Questions about Thermoset Composites?

IDI Composites International making noise in the quiet revolution of electric cars


Electric cars and thermoset composites are being made for each other.
More specifically, IDI Composites International is a leading developer of a new generation of strong, light thermoset composite materials. Designers and auto manufacturers increasingly use them instead of traditional metal and steel parts. For one reason: thermosets weight 35 percent less than steel of equal strength. And every pound of decreased weight -- without losing strength -- permits smaller and lighter batteries so electric cars can go farther before drivers must plug them in.

IDI has led the thermoset composite industry for 35 years. Their products are commonly found in kitchens and yet reach all the way to the International Space Station. IDI now supplies worldwide markets with a diverse line of strong, durable thermoset sheet molding compounds (SMC's) and thermoset bulk molding compounds (BMC's).

Before listing the many advantages of IDI's SMC's and BMC's for electric cars, let's look at a major one: thermoset composites do not conduct electricity. For electric cars driven by powerful batteries, thermosets are ideal for electrical, physical and heat-shielding components such as battery enclosures.

IDI's attention to detail and willingness to innovate create composites that are becoming material of choice for a wide range of automotive and truck parts. Consisting of fiber reinforcement (for strength and stiffness) in a polymer resin, thermoset BMCs are excellent for mold-ability and SMCs are great for surface strength and appearance. They are used for exterior body panels, headlamp and tail light housings, interior structure and cosmetic components.

IDI continues its workhorse attitude toward developing and bringing new materials to designers and engineers who are focused on increasing the electric car's reliability, geographic range and hauling capacity.

For example, IDI engineers developed IDI AV-206 SMC to resist oil, solvent and salt sprays that commonly eat away at steel and aluminum vehicle components. The material weighs 35 percent less than steel with the same tensile strength. When there is trouble on the road, panels made of AV-206 SMC resist collisions better than metal. And, where metal panels permanently deform on impact, thermoset panels can spring back to their original shape.

Thermosets enjoy other advantages, such as:

  • High thermal stability: thermoset parts maintain dimensional stability when exposed to engine heat and summer temperatures and are even stronger at lower temperatures

  • Great surfaces: thermosets are capable of looking like a steel surface

  • Shorter cycle times: by slashing the number of parts in finished assemblies, tooling major thermoset auto panels takes half as long as tooling for major steel body panels.

  • Thermosets also cost as much as 70 percent less than current-generation thermoplastics and automotive steel. They enjoy an even greater cost advantage over steel's other lightweight rival, aluminum.


The idea that you could plug in a car overnight and then swoosh quietly down the street the next day is not new. It has been around since before there was an electric grid to plug into.

Now, evolutions in materials, public perception and official policy point to more electric cars down the road. In one modest estimate from an auto industry insider, by 2020 fewer than 4 percent of the vehicles will be electric. That would mean 10.1 million electric vehicles on U.S. highways.

"Ten million electric vehicles is a significant number, and that market share will only grow," says Paul Rhodes, IDI vice president for marketing and sales. "It's inevitable that more people will drive electric cars. And we have the materials to help grow that market."

Designers, engineers and OEMs looking for great material performance, durability, attractiveness and economy are finding them in IDI Composites International's thermoset sheet molding compounds (SMC's) and thermoset bulk molding compounds (BMC's). They are engineered for performance.

About IDI Composites International
IDI Composites International (IDI) is the premier global custom formulator and manufacturer of thermoset molding compounds for channel partners and OEMs. The company provides customized polyester/vinylester-based bulk molding compounds (BMC), sheet molding compounds (SMC), and a new line of Structural Thermoset Composites (STC®) that are manufactured in both sheet and bulk formats for the most demanding applications in markets such as Military & Aerospace, Transportation, Safety, Medical, Electrical, Oil & Gas, Alternative Energy, and Marine. Click to learn more about Structural Thermoset Composites.

Headquartered in a 120,000 square foot manufacturing facility and research center in Noblesville, IN (USA), IDI has a strong presence in the international thermoset composites market. With more than 50 years of leadership experience, IDI works closely with customers to identify the optimal thermoset molding compound for each application. The company has substantial R&D resources, plus excellent chemical engineering, ISO-certified manufacturing, and comprehensive quality control.

Thermoset Composites for the Electric Car Industry