Building better practices for automotive sustainability
Photo courtesy of Hydro

Building better practices for automotive sustainability

The University of Michigan recently announced a $2 million project to study better ways to make recyclable lightweight sheet metal for cars.

May 5, 2021

In 2026, it is estimated that cars will have about 514 pounds of automotive aluminum content, up from 459 pounds in 2020, according to a 2020 market intelligence report by DuckerFrontier.

To make sure manufacturers meet the growing demand, The University of Michigan (UM) has announced a $2 million project to develop easier and more cost-effective ways to make recyclable, lightweight automotive sheet metals.

The project is called The Clean Sheet Project and seeks to develop and establish best practices for material and car manufacturers focused on recycling. The project will focus on energy-intensive aluminum and advanced high-strength steel automotive sheets. However, it could eventually look at plastics, polymers and electric vehicle (EV) batteries, according to UM.

“Transportation and industry are two of the big slices of the pie when it comes to emissions. Manufacturing electric vehicles has been steadily increasing,” says Daniel Cooper, UM assistant professor of mechanical engineering and the principal investigator of the project. “Producing these vehicles means there will be more emissions, so it's important to focus on the making of these vehicles.”

The project has garnered support from various experts in the industry. Half of the project’s funding comes from the U.S. Department of Energy’s REMADE Institute, a public and private partnership to promote sustainable technology adoption.

The project also has some private backers, including Ford, aluminum recycler Novelis, the Institute of Scrap Recycling Industries, the Aluminum Association, Light Metal Consultants and Argonne National Laboratories. Cooper did not disclose the financial breakdown of contributions from these private companies.

A growing market

Two main factors are driving this project, Cooper says. First, electric vehicles would account for 40 percent of new car sales by the end of the decade, according to UBS Investment Bank. Second, by 2030 about 80 percent of scrap demand will be for aluminum sheet, according to Cooper’s research.

Aluminum has become a popular material for car manufacturing because of how lightweight it is. This makes it important for vehicle-mass reduction because it helps reduce carbon emissions for cars, Cooper says.

He says aluminum also is becoming popular because of its thermal properties for EVs and combustion vehicle electronics. Aluminum can also be used to make electric battery trays and components for combustion engines.

Because of these benefits, several automakers have begun using it in manufacturing. Companies like Ford, Tesla and Audi are all using the material for their vehicles, Jinlong Wang, the senior environmental specialist at the Aluminum Association in Arlington, Virginia, says.

Quality metals

According to a 2016 report from the Worcester Polytechnic Institute’s Center for Resource Recovery and Recycling in Massachusetts, 95 percent of aluminum used in a vehicle is recycled.

“These metals are already well recycled,” Cooper says. “The issue is more can we maintain the quality?”

Cooper says that recycled metal products aren’t high quality because it is difficult to obtain pure material to melt down. This is because vehicles contain different metal alloys that are tough to separate during recycling.

This is made more difficult because EVs use copper wiring in their electronics. Recycled steel can crack during manufacturing if it contains 0.1 percent copper, according to UM.

“A lot of it is about how clean you can make your scrap source at the end of life. It’s also about how tolerant you are to contamination,” Cooper says. “You’re not going to eliminate every bit of contaminant. How tolerant you are into processing that back into sheet metal is a big part of this project.”

Setting the standard

Cooper, who has spent 10 years researching metals processing in the automotive industry, says that while previous efforts had sought to make EV components like aluminum sheeting more recyclable, an integrated approach was missing. Cooper hopes this project will allow manufacturers to evaluate the implications of how they make sheet metal, which alloys they are using and what technologies scrap processors need to invest in to maximize end-of-life benefits.

“We will look at the efficacy (capital and operating costs, throughput, energy, yield and resulting purity) of existing and emerging disassembly, separation and refining processes,” Cooper says of the study.

He adds that the study will look at the following recycling processes: steel separation (magnetic, embrittlement, sink-float and heavy-media separation and laser-induced breakdown spectroscopy (LIBS); steel refining such as vacuum distillation, sulfur matte, fluxing and reactive gas evaporation, solidification segregation, slagging and electrorefining; aluminum separation such as hot crush and LIBS; and aluminum refining, such as chlorination or fluoride fluxes, Hoopes process, low-temperature electrolysis, vacuum distillation, electrorefining for magnesium, fractional crystallization, membrane purification cell and super-gravity-aided rheorefining method.

The project will begin in the fall with a two-year timeline. Researchers will use a computer modeling approach to help determine several factors. The model will help them discover how mixed metals can be recycled and find new materials that are more recycling-friendly. The program also will help researchers determine how more recycled materials can be used in high-quality components like aluminum car bodies. 

Researchers also will analyze existing car designs to find out where materials are being used and how. New technologies for separating materials and disposing of old vehicles will also be analyzed, according to the UM.

“This process will help us create design tools for manufacturing companies that will assist them in their design process for alloy use,” Cooper says. “The ultimate idea is to find a way to widen these specifications to increase contamination tolerance and then can we even design alloys that are resistant to contamination sources?” 

Cooper says he also believes that this project could influence the early stages of vehicle design.

Ecological and economic benefits

This study will allow recyclers to plan for the future of automotive scrap flows and new alloy demand and consider the tradeoffs of investment costs versus lost opportunities to enter new higher value markets.

“Some changes could include making investments in new separation and refining technologies and optimal presorting and disassembly before processing with automated high throughput technologies,” Cooper says.

The project’s findings will have two key benefits for car manufacturers using aluminum sheeting in their cars. The first is that it will help companies meet their sustainability goals. For example, Ford plans to make its company carbon neutral by 2050. One of the main ways it plans to do that is by addressing emissions produced by its facilities, according to a news release from the company.

The other key benefit of this project is its financial impact by ensuring companies don’t lose money during production. Cooper says his team’s research will allow companies to recycle scrap metal back into production.

“These sheets of aluminum are significantly more expensive than low-carbon steel,” he says. “If manufacturers can recover these high-quality aluminum sheets, that's going to be a huge benefit for a company’s bottom line.”