I recently attended the ICSP15 conference at Purdue University (Indiana, USA). Apart from listening to very interesting presentations and visiting the amazing Indianapolis Motor Speedway Museum, I also had the chance to talk with academics, engineers, and technicians from several countries. I had the impression that many of them are concerned about the possible consequences of the diffusion of electric vehicles (EVs) in the global market.

Indeed, the rapid growth of EVs is reshaping the automotive industry, driving demand for innovative technologies that improve efficiency, reliability, and safety. However, due to the different architecture of EVs, some suppose that the shift from ICE cars to EVs could reduce the market for shot peening. Is this true or even to be expected?

One of the main concerns is related to gears. Although many EVs use simpler gear systems than traditional cars, high-speed electric motors demand gear teeth that can endure extremely high rotational speeds and torque fluctuations. It is well known that shot peening increases the fatigue strength of gears, reducing the risk of pitting and surface cracking. Therefore, I expect that shot peening will continue to be used to improve these components.

Another important aspect is chassis weight reduction, which is crucial for improving EV range. Aluminum alloys and advanced high-strength steels are increasingly used in frames and suspension components. However, these materials can be prone to fatigue damage. Shot peening introduces compressive stresses that significantly increase fatigue resistance, allowing designers to use thinner or lighter components without compromising safety.

And what about battery enclosures and safety structures, which must be protected against vibration, impact, and thermal expansion? The housings, often made of aluminum, can develop microcracks under repeated load cycles. Shot peening and allied processes can also be applied to these components.

Then, there are other components that will continue to be used in EVs: suspension springs, bolts, and other fastening elements remain critical in electric vehicles, and shot peening has long been the standard for increasing the lifespan of these parts. Its importance remains undiminished in EV design.

What I would like to emphasize even more is that EV manufacturing increasingly relies on additive manufacturing (3D printing) for prototyping and even for the production of complex parts. However, such components often exhibit poor surface finish and high residual tensile stresses. Shot peening is an effective post-processing method that improves surface quality, mitigates defects, and ensures higher fatigue resistance.

I am also confident that the attractive aspects of shot peening compared to other surface treatments will make a difference: it does not require chemical baths or high energy input, making it compatible with the sustainability goals of EV production. Moreover, it can be applied to a wide range of materials, is cost-effective, and can be combined with other processes—such as hard coatings or anodizing—to further enhance performance.

As EV technology continues to evolve, I am optimistic that shot peening will remain a vital tool in ensuring that electric vehicles meet the demanding expectations of both consumers and regulators.

Shot Peening in the Automotive Industry

by Mario Guagliano

Contributing Editor MFN and 

Full Professor of Technical University of Milan

20156 Milan, Italy

E-mail: mario@mfn.li