Processing resin transfer moulding

Mcllhagger, A., Brown, D., and Hill, B. (2000). The development of a dielectric system for the on-line cure monitoring of the resin transfer moulding process. Composites Part A Appl. Sci. Manuf. 31(12), 1373-1381. 

Low clamping pressures only are needed, and this in turn means that quite large products can be made on inexpensive plant. By varying the raw materials it is possible to produce either rigid or flexible articles, microcellular or otherwise, and (if required) to include fillers or reinforcing sections. Thermosets other than polyurethane can be used—like epoxides and polyesters (with the latter, the process is known also as resin transfer moulding ). 

In resin-transfer moulding (RTM) there is typically a two-part mould, which forms a cavity corresponding to the final product shape. In the process, as shown in Figure 6.11, reinforcement, typically being a woven roving, cloth or mat, is placed (dry) in the female cavity, and then the male half is placed into position. 

Damage tolerance of fibre reinforced thermoplastic composites Processing of polymer matrices using resin transfer moulding Fractal analysis of wear in short-fibre reinforced thermoplastic composites Rheology flow behavior of associative polymers in coating applications Kevlar-thermoplastic composites... 

Kendall KN, Rudd CD, Owen MJ, Middleton V. Characterisation of the resin transfer moulding process. Compos Manuf 1992 3(2) 235—49. 

Potter KD. The early history of the resin transfer moulding process for aerospace applications. Compos Part A Appl Sci Manuf May 1999 30(5) 619—21. 

A further development is resin transfer moulding (RTM), in which long fibre reinforcement fabrics are cut to shape as preforms and placed in the mould cavity, before the resin is injected. This is potentially a slow process and one alternative is for the preforms to be made rapidly by spraying short fibres onto a suitably shaped pattern coated with an adhesive or binder. 

Manufacturing methods for composites vary from manual to fully automated processes, whereby the latter have better quality control than the former. Wet layup, pultrusion, and filament winding are all discussed in some detail, while other techniques such as pull-winding, resin transfer moulding, vacuum bag moulding, and injection moulding are left to specialized composite materials texts. 

Resin Transfer Moulding (RTM)—A closed mould process in which dry reinforcement in the form of mat or cloth is placed into a matched mould. Resin is then injected in to fill the cavity and flows through the fibres to fill the mould space. 

In order to minimise the number of variables within the programme it was decided to restrict the processes to the minimum feasible number commensurate with producing a valid code. Hence three of the primary processes have been specifically denoted as within the scope of the code. They are hand lay up, pultrusion and resin transfer moulding (RTM). These have been identified as a sensible, minimum range of processes which are necessary to produce components for construction applications. 

Source Reprinted with permission from Abraham D, McCarthy R, Design of polymer composite stmclural components for manufacture by resin transfer moulding (RTM), SAMPE Europe Conference and Exhibition. Proc of 2Cf International SAMPE Europe Conference of the Society for the Advancement of Materials, Paris, France, 407-415, 1999. Copyright 1999, The Society for the Advancement of Material and Process Engineering (SAMPE). 

The processing of polyester matrix composites has also been modelled (3). In reference (3) the resin transfer moulding process (RTM) was modelled and the predictions were experimentally verified. Different m epoxy based materials, in this case the polyester resin gelled fi om the skin to the core as shown in Figure 25. 

The vacuum assisted resin transfer moulding (VARTM) process is a variant of vacuum-infusion RTM in which one of the solid tool faces is replaced by a flexible polymeric film (Fig. 23.14). 

Oksman K (2001) High quality flax fibre emnposites manufactiued by the resin transfer moulding process. J Reinf Plast Compos 20 621-627... 

Resin transfer moulding is used to replace the hand lay-up process for better productivity and quahty. In this process, resin is injected into a closed cavity mold that is filled... 

Resin Transfer Moulding- ROMP Processing, Bulk Polymerisation... 

Vacuum infusion process (VIP), generally referred to as vacuum-assisted resin transfer moulding (VARTM), in which the resin is introduced into the mould and the preform at less than atmospheric pressure (i.e. a vacuum). 

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