Manufacturing of polygon fiber reinforced plastic profiles by rotational molding and intrinsic hybridization

Abstract

The manufacturing of lightweight shafts, pipes and profiles often uses hollow structures made from fiber reinforced plastics (FRP) due to their better density related properties. For applications with locally high tribological stresses, the use of FRP is not yielding proper results. In terms of lightweight construction, a hybrid design with a hollow FRP basic structure and local metallic elements in areas of high tribological stress is ideal for these applications. A promising approach for the production of these parts is rotational molding. Rotational molding for FRPmetal profiles is understood as a manufacturing process where machined, metallic elements and dry continuous fiber structures will be assembled and laid in a closed mold. Afterwards, the liquid matrix will be casted and the mold is then rotated at high speed until the fiber structure is fully impregnated and the matrix is cured. As there are short flow paths, this process is offering the potential to realize short cycle times of only a few minutes. Within this paper, the manufacturing of polygon profiles via rotational molding is described. These profiles can be produced by using centrifugal cores which were developed at the wbk Institute of Production Science. These cores are made of an elastomer composite material and they expand during the rotational molding process. The modeling of these cores and their impact on the impregnation pressure is shown here as well as their contribution in achieving higher fiber volume fractions.

Rotomolding and polyethylene composites with rotomolded lignocellulosic materials: A review

“…31 Polylactic acid, 32–36 poly(epsilon-caprolactone), 37 polyether ether ketone, 38 polyvinylidene fluoride, 25,26 and polymethylmethacrylate 25 are also rotomolded. The use of rotomolding for thermosetting materials was also observed, such as epoxy resins, 39 polyurethane, 40 phenolic resins, 41 and unsaturated polyester. 1,42 Inorganic fillers used in rotomolded material include wollastonite 43 and halloysite clay, 44 calcium carbonate, 45 graphite, 30,46,47 silica, 48–51 carbon nanotubes, 52 glass fibers, 52–55 and carbon.…”

Production and Tensile Testing of Rotationally Molded Hybrid Composite Tie Rods

“…An innovative process for the intrinsic production of hollow structures made of FRP and metal is the rotational molding process [2,4]. A dry and hollow fiber preform is inserted into a mold, together with the metallic load introduction elements.…”

“…First studies of the rotational molding process have already been conducted and a rough feasibility of the process could be demonstrated as both fiber volume content and geometric fidelity are satisfactory [4,14]. Therefore, the objective of this paper is to evaluate the mechanical strength and the energy absorption during failure of the intrinsically manufactured FRP-metal joint.…”

Experimental and Numerical Analysis of Mold Filling in Rotational Molding

“…In the early days of this process, cutted glass fibers with matrix were often used for liquid containers and silos [4,5]. Meanwhile, structural components are also manufactured for which a dry perform with continuous fiber reinforcement is used [6][7][8][9]. This preform made of semi-finished products is placed in a mold and impregnated with a matrix under rotation (see Figure 1).…”

“…This preform made of semi-finished products is placed in a mold and impregnated with a matrix under rotation (see Figure 1). The matrix used can be either thermoplastic [6] or thermoset [7,9]. The impregnation pressure is generated by the resulting centrifugal force due to the rotation.…”