Vacuum-Assisted Resin Transfer Molding VARTM

3 Vacuum-Assisted Resin Transfer Molding (VARTM) 

Pultrusion is a modern technique used for producing continuous fiber-reinforced profile in which the orientation of the fiber is kept constant during cure. Although this process is utilized for both thermoplastic and thermoset resins, it is mainly suitable for thermosetting resins like polyester, epoxy and phenolic resin systems. Jute, available in continuous forms such as mat, roving, tapes, yarn, etc., is impregnated with 

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Hsiao K-T, Heider D. Vacuum assisted resin transfer molding (VARTM) in polymer matrix composites. In Advani S, Hsiao K-T, editors. Manufacturing techniques for polymer matrix composites (PMCs). Cambridge (UK) Woodhead Publishing Limited 2012. 

Vacuum-assisted resin transfer molding (VARTM) is a process to form and shape FRP composites. Fibers are layered on a solid mold base and covered by a vacuum bag. By generating a vacuum, the vacuum bag is compacted owing to the action of atmospheric pressure, and, therefore, air bubbles are ehminated. Porous fabrics absorb excess resin and the entire material is cured to obtain better mechanical properties. This processing technology is suitable to a certain level of automation and ensures a good geometrical control and a smooth surface. 

Vacuum assisted resin transfer molding (VARTM) [68]... 

Occasionally, fibers or tows are inserted or laid into a shape as a preform, and the whole preform is subjected to the injection of the resin system under pressure, such as resin transfer molding (RTM) vacuum-assisted resin transfer molding (VaRTM) or even partial injection of the resin or part of the resin system, with the same qualified resin transfer molding (SqRTM) process. In every case, there is the real possibility of fibers moving under the influence of the injected resin, producing considerable doubt as to the final formal structure, position, or integrity of the fibers after molding. 

Johnson, R. J. and Pitchumani, R. (2008), Active control of reactive resin flow in a vacuum assisted resin transfer molding (VARTM) process . Journal of Composite Materials, 48(12), 1205-1229. 

Heated tools for example for RTM, vacuum-assisted resin transfer molding (VARTM) or same qualified resin transfer molding (SQRTM) (same qualified RTM). 

Walsh SM, Freese CE. Numerical model of relaxation during vacuum-assisted resin transfer molding (VARTM). Polymer Composites, 2005 26(5) 628-635. DOI http //dx.doi.org/10.1002/pc.20135. 

Nasim U, Uday V, Muhammad S, Serrano-Perez JC. Cost-effective bridge girder strengthening using vacuum-assisted resin transfer molding (VARTM). Advanced Composite Materials, 2004 13(3 ) 255-281. DOI 10.1163/1568551042580163. 

The textile preform is placed in a tool to shape the part. LCM processes can be structured according to the tool used. Infusion processes like Resin Transfer Molding (RTM), Compression Resin Transfer Molding (CRTM), and Structural Reaction Injection Molding (SHIM) utilize a double sided mold. In contrast, Vacuum Assisted Resin Transfer Molding (VARTM), Rotational Molding (RM), and the Cured-In-Place Pipe process (CIPP) need only one rigid tool wall,... 

Zhang Y, Lopatnikov S and Heider D (2005) Modeling of distribution media and vacuum bag properties on permeability variations during vacuum assisted resin transfer molding (VARTM), Proc ASME Int Mech Congr and Exposition, Nov 5-11, Orlando, Florida, pp. 1-8. 

Lin, L., Lee, J., Hong, C., Yoo, G., Advani, S., 2006. Preparation and characterization of layered siUcate/glass fiber/epoxy hybrid nanocomposites via vacuum assisted resin transfer molding (VARTM). Composite Science and Technology 66, 2116—2125. 

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