric.…”

Method to measure orientation of discontinuous fiber embedded in the polymer matrix from computerized tomography scan data

“…2,3 The mechanical properties of chopped fiber thermoplastic material greatly depend on the following: (1) mechanical properties of the fibers; (2) mechanical properties of the thermoplastic resin material; (3) condition of the chopped fibers in the composite material; and (4) fiber-resin interface condition. [4][5][6] Assuming that the fibers are well dispersed, the main criteria for fiber condition are fiber length, fiber orientation, and volume fraction of the fiber in the polymer.…”