Q&A: Why Can’t Composites Get Traction in Automotive?
Hamid Kia, member of the Materials Tech Team, is the lab group manager for polymer composites at GM
Hamid Kia is the author of more than 40 published papers and has more than 25 patents to his name. He is a participant at the United States Council for Automotive Research LLC (USCAR), a joint venture company formed by Chrysler Group LLC, Ford Motor Company and General Motors Company (GM) to support and facilitate collaborative research. He is on USCAR’s Automotive Composites Consortium (ACC) Board of Directors, serving as chair in 2009. He is also a member of the Materials Tech Team (MTT) and is the lab group manager for Polymer Composites at GM.
How is USCAR structured?
USCAR is the collaborative automotive technology research organization of the three U.S. automakers. At USCAR, we cover a wide range of activities from fuel cells and hydrogen storage, to vehicle electrification and advanced battery R&D, vehicle lightweighting, safety, manufacturing and environmental issues. USCAR also covers a range of materials, such as the Automotive Composites Consortium (ACC) group. OEMs and developers, selected from among automotive suppliers and universities all contribute R&D resources and cost sharing, which are then matched by the U.S. Department of Energy (DOE) through the FreedomCAR and Fuel Partnership program. In addition, the DOE also funds materials R&D at the national laboratories, particularly in carbon fiber.
What is the ACC’s objective?
The ACC itself has a long-range goal of reducing the weight of vehicles by as much as 50 percent while maintaining affordability, all with an eye on increasing recyclability. Our approach is to develop high-risk advanced polymer composites, with a primary emphasis on structural and semi-structural applications. We do technology development, which requires us to pool resources from the three OEM owners of USCAR, suppliers, government and others to develop and improve technologies useful in automotive applications.
How is the ACC structured?
We have three working groups within ACC. One addresses materials and processes, another deals with application development, and a third focuses on technologies related to predicting performance of molded components.
What properties of composites interest you?
Within thermoplastics, we’re focusing on direct compounding for compression and injection molding. We also look at thermosets, carbon fiber, glass fiber, liquid molding and natural fibers. Bonding issues are also of interest to us. When there are bonded composite body panels, you can overcome the bond line read-through by increasing the thickness of the exterior panel. But when the goal is to reduce mass by using thinner and stronger panels (such as carbon fiber composites) then the bond line read-through becomes the bottleneck, which is what we are working on in ACC.
What applications are you focusing on?
Currently, we’re focusing on the composite underbody. Based on the latest math modeling we have done, we can save 15 kg over an optimized steel component. We can also reduce the number of components from 16 down to one or two, which is a significant parts consolidation. Another area we are focusing on is composite seats. Where the underbody is made of glass fibers and glass fabric sheet molding compound materials, the seats are made of long fiber thermoplastics. The weight savings would be in the range of 2.5 to 3.5 kg depending on the type of seat.
What are some of the challenges with predicting performance?
There are a lot of variables to consider; from verifying and validating what has been predicted, to being able to design test methodologies that match the definition of modeling. When you’re modeling, you make assumptions for forces applied to components. It’s not easy to do tests so they overlap and simulate assumptions. It has to be mastered for every type of testing we do. For instance, one activity that ACC advises national labs on is predicting the flow of thermoplastics in a tool as well as the performance of molded component through FEA analysis, so you don’t have to make the tool and consistently redesign the tool. The science of predicting the performance of molded composites is a major enabler in reducing the cost of the finished parts.
How does USCAR interact with the composites industry?
In every aspect of composites, it’s not easy to find suppliers. One of the goals we have is to develop suppliers, because one of our big issues is lack of a sufficient number of suppliers. We used to have a group of more than 10 suppliers, but that’s now down to two or three because the economy has taken a hit on automotive. Any time we have gotten an application, there has to be a supplier attached to it, working with us and learning with us, so that when the research is done, the supplier is prepared to manufacture the component.
What trends have you noticed over the past year?
We see more emphasis on carbon fiber because lightweighting is becoming more important. The dollar-per-pound saved related to mass savings is going up because companies are more willing to pay more up front. Another interesting trend is the use of natural fibers, which relates to going greener and less dependent on oil. The need to go into renewable sources has been driving more emphasis on natural fiber and developing composites.
Is the green movement a fad?
If one wants to use natural fiber in its natural state, it would be a fad. However, there are current projects that focus on reducing the moisture absorption of natural fiber to make low-cost green composites. From that point of view, it fosters more research on eliminating those kinds of issues, and if that is done, it will have a lasting impact.
Why are composites largely relegated to niche models?
Very often, because the industry cannot guarantee quality and performance of composites from the get-go, the OEMs end up using steel as the mainstream design and composites as an option. However, then the design becomes based on steel and a design that is good for steel application often causes failure in composites because of the way the components interface with each other.
How can the composites industry ensure performance and quality?
In order for the industry to be competitive, it has to work with the OEMs at the time of the design of the vehicle so that the design is for composites, not for sheet metal, and then deliver what they promised through the life of the vehicle.
What other issues must the composites industry confront?
One of the issues is cost. Subject to variations of oil prices, long-term commitment to pricing has become an issue for suppliers. They need to come up with strategies to make a commitment to the cost of a component and the consistency of its quality. The OEMs can only allocate a certain amount of money, and that doesn’t necessarily go up every year.
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