October 16, 2020 High-Strength Metals And Polymers in the Auto Industry

A look at how high-strength metals and polymers are changing the face of the automotive industry.

The Audi A8 multi-material vehicle is the perfect example of where the automotive industry is heading in terms of new metals boasting greater strength, lighter weight and improved malleability. This vehicle’s body boasts a blend of aluminum, steel, magnesium alloys, and carbon fiber reinforced polymer (CFRP). In fact, the driver and passenger area, or cell, is made of CFRP. As stated by Matmatch, many people are surprised to discover that “the strongest material human beings have ever created comes not from metal, but from carbon, the same material that makes up the tip of a pencil.” Of course, considerable work is put into transforming carbon into an immensely powerful material with unique properties that hold great promise for the vehicle industry.

The Audi A8 A Compendium Of Materials

The breakup of the A8 indicates the extent to which a multi-material focus can be used to achieve specific aims. Around 58% of the structure is made of aluminum, the front strut tower comprises magnesium (which lends the vehicle less weight but greater rigidity), and the passenger cage adds a 33% CFRP quotient, once again for greater rigidity). Of course, CFRP has come to be the veritable ‘mark’ of luxury cars, since they are costly and involve complex processes. To start off with, their use in vehicles begins with the arrangement of sheets of fibers coated with resin and adhesive into a mold. Individual fibers are woven together, and the new structure is placed in a high-temperature, high-pressure oven. The result is an ultra-light material with an atomic weight of less than 50% of aluminum.

CFRP And Safety

Purchasers who put safety first will often compare safety features of different vans, cars, and trucks, looking into how well the vehicle handles slippery roads, brake performance, and of course, performance in crash safety tests. Indeed, drivers surveyed greatly value the extent to which their vehicle would protect them in an accident. The average driver in the U.S. logs 13,476 miles per year, and each added mile increases the likelihood of a potentially life-changing road event. Vehicles made with CFRP fare well in the realm of safety for many reasons. Firstly, some carbon fibers can possess up to 10 times the strength of steel. Secondly, the inherent stiffness of CFRP means that when a vehicle takes a corner, the body flexes less than it would if it were made of aluminum or steel, thus lending greater traction to the wheel.

New Materials Married To 3D Printing

In addition to blending different metals and polymers in new ways, manufacturers are also using 3D technology to meet high safety standards and exceed customer performance expectations. The company Divergent3D, for instance, is building its car chassis with 3D printed metal nodes that connect to carbon fiber-reinforced plastic structural rods. The main body of the car, meanwhile, is made of plastic composite, but the manufacturers are already making it clear that they are open to using other materials. “The body is not structural and could be made from anything,” they say. Local Motors is another company that is combining 3D technology with carbon fiber-reinforced plastics for greater strength. Larger companies like Ford have also already announced their interest in 3D printing tech as a way to create vehicles made of both traditional and nouvelle materials.

Smart Materials

The next generation of materials in the automotive industry are undoubtedly ‘smart materials’ – those which react and change when they are espoused to heat and light, chemical reactions, electrical power, and more. Car manufacturers are already looking into the possibility of using shape memory materials, which take on a new shape at low temperatures then return to their original form at higher temperatures. The interior of automobiles are a particular interesting setting for this type of material. Imagine a car seat made of shape memory alloys that adapt to the driver’s contours with the need to use manual adjustment or biometrically automated devices.

It’s an exciting time indeed for car manufacturers wishing to blend materials according to their needs. From smart materials that ‘mold’ to the driver’s shape, to sturdy CFRP cells that keep drivers and passengers safe, there are many ways to personalize cars and make them safer and even more pleasurable to drive. Finally, tech such as 3D printing is adding fast, lightweight, sturdy components into the equation, widening the gamut of possible materials that can be printed into the car of a designer’s dreams. And if you thought that traditional materials were all but lost, think again. Ford is currently experimenting with sustainable materials – including soy, wheat straw and bamboo.

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