A broad portfolio of renewable materials is available now that can help the automotive industry reduce its carbon footprint. Many of these new materials exceed the performance of traditional plastic composites, and more are constantly coming online. This was the message from Dr. Deborah Mielewski, senior technical leader of sustainable and advanced materials at Ford, during her recent “Greener materials for a greener world” virtual keynote at the 2020 SPE Automotive Composites Conference.
According to Mielewski (below), Ford already has more than 10 renewable materials in production, including natural fiber reinforced composites such as wheat straw, rice hulls and tree-based cellulose fiber that exceed traditional-material performance. “Over the past five years, we have kicked off several new material investigations with cellulose nanofibers and materials from carbon dioxide,” Mielewski said, “and we are applying our knowledge in green materials to the exploding area of 3D printing.”
Mielewski initiated the biomaterials program at Ford in 2001, and her team was the first to demonstrate soy-based foam that met all automotive-seating requirements. Ford launched soy-based foam on the 2008 Mustang, and soy seat cushions, backs and headrests have since been employed on every North American-built Ford vehicle. “Bio-based foams currently reduce Ford’s greenhouse gas emissions by over 25 million pounds and reduce petroleum dependence by over 5 million pounds annually,” Mielewski claimed.
Plentiful source material
The Ford biomaterials research team works to expand the use of sustainable plastic materials in vehicles to reduce dependence on petroleum, create new markets for agricultural products and reduce vehicle weight to reduce vehicle emissions. According to Mielewski, there’s a wealth of sources to consider just within the natural fiber realm, which she broke into four categories: traditional natural fibers (kenaf, hemp cellulose); forest residues (wheat, straw); recycled fibers (fillers from carpet, cardboard) and industrial co-products (grape pumice, lignin).
“If you walked into my lab, you would see it looks a bit between a farm and maybe a landfill,” Mielewski related. “We're looking at all of these fibers, all of these possibilities. Almond shells, walnut shells, shrimp shells, lobster shells, because many of them have excellent mechanical properties. This idea that something that comes from plant agricultural waste or from a landfill will have compromised mechanical properties is silly. Many of them have advantages is what we're learning.”
“And while they have these advantages on our vehicle, we can also count on the fact that they're better for the planet because they're available,” she continued. “They're above ground. We burn many of them. Let's not do that anymore. Let's not put them into landfill. Let's use these side products of agriculture, these beautiful materials that are right in front of us to make our cars better.”
Always open for ideas
One of the most heartening things in Mielewski’s work is witnessing unrelated industries find synergies. “When we started, we were coming up with our own ideas on how to do this, but now people are coming to us. I don't think I ever say ‘No,’” Mielewski quipped. “I encourage people to come to us with their ideas. We will give it a whirl even though it sounds crazy just to see what kind of properties we get for that initial screening.”
One of the latest successes is from a coffee byproduct. Late last year Ford partnered with McDonald’s to launch its first coffee-chaff-reinforced-plastic production part, a headlamp housing for the Lincoln Continental. Coffee chaff is the dried skin of the bean that comes off during the roasting process, millions of pounds of which are created by the food & beverage industry each year.
The chaff is converted by heating it to high temperatures under low oxygen and combining it with plastic and other additives. In pellet form, the material can be molded into various shapes. According to Ford, the chaff composite meets quality specifications for parts like headlamp housings and other interior and under hood components. Resulting components are 20% lighter and require up to 25% less energy during the molding process. Heat properties of the chaff component are also significantly better than the previously used material.
According to Mielewski, who specifically credited the work of Amar Mohanty at the University of Guelph, along with Varroc Lighting Systems and Ontario’s Competitive Green Technologies (CGT), the McDonald’s partnership allowed 40% of the talc in the previous material to be replaced with coffee chaff, while also knocking off a half pound of weight per vehicle. “We cannot take credit for everything, we implement,” Mielewski said. “He [Amar] did all the hard work with CGT, working toward making this high-quality bio carbon from McDonald's coffee chaff to meet every one of our requirements. It gives us better heat deflection, better life cycle and weight reduction.”Continue reading »