David Stewart has been working in the automotive industry for over 20 years, taking technology out of labs and applying it to mass production environments. He owns a research firm, Stewart Automotive Research, and was just named chief executive of Zoltek Automotive, a new subsidiary from the carbon fiber supplier.

David Stewart, chief executive of Zoltek Automotive, speaks to CM Magazine on the growing use of composites

David Stewart, chief executive of Zoltek Automotive, speaks to CM Magazine on the growing use of composites

Zoltek’s CEO is quoted as saying carbon fiber is easier to use in wind energy than automotive. What makes automotive tougher to work with?

The volume requirements involve very different requirements on the manufacturing process. Cycle time is important, and the part geometry is substantially more complex. The chemistry of the curing process for thermosets needs to be tailored to the faster cycle time requirements. For preforming, getting the fibers into the appropriate alignment with the part geometry and structural requirements is a very different process for smaller parts with more curvature as compared to the structural parts in wind blades.

Why did Zoltek form this subsidiary?

The primary factor was renewed interest in automotive composites from the OEMs. Several OEMs have announced production programs where they’ll be delivering production vehicles that utilize lightweight carbon fiber materials. There are a few examples in production right now. In lower volumes, Tesla has carbon fiber body panels; in higher volumes, BMWs are being manufactured with carbon fiber structural and exterior body panel components. It has given some confidence to other OEMs that there’s a place for these materials in low-volume niche manufacturing and higher-volume production applications.

Which American OEMs are more likely to use composites?

That’s a tricky question. They all have equivalent incentives. I can’t comment on any of their individual development programs because of their proprietary requirements. I will say that GM and Ford have the development budgets that allow them to pursue these opportunities. It is worth noting that the latest wave of gasoline price increases and changes in the regulatory environment has led to that renewed interest among the OEMs in composites.

What are some of the biggest challenges OEMs have working with composites?

Composites are a challenge for material substitutions because the technology required to manufacture composites differs so much from the traditional materials they replace. The design and manufacturing infrastructure both change and that makes it challenging for existing capital industries to change over from one material to another. There’s such a huge investment in the existing way of doing things in the engineering, design, testing, quality control, etc.