There is not any doubt about the future of cars and their propulsion. Everyone hears everyday about the environmental problems related to the internal combustion engines and that we should move to another type of mobility, based on electric propulsion.

After the crisis because of the present global pandemic emergency, these problems are even more important owing to the possible relationship between the ability of the virus to infect and the level of pollution in the environment. So, we should think and manage the transition to the new electric cars and the influence they have on the present surface-processing supply chain.

Indeed, let me say that not until energy resources will be mostly renewable will the problem be solved on a global scale. However, it is true that the quality of the air in urban environments would strongly benefit from the absence of emissions of electric cars. And this is the future of cars. After the intermediary hybrid cars, electric cars will populate the cities!

Nothing bad with that, we know! But someone could wonder what the future is of shot peening in this new car concept. Indeed, the power transmission of electric cars will be different from the present one and the need for high-performance gears will not be a priority. This appears not good for shot peening and allied treatments; however shot peening does not mean just gears, and design for environment does not just mean a shift to electric cars. What is the message?  No need to say that shot peening will be applied to the components that the present cars have in common with new cars: springs are the first example that comes to mind.

But, more than this, we know that every metal or plastic part in a car is obtained by means of a complex manufacturing cycle, such as forging, forming and/or machining. Surface treatments are an important part of this. No matter what way is used to get the desired surface properties and characteristics; surface quality must be created somehow. That is to say, the basic requirements for surface quality must be created whatever the final coating paint or electroplating process is. 

But, let me add than many of the processes used for getting the desired final surface finishing and state are not environmentally friendly; most of the surface coating or painting processes are polluting and there is continuous research about alternative processes. Furthermore, these processes are on the way to being blocked by the authorities.  

Grinding, sand blasting, grit blasting and other mechanical finishing processes are excellent candidates to be part of the new surface-finishing technological cycles. 

So, even if we probably will not need powerful gears anymore, able to resist severe fatigue loads, it is true that new needs are appearing and they require sustainable solutions in terms of energy demand, process materials and final environmental impact.

Indeed, mechanical treatments such as the ones just mentioned and the so called "shot peening allied treatments" are the perfect candidates for that. No toxic waste substance is expected, although lower energy demand is. 

Someone could object that the final surface appearance will not be the same but it is also to be remarked that the surface finishing effects may be adapted to take into account the new priorities. Just what is needed to guarantee the functional behaviour should be respected, and the rest can change, and this means that there is space for new solutions and treatments.

The future is still to be written; however, it is certain that surface finishing will be one of the main aspects of the new automotive era and that surface treatments will be good partners.

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