The automotive industry is facing enormous challenges in term of sustainability, with the need to decrease emissions, resource depletion, energy consumptions and the overall impact on ecosystems throughout the whole life cycle of a product. The transport sector is responsible for about 55% of fine particulate emissions (PM2.5) globally, of which 21% currently derives from wear particles of brake and tires (1). It is a critical sector to reach the goal of climate neutrality within 2050 limiting global warming to 1.5 degrees Celsius above pre-industrial level and materials emissions represent a large portion of the overall emission of a vehicle. (2) In the future friction materials needs to be further and further environmentally friendly to achieve the net zero-carbon. Life Cycle Assessment of currently employed materials needs to be performed in order to define a baseline from which improvements need start and to highlight hot-spot critical materials in formulations. Life cycle Assessment is a recognized methodology to evaluate environmental impacts of products, following ILCD book methodology and ISO 14067:2018 (3), in our analysis we implemented ad Cradle-to-Gate approach, considering materials from their extraction and/or synthesis to the production of the mix, considering 1 kg of friction material as a functional unit. Production of the pads was not taken into account, as the objective of the study is the highlight of critical materials that need to be controlled in new formulations. Our first results highlighted that, of all materials present in brake pads (4), aramid fibers, metallic tin, potassium titanate and zirconium oxide are materials with higher global warming potential in friction materials formulations. 1. Brake wear particle emissions: a review. . Grigoratos, T. M. 22, 2015, Environmental Science and Pollution Research, pp. 2491–2504. 2. The Zero-carbon car: abating material emissions is next on the agenda. Hannon, Eric , et al. s.l. : McKinsey&Company, 2020, Sustainability Practice. 3. General Guide for Life Cycle Assessment : Provisions and Action Steps. Centre., European Commission. Joint Research. s.l. : Institute for Environment and Sustainability, 2010. 4. Review of automotive brake friction materials. Chan , D and Stachowiak , GW. 2004, Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering., Vol. 218(9), pp. 953-966.

Ms. Rosamarie Depetris, Sustainability Specialist, ITT Motion Technologies; Mr. Agusti Sin, X, ITT