Page 46 - MetalForming Magazine February 2023 - Metal Forming for the Automotive Industry

THE SCALING UP OF AUTOMOTIVE ALUMINUM
such as the Ford F150 or some JLR models,” White continues, “we see only 20 to 30 gauge/grade combinations, and we don’t need additional protec- tive coatings because aluminum self- heals. This lack of complexity is music to the ears of many OEM manufactur- ing engineers.”
In another study, Alumobility has investigated developing an aluminum B pillar, “testing our premise using a popular mass-produced electric vehicle (EV),” shares Greco. “We developed a high-strength 6XXX-series aluminum pillar to test side-by-side with the cur- rent steel solution.”
In both studies, significant weight savings were realized while meeting or exceeding performance attributes for various load cases and reducing the total number of component parts and joints.
“The goal, then,” shares Greco, “is to drive more in-depth conversation between the aluminum sheet produc- ers and engineers working in the auto- motive industry, to help engineers understand what they can expect in terms of performance, value and manufacturing integration, for less complexity and more sustainable solutions.”
The Virtuous Weight Spiral
One area of focus, White shares, relates to what he calls the “virtuous weight spiral.” He explains:
“With aluminum, if we can take enough weight out of the BIW and chassis we can downsize the power- train, a huge benefit with EVs, and per- haps then can even reduce the number of battery modules required—and bat- teries are more expensive than alu- minum. The virtuous weight spiral, therefore, occurs when we save enough weight to downsize the power train, including the battery size on an EV, and use the money saved to pay for any material cost difference for the aluminum.”
This approach enables a lighter overall vehicle with less batteries and more energy efficiency, as demonstrat-
Alumobility recently published the results of a study demonstrating the weight savings in a vehicle top-hat structure (upper body structures including the roof and bodyside outer panels.
The aluminum top hat developed by Alumobility comprises 5000-series aluminum—rela- tively low strength but fairly ductile and useful for auto-body closures; 6000-series— bake hardened and used for outer, exposed panels; and 7000-series—“Where we approach the limits for cold forming,” says Alumobility technical director Mark White, “and start to look at hot forming.”
www.metalformingmagazine.com
MetalForming/February 2023 43
ed by another recent Alumobility proj- ect, the Last Mile Delivery Van study, where overall cost of ownership was reduced while payload was increased.
When it comes to stemming con- cerns with the ability to form and join aluminum in automotive structures, the goal of Alumobility through its var- ious studies is to dispel the “urban myths,” says White. “I look at forming of high-strength aluminum sheet the same as I would approach forming high-strength steel parts, dual-phase AHSS grades for example—we see pret- ty much the same springback, the same thinning and the same elongation as
a DP500 steel, for example,” he says. “So, stamping a 6000-series aluminum structural part is similar to stamping a DP500 part, with a similar set of form- ing challenges. And, there are some great software tools—design and sim- ulation—available to help die designers and metal formers identify what they can and can’t do, so we look to demon- strate this in our projects.”
When automotive engineers talk aluminum, specific grades dominate the conversation:
• 5000 series—Relatively low strength, says White, but fairly ductile and useful for auto-body closures.