The braking system is a crucial element in automotive safety. For the braking mechanism to function effectively, the brake pad’s durability as well as quality are crucial aspects to consider. A brake pad is a feature of a vehicle that holds the wheel rotation so that braking can occur smoothly and is part of the braking system component in addition to the master cylinder, wheel cylinder, and hydraulic control system.
Brake pads have sparked a lot of research interest because of their nature and impact to the environment. Asbestos, which is harmful to human health, is a raw material that is recently being widely used as a material mixture for the manufacturing of brake pads. It is hydrated magnesium silicate that possesses good characteristics, including strength, durability, flexibility, and resistance to corrosion, heat, and fire. Since it is plentiful, asbestos is a low-cost material. Its adaptability has resulted in its inclusion in various goods across various industries revealed in a research titled “Overview of the Important Factors Influencing the Performance of Eco-Friendly Brake Pads” by Professor Dr. Tezara Cionita.
“Based on the International Agency for Research on Cancer (IARC) and World Health Organization (WHO), asbestos is carcinogenic. The dust produced by these materials can cause cancer in the lungs, therefore, the application of this material is prohibited in the automotive industry and others. While its mechanical properties are needed to be maintained, it is necessary to develop new materials to replace asbestos as a friction material due to the side effects it brings,” said Dr. Tezara from the Faculty of Engineering and Quantity Surveying at INTI International University, Nilai.
Many efforts have been made by researchers to find other natural alternative materials to replace the use of asbestos. Natural materials that have received much attention and research include coconut fibre, wood powder or flour, bamboo fibre, shell powder, and more[1].
In the research jointly conducted with academicians from other universities in Malaysia and Indonesia, Dr. Tezara shared, “Natural fibres have many advantages compared to synthetic fibres due to their low density, inexpensive, recyclable, biodegradable, renewable, relatively high strength, and stiffness characteristics.”
Professor Dr. Tezara Cionita, from the Faculty of Engineering and Quantity Surveying at INTI International University, Nilai, revealed that coconut shells have the potential to be employed as a non-asbestos friction material for brake pads in lightweight vehicles like motorcycles.
She further stated, “Aside from these benefits, increasing environmental concerns and rising petroleum consumption levels are driving the entire world to use more sustainable natural resources. Therefore, natural fibres are rising as reinforcing fibres for composite materials in the automotive, furniture, packaging, and construction industries due to these advantages.”
According to the research, biomass produced from agricultural activities like plant and animal waste products, and agricultural residues are trending materials for the manufacturing of brake pads as they are commercially acceptable, besides being environmentally friendly.
“Numerous researchers have employed a wide range of material selections, formulations, compositions, optimization, and processing techniques through multiple research designs to implement asbestos along with agricultural-based materials in brake pad productions,” Dr. Tezara expressed.
For example, coconut shell waste. Coconut shells do not contribute any value except as an alternative fuel. Previously, coconut shells were burnt as solid water disposals which release carbon dioxide and methane emissions into the breathing air[2]. Dr. Tezara elaborated, “But as time progressed, it is understood and learnt that coconut shell wastes have many sustainable advantages like better physical properties and a high compressive strength, which is dependent on the composition of the coconut shell. Based on these characteristics, coconut shells have the potential to be employed as a non-asbestos friction material for brake pads in lightweight vehicles like motorcycles.
She concluded, “Various agricultural wastes are researched and employed as asbestos substitutes in brake pads over the years. Thus, all along, it is found that the brake pads developed with agricultural wastes perform almost the same as the brake pads developed with asbestos. We are working hard as a team to further disseminate our research findings to the wider audience to educate them about the use of agricultural waste in brake pads and how it reduces environmental pollution and health risks.”
[1] https://www.bendix.com.au/bendix-news/environmentally-friendly-brake-pads-for-ev-hybrid-vehicles-the-latest-innovative-development-from-bendix
[2] https://staff.futminna.edu.ng/MEE/content/journal/PF1381/43.pdf