At IRDL, Marcos Lopes Leal Junior has developed a method to optimize shape memory actuators in the automotive sector.
Marcos Lopes Leal Junior, chercheur·e au sein de IRDL (Institut National Polytechnique de Bretagne).
Thèse soutenue en 2024 à l'école doctorale Sciences de l'ingénierie et des systèmes (Nantes Université).
Référencée dans le réseau ABES/STAR, cette thèse répond aux critères de rigueur de l'enseignement supérieur français.
The automotive industry is undergoing significant transformation, seeking to reduce its carbon footprint while improving vehicle performance. This quest for sustainability is accompanied by a necessity for innovation, where each component must be rethought to meet current environmental challenges. Shape memory alloy (SMA) actuators represent a significant technological advancement in this context. Indeed, these devices allow for a weight reduction of 40% to 90% compared to traditional actuators, which directly translates into better energy efficiency and enhanced vehicle performance. For example, in the context of vehicle electrification, every gram counts, and the use of SMA can play a crucial role in optimizing electric propulsion systems.
However, despite these undeniable advantages, the adoption of SMA actuators in the automotive industry is hindered by significant technical challenges. One of the main obstacles lies in understanding the thermomechanical behavior of SMAs under cyclic operational conditions. Indeed, these materials react differently depending on temperature variations and mechanical stresses, complicating their integration into complex systems. Fatigue testing, for example, is essential for assessing the durability of actuators, but it requires precise design methods to ensure their long-term reliability.
Marcos Lopes Leal Junior's thesis proposes a multidisciplinary approach to overcome these obstacles. By combining experimental observations, electrical analyses, and multiphysics modeling, this research aims to establish suitable design methods to ensure the reliability and durability of SMA actuators. The results obtained so far are promising, with nearly 200 actuators integrated into vehicles, contributing to improved user comfort and safety. For example, the integration of these actuators into power steering systems not only reduces vehicle weight but also enhances driving responsiveness and precision.
The strategic recommendations arising from this research include the development of additional tools to better control the factors influencing the performance of SMA actuators. This could involve creating performance databases, allowing engineers to better anticipate the behavior of SMAs under varied conditions. Furthermore, establishing suitable fatigue criteria is crucial for transforming the use of SMAs in the automotive sector, promoting lighter and more efficient designs. Indeed, a better understanding of SMA fatigue could extend their lifespan and optimize their use in critical applications.
It is essential to consider how the automotive industry can leverage these advancements. Decision-makers must question the necessary investments to integrate these technologies into their manufacturing processes and the partnerships to be established to maximize their impact. For example, collaborations with universities and research centers could facilitate knowledge sharing and accelerate the development of innovative solutions. Collaboration between researchers and industry is crucial to advance this technology and meet market demands, particularly regarding safety and performance.
In conclusion, the integrated approach proposed by this thesis could not only enhance vehicle performance but also contribute to a transition towards more sustainable mobility. SMA actuators could become a key element in the design of tomorrow's vehicles, combining lightness, efficiency, and durability. At the regional level, particularly in Benin and other West African countries, the adoption of these technologies could also stimulate local innovation and strengthen the competitiveness of automotive industries. By integrating sustainable solutions, countries in this region could not only address environmental challenges but also create jobs and promote economic development. Thus, the future of the automotive industry could be not only greener but also more inclusive and beneficial for society as a whole.
Données clés
- 200 : nombre d'actionneurs SMA intégrés dans des véhicules, illustrant l'application pratique de la recherche.
- 40% à 90% : réduction de poids par rapport aux actionneurs conventionnels, impactant l'efficacité énergétique.
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Sources et accès
Marcos Lopes Leal Junior. Méthode de conception et de dimensionnement en fatigue d'actionneurs à base d'Alliage à Mémoire de Forme pour des applications automobiles. Physique [physics]. École Nationale d'Ingénieurs de Brest, 2024. Français. ⟨NNT : 2024ENIB0001⟩. ⟨tel-04625221⟩