The effect of vacuum assistance, mould temperature and ram velocity on the void transport and flow behaviour for sheet moulding compound (SMC) have been investigated with a design of experiment approach of the compression moulding phase. The relative amount of voids has been quantified with a high voltage insulation test and the flow behaviour has been quantified with image analysis of samples moulded with coloured SMC. In conclusion, the setting of high vacuum, low ram velocity and low mould temperature creates a homogeneous flow and minimises the amount of voids.
KiaH. G. (ed.): ‘Sheet molding compounds: science and technology’, 257;1993, Munich, Hanser.
2.
SjögrenA.: ‘An approach towards avoidance of pinholes and blowouts in painted SMC’, Internationale AVK-TV, Tagung Baden, Baden, 2002.
3.
NaiduM. S. and KamarajuV.: ‘High voltage engineering’, 378; 1996, New York, McGraw-Hill.
4.
ComteE., MerhiD., MichaudV. and MansonJ. A. E.: ‘Void formation and transport during SMC manufacturing: effect of the glass fiber sizing’, Polym. Compos., 2006, 27, (3), 289–298.
5.
OdenbergerP. T., AnderssonH. M. and LundstromT. S.: ‘Experimental flow-front visualisation in compression moulding of SMC’, Composites A, 2004, 35A, (10), 1125–1134.
6.
YamadaH., MihataI., TomiyamaT. and WalshS. P.: ‘Investigation of the fundamental causes of pinholes in SMC moldings’, Proc. 47th Annual Conf., Composites Institute, Cincinatti, OH, USA, February 1992, The Society of the Plastics Industry, Inc.
7.
NilssonG.: unpublished work;2006, Piteä, Swerea SICOMP AB.
8.
KimK. T., JeongJ. H. and ImY. T.: ‘Effect of molding parameters on compression molded sheet molding compounds parts’, J. Mater. Process. Technot, 1997, 67, (1-3), 105–111.
9.
BoylanS. and CastroJ. M.: ‘Effect of reinforcement type and length on physical properties, surface quality, and cycle time for sheet molding compound (SMC) compression molded parts’, J. Appl. Polym. Sci., 2003, 90, (9), 2557–2571.
10.
Le CorreS., OrgeasL., FavierD., TourabiA., MaazouzA. and VenetC.: ‘Shear and compression behaviour of sheet moulding compounds’, Compos. Sci. Technot, 2002, 62, (4), 571–577.
11.
Le CorreS., DumontP., OrgeasL. and FavierD.: ‘Rheology of highly concentrated planar fiber suspensions’,J. Rhea, 2005, 49, (5), 1029–1058.
12.
LinC. M., WengC. I. and HoC. T.: ‘Anisotropy in sheet molding compounds during compression molding’, Polym. Compos., 1997, 18, (5), 613–622.
13.
MarjavaaraB. D., EbermarkS. and LundstromT. S.: ‘Compression moulding simulations of SMC using a multiobjective surrogate-based inverse modeling approach’, Mech. Compos. Mat., 2009, 45, (5), 503–514.
14.
CostiganP. J., FisherB. C., and KanagendraM.: ‘The rheology of SMC during compression molding, and resultant material proper-ties’, Proc. 40th Annual Conf., Reinforced Plastics/Composites Institute, Atlanta, GA, USA, January-February 1985, The Society of the Plastics Industry, Inc, Session 16E, pp.1–12.
15.
KimD. K., ChoiH. Y. and KimN.: ‘Experimental investigation and numerical-simulation of smc in compression molding’, J. Mater. Process. Technot, 1995, 49, (3-4), 333–344.
16.
RabinovichM., OlsavskyK. L., LeachB., Cabrera-RiosM. and CastroJ. M.: ‘Sheet molding compound characterization using spiral flow’, J. Appl. Polym. Sci., 2008, 109, (4), 2465–2471.
17.
LeT. H., DumontP. J. J., OrgeasL., FavierD., SalvoL. and BollerE.: ‘X-ray phase contrast microtomography for the analysis of the fibrous microstructure of SMC composites’, Composites A, 2008, 39A, (1), 91–103.
18.
DumontP., OrgeasL., FavierD., PizetteP. and VenetC.: ‘Compression moulding of SMC: in situ experiments, modelling and simulation’, Composites A, 2007, 38A, (2), 353–368.
19.
Minitab: ‘One hard-to-change factor answer#1068’Technical support document; available at http://www.minitab.com/en-SE/ support, revised 7 July 2009.
20.
MontgomeryD. C.: ‘Design and analysis of experiments’, 643; 2005, Hoboken, NJ, John Wiley & Sons.
21.
OlssonN. E. J., LundströmT. S. and OlofssonK.: ‘Process study on compression moulding of SMC using factorial design’, Proc. 19th Int. Symp. on ‘Transport phenomena’ (ISTP-19), Reykjavik, Iceland, August 2008, University of Iceland, Paper 179.
22.
LundstromT. S., GebartB. R. and LundemoC. Y.: ‘Void formation in RTM’, J. Reinf Plast. Compos., 1993, 12, (12), 1339–1349.
23.
MerhiD., ComteE., MichaudV. and MansonJ. A. E.: ‘Correlation between sizing formulation and compressive behavior of concentrated glass bundle suspensions’, Polym. Compos., 2005, 26, (3), 370–376.
