Glass Bubbles for Sheet Molded Composites

3M™ Glass Bubbles for sheet molding composites


Sheet molding composites (SMCs) are well known for being more light weight than metals or other types of composite materials. Now, compounders and resin suppliers can produce SMC parts that are up to 45% lighter, enabling ultralightweight composites that replace heavier steel and aluminum body panels, hoods, trunk lids and more. That’s because 3M™ Glass Bubbles – tiny, hollow glass microspheres added to resins in SMC production – are engineered to withstand the requirements of the sheet molding process despite their low density. Best of all, they help enable your parts to meet OEM requirements for Class A paintable surfaces.

Automotive body with each 3M solution shown for interior and exterior applications.
  • 1. Trunk bed

    2. Trunk lid

    3. Sunroof frame

    4. Sunroof curtain

    5. Glove box and interior compartments

  • 6. Engine hood

    7. Front trunk bed

    8. Noise reduction parts

    9. Headlight assembly

  • 10. Front end module

    11. EV battery housing

    12. Door panels

    13. Structural SMC

    14. Side body molding

3M™ Glass Bubbles for sheet molding composites – inside and out

    • Two panels on a scale showing the lightweight panel made with 3M™ Glass Bubbles.

      Exterior components

      Weight reduction: 3M™ Glass Bubbles can enable densities below 1.0 g/cc and a total SMC component weight reduction of 45%, making ultralightweight SMC parts a replacment for metal in more places on the vehicle.

      Class A paintable finishes: While fillers can sometimes affect the final part surface, compounders and resin suppliers can still produce lightweight SMCs with a Class A Paintable finish – making SMCs/BMCs a replacement in many more places on the vehicle.

      Recommended products:

    • Lightweight SMC panels made with 3M Glass Bubbles.

      Interior components

      Weight reduction: 3M™ Glass Bubbles can enable densities below 1.0 g/cc and a total SMC component weight reduction of 40%, making SMC parts a replacement for metal in more places on the vehicle.

      Recommended products:

      Pictured: Lightweight SMC panels made with 3M Glass Bubbles.

Zoomed in shot of 3M™ Glass Bubbles
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For your sample of 3M™ Glass Bubbles for sheet molding composites, click below.


Lightweighting sheet molding composite resources

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ORLANDO – May 7-11, 2018 – National Plastics Expo, Booth #S27153 – As automotive manufacturers look to improve fuel economy and battery range for electrification, material lightweighting without compromising mechanical integrity is vital. Metals, although lightweight, can come with indirect processing and manufacturing costs and may become even more expensive with the uncertainty surrounding global metal supply. Sheet molded composites (SMCs) are a viable alternative to metals in certain applications, while still achieving the desired physical properties. 3M today introduces Glass Bubbles S32HS to help OEMs achieve up to a 40 percent weight reduction of composite parts, at a density below 1.0 g/cc, while still enabling a class A paintable finish. This innovation makes SMCs an attractive option in automotive design for OEMs.

“With the trend toward electric and high efficiency cars, reducing overall vehicle weight is key to staying competitive,” said Ray Eby, vice president of 3M Automotive Electrification. “A typical automobile has about 660 lbs. of composite parts. With ultra lightweight SMCs enabled by our glass bubbles, OEMs can significantly improve a vehicle’s energy usage, while saving money– one less bump in the road in the race to automotive electrification.”

For many years, 3M has partnered with the automotive industry to enable weight reductions for major automotive manufacturers. By replacing conventional fillers, these hollow glass microspheres can reduce the weight of molded parts without sacrificing strength or aesthetics. For the first time, 3M has been able to break the density barrier, making ultra lightweight SMCs more competitive to steel and aluminum, opening up new possibilities for the material mix in automotive applications.

“Our customers continue to challenge us to lower the density and weight of fiberglass reinforced material systems to support their automotive lightweighting efforts,” said Terrence O’Donovan, vice president, marketing and sales for Core Molding Technologies. “A density of 1.0g/cc or below has long been a goal, while still enabling a Class A finish. Using 3M Glass Bubbles helps enable us to meet our customers’ expectations.”

3M glass bubbles are an established lightweighting technology used in enabling lightweight sealants, injection molded parts and SMCs. 3M continues to be at the forefront of automotive lightweight material innovation with the launch of Glass Bubbles S32HS.