Core Molding Technologies Inc.’s sheet-molding compound (SMC) material reached 0.98 specific gravity, less than the density of water, meaning the material would float. Hydrilite SMC exhibits mid-range mechanical performance and a high-quality surface appearance. Nearly 50% less dense than standard SMC materials and 17% less dense than Core’s other lightweighting material solutions – Airilite and Econolite SMC systems that test at 1.18 specific gravity.
“Customers continue to challenge us to lower the density of fiberglass-reinforced material systems to support their lightweighting efforts,” says Terry O’Donovan, vice president of marketing and sales for Core Molding Technologies. “A density of 1.00 specific gravity, equivalent to the density of water, has long been seen as a practical limit by formulation chemists throughout the thermoset industry. To be the first to crack that barrier and achieve a functional system is a high achievement for our development team and a meaningful product advance for our customers.”
Hydrilite SMC is formulated with a high-performance resin system and is reinforced with 41% glass fiber by weight.
“The use of glass fiber results in a material system considerably more economical than those based on carbon fiber, while achieving even lower density,” O’Donovan says. Hydrilite SMC achieves nominal tensile strength of more than 75MPa and impact strength of 850J/m. Both results are on par with Core’s standard-density reinforcement-grade SMC formulations. This performance, along with other mechanical properties of the system, make it suitable for a broad range of lightweighting applications requiring a combination of strength and high appearance. A commercial program using Hydrilite SMC is undergoing customer qualification, and other applications are in development.
“A molded product that weighs 100 lb in standard-technology SMC, would weigh only 51 lb in Hydrilite SMC. Yet, Hydrilite is probably not the stopping point. We are currently working to develop a full Class A version of the product, while retaining the 0.98 specific gravity density and adequate mechanical performance,” O’Donovan adds.
Core Molding Technologies Inc.
CAD/CAM software upgrades
Tebis America Version 4.0 Release 3 software includes toolbars and menu panels that can be easily docked to the edge of the application window, a software interface that allows users to learn to operate it with less effort, and a new project dialog with the most recently used files displayed immediately after the program is started.
Tebis engineers have also improved the display of wire-frame models and isolines. The user is often confronted with the problem of many isolines, which can make the component view unclear on the screen. The software also automatically breaks up assemblies and complex files into multiple individual files.
Release 3 provides improved algorithms that generate transitions for 4-edge surfaces. Users can adjust approximation tolerances and control generated radius runouts and theoretical edges more efficiently. When generating surfaces with constant curvature, Release 3 supports symmetrical areas and provides better management of input parameters when using optimization functions.