Compared to other direct liquid processes, Wet Compression Molding (WCM) enables faster cycle times, and thus higher productivity. The main automotive application is for structural parts of the body-in-white, such as spars. Huntsman offers resin systems specifically designed for WCM, and our innovative DFCM process greatly improves the quality of the composite parts versus standard WCM.
In applications where structural composite processes such as HP-RTM may be too expensive, Huntsman’s Dynamic Fluid Compression Molding (DFCM) technique offers not only reduced cost, but also the potential for significant performance benefits and enhanced design freedom. In combination with our latest dedicated resin system, our novel DFCM process reduces part-to-part cycle time to just one minute—one third the lowest cycle time achievable with HP-RTM—while mitigating the drawbacks associated with standard WCM.
Glass transition temperature (Tg):
120 - 130°C
Cure time:
2 min at 115°C (HP-RTM)
1 min at 140°C (WCM)
Suitable for:
Fast cure solution offering enhanced processing (1 min injection window at 115°C), reduced curing cycle and improved toughness versus state-of-art technology (ARALDITE® LY 3585 / XB 3458). High clarity system for production of cosmetic parts.
Glass transition temperature (Tg):
110 - 120°C
Cure time:
30 s at 140°C
Suitable for:
Very fast cure solution developed to improve productivity and meet requirements of structural automotive parts made by Wet Compression Molding (WCM) and Dynamic Fluid Compression Molding (DFCM).
Thanks to our broad experience with direct liquid processes, Huntsman is able to design resin systems that meet the processing requirements of WCM and performance targets for the final parts. In addition, our simulation capabilities help customers to significantly decrease development time (resin system selection, process parameters determination, process safety).
Our leading composite expertise, broad product range and unique simulation capabilities can reduce development cycles by up to 50 %.
Wet Compression Molding is significantly faster than HP-RTM for two reasons. First, there is no injection phase—the resin can be applied to the preform out of the mold, reducing mold occupation time. Second, the impregnation of the preform occurs perpendicular to the fiber, so lower-latency resins can be used, enabling reduced curing time.
Standard Wet Compression Molding processes tend to deliver equivalent or higher volumetric fiber content, but a higher level of voids, than HP-RTM. This translates to lower mechanical performance and lower quality of parts. These drawbacks are mainly due to the absence of hydrostatic pressure on the resin during and after mold closure.
Huntsman’s engineers have developed molds that allow a dynamic hydrostatic pressure to be applied to the resin just after the air has been removed from the preform. Our unique DFCM process allows reaching much higher fiber-in volume resin content than HP-RTM (up to 65% versus 50%). The new process also reduces void content of laminates in comparison to conventional Wet Compression Molding. It delivers typical porosity content of less than 1%, making it comparable to HP-RTM or autoclave prepregs.
Structural resin systems used for HP-RTM can be used for Wet Compression Molding (WCM), but Huntsman's WCM-specific resin solution offers very low viscosity, and much faster reactivity than HP-RTM resins. ARALDITE® 3031 resin / ARADUR® 3032 hardener allows curing time of less than one minute—a time savings of more than 50% compared to state-of-the-art HP-RTM resins.
