The Impact of Brake Wear on Emissions in Urban Environments
Air quality in major cities is benefiting from improvements in emissions technology associated with electric vehicles (EVs). However, brake wear contributes up to 55% of all non-exhaust traffic-related emissions in high-density urban environments, including harmful carbon-based particulate matter. This is a significant issue for both combustion-based vehicles and EVs. Non-exhaust emissions are now the dominant source of particulate matter from road transport in the UK. Brake emissions, particularly in the PM10 range, can have severe health effects as these particles can reach the outer areas of the lungs. The European Environment Agency has reported that exposure to fine particulate matter above health guidelines has resulted in premature deaths in the EU.
The Need for Dust Busting Brake Coatings
As stricter emissions standards are being proposed, there is a greater focus on non-exhaust emissions. A study by Emissions Analytics found that the greater the vehicle mass and propulsion torque, the greater the amount of particulate emissions. Electric vehicles, with their heavier battery weight, are not exempt from this issue. While ceramic brake pads create less brake dust than metallic ones, they have limited functionality until they are warmed up. This makes them impractical for everyday consumer cars. Coating brake discs with a combination of a metal alloy and ceramic powder can provide a corrosion-resistant solution that reduces resistance and minimizes emissions.
Thermal Management Challenges in Electric Vehicles
As electric vehicles become more powerful and incorporate larger batteries, efficient cooling systems are needed. Advanced heat sinks, which transfer heat from the engine to the external environment, are typically made of a hybrid of copper and aluminum. However, traditional materials have their limitations. Copper is heavy and reduces driving range, while aluminum cannot be soldered efficiently. By spraying a copper coating onto an aluminum substrate, heat sinks can benefit from the heat conductivity of copper and improved heat transfer while still maintaining weight efficiency.
Next Generation Cold Spraying for Automotive Applications
Cold spraying is a material deposition technique that uses high-pressure gases to propel tiny metal particles onto a substrate. This process creates a ductile and oxidation-resistant coating. However, the high temperatures required in the gas stream make the manufacturing process dependent on various factors, including a stable and reliable gas flow. Linde Technologies and Impact Innovations have developed the Linspray Connect system to ensure a reliable gas flow with minimal variation. This system monitors process parameters and can automatically respond to incidents, ensuring a uniform coating and high product quality.
The Benefits of Enhanced Cold-Spraying Capabilities
Enhanced cold-spraying capabilities allow automotive manufacturers to cost-effectively meet new particulate emissions regulations. This technology also improves brake corrosion resistance, providing a competitive advantage for OEMs. For EV drivers, it means their choice of electric car can make a real contribution to reducing air pollution while enjoying greater driving range and less maintenance.
About the Authors
Werner Krömmer is responsible for Business Development in the Manufacturing Industry at Linde Technologies. Paolo Kirchpfening is the Global Commercialization Manager at Linde Technologies.
Analyst comment
Positive news:
– Enhanced cold-spraying capabilities can help automotive manufacturers meet emissions regulations and improve brake corrosion resistance.
– Electric vehicles with copper-coated aluminum heat sinks can have improved cooling systems while maintaining weight efficiency.
Negative news:
– Brake wear contributes a significant amount of non-exhaust traffic-related emissions, including harmful carbon-based particulate matter, in urban environments.
– Exposure to fine particulate matter from brake emissions has resulted in premature deaths in the EU.
Neutral news:
– Ceramic brake pads create less brake dust than metallic ones but have limited functionality until warmed up.
As an analyst, the market for cold-spraying technologies and copper-coated aluminum heat sinks is expected to grow as automotive manufacturers strive to meet emissions regulations and improve brake performance. However, there may be challenges in implementing these solutions due to practical limitations and the need for further research and development.
