In its new report Chasing Cars: Can Composites Catch Up to Steel?, Lux Research states that the accelerating demand for more fuel-efficient cars has raised hopes that car makers will accelerate their adoption of lightweight automotive composites. As an alternative to steel and aluminium, polymer composites can lower overall vehicle weight and help reduce fuel consumption. Yet, despite their potential benefits for consumers and the environment, composites are unlikely to replace steel except in applications where they reduce manufacturing costs for the car maker, the report says.

“The conventional wisdom that auto makers will adopt composites solely for weight reduction misses the mark,” claims David Hwang, an analyst for Lux Research and the report’s lead author. “In reality, composites will find the most use in places where they help cut manufacturing costs, such as in low-volume production and electric vehicles.”

The study surveys the factors promoting and impeding the adoption of composite materials in the automotive industry, examines their potential to replace metals as the dominant material in cars, and identifies technologies in development that could potentially change how composites compare with metals in the future.

In preparing its analysis, Lux Research surveyed leading auto makers and composite material suppliers regarding factors that would most likely accelerate or slow adoption of composites in automotive design. The report’s key findings include the following:

  • Powertrain improvements and high-strength metals offer cheaper routes to efficiency. Despite their potential to lower overall vehicle weight, composites lag behind more economical solutions for driving down fuel consumption. Improvements to the drivetrain, like adding turbochargers or hybridisation, can improve fuel efficiency up to 50%, while aluminium and high- and ultra-high-strength steel can lower weight. This can be accomplished without imposing changes to existing production, supply and recycling infrastructure, meaning composites will need to leverage benefits apart from fuel-efficiency to find adoption.
  • Composites are actually cheaper than steel at low production volumes. Although composites will see some success in high-volume applications with sheet moulding compound (SMC) body panels, most growth will be derived from low-volume production where part consolidation grants composites a cost advantage over steel. Attractive applications include complex non-structural and semi-structural internal components, like front-end modules and seat frames.
  • Advanced material technologies can help composites stage a comeback. New nanoparticle additive technologies, high-throughput moulding processes for structural components, and bio-based materials could drastically change the way composites measure up to steel – if and when they emerge from development.