A new study by researchers at Cranfield University in the UK finds that switching from aluminum to zinc alloys in the production of automotive parts could greatly enhance their longevity and sustainability.

The study, conducted by Cranfield’s Sustainable Manufacturing Systems Center, evaluated the performance of three different alloys (aluminum-A380, magnesium-AZ91D and zinc-ZA8) considering overall product life cycle aspects and process characteristics through a deterministic technique for order of preference by similarity to ideal solution (TOPSIS). Over recent years aluminum alloys have been favored by the automotive manufacturing industry for their lightweight properties and lower cost.

The study, published in the International Journal of Sustainable Manufacturing, suggests that aluminum is frequently chosen ahead of other alloys because of a failure to fully factor the sustainability of the end-product into consideration. When examining sustainability alongside traditional factors such as time, cost and flexibility, Cranfield’s research demonstrated that the zinc rather than the aluminum or magnesium alloys offered the better choice for automotive manufacturers.

The zinc alloy proved to be a more sustainable and higher performing option, when considering measures such as the environmental impact caused by the extraction of the metal and the quality of the parts it produces. Despite the aluminum alloy being a lower cost option, the study found that the zinc alloy also offered better value for money as the parts it creates are likely to have a much longer life than the other alloys.

Previous Cranfield research has demonstrated that the automotive industry’s focus on increasingly lighter weight cars to increase fuel efficiency, often through lightweight aluminum, may not actually be a more environmentally sustainable option.

Aluminum has become the favored material of the automotive industry for its lightweight properties and comparatively low cost. However, our study which looked in depth at sustainability, alongside traditional factors such as time, cost and flexibilty, showed that actually a zinc alloy can be better value for money as well as being more sustainable.

—Professor Konstantinos Salonitis, Head of Sustainable Manufacturing Systems Center at Cranfield

Resources

• Emanuele Pagone; Michail Papanikolaou; Konstantinos Salonitis; Mark Jolly (2020) “Multi-criteria decision-making for the life cycle of sustainable high pressure die casting products” International Journal of Sustainable Manufacturing doi: 10.1504/IJSM.2020.107140