Page 36 - MetalForming February 2022 Special Automotive Issue

Betting on BEVs
grades, ranging from ultra-low carbon steels to AHSS and the latest 3rd-Gen steels. The online format enables timely updates to keep pace with the devel- opment of new technology and grades.
Hot Stamping Key Player in BEV Production
Hot stamping has evolved as a prime process to shape tough materials for use in BEV applications, so a closer look at this process segment is in order.
“Globally, we are seeing a general trend of automotive OEMs increasing their outsourcing of body and chassis components for BEVs,” explains Paul Belanger, R&D director North America for Gestamp. “In the United States, we see a bit of this trend, but also a signif- icant increase in the overall BEV busi- ness. More electrified platforms are coming onto the scene as well as higher annual vehicle volumes. The number of new automotive OEMs, such as Riv- ian, Canoo, Lordstown and Lucid, also provides an increase in body- and chas- sis-component opportunities.”
BEVs require changes in body archi- tecture to handle energy-absorption demands brought on by the weight of heavy batteries in the vehicle floor.
“This proves especially demanding in the bodyside structure,” says Belanger, “where side-impact events must be managed.”
How does this affect metal formers?
“This opens up a new field of what we call ‘extreme-size’ parts,” Belanger explains. “These large, one-piece hot stampings integrate several compo- nents. A good example: the bodyside reinforcement structure, or door ring, where the individual A and B pillars, sills, roof rails and hinge pillars all can be combined. Here, different material thicknesses and strengths assemble into one overlap patch blank. These blanks are first spot weld- ed and then hot stamped into a single piece all at once. Extreme-size parts offer higher quality standards and tol- erances at a lower cost and lower weight. These parts also feature lower assembly costs due to fewer parts to build into a vehicle.”
Gestamp reports expanding this approach into other areas of the body structure such as floors, rear rail sys- tems and battery-ring structures— nearly all of the body structure.
“We believe this to be a significant step in electrification,” offers Belanger, “while protecting the battery in various crash events—a key requirement for BEVs.”
What challenges does Belanger see in supplying BEV parts, be it material availability, knowledge on forming unique materials or designing parts and processes?
“Material forming and joining tech- nologies for the BEV battery boxes appear to be quite dynamic,” he says. “Many first-generation battery boxes have included massive use of aluminum extrusions, with internal aluminum structures to protect the battery cells. These boxes, often referred to as ‘cells- to-modules,’ include multiple joining technologies such as laser and hybrid welding, friction stir welding and gas- metal-arc welding. Due to the thermal distortion with these types of joining techniques, machining of critical sur- faces is required to bring the parts into acceptable tolerance. The latest trends we see show that the responsibility to protect the battery cells is transitioning from the battery box to the body-in- white. These new-generation boxes, often referred to as ‘cells-to-pack’ or
even ‘cells-to-body,’ are becoming less structural, simpler and significantly less costly. As a result, we see battery trays transitioning back to steel, formed with conventional methods.”
Overall, Belanger concludes, “the growth in BEVs provides significant opportunities to incorporate innovative forming processes coupled with novel product designs to develop cost-effec- tive, lightweight safety solutions. Con- cepts such as extreme-size hot- stamped parts offer body complexity and cost reduction while improving vehicle safety. The rate of change in the automotive industry, driven by the transition to BEVs, will be an interesting and exciting journey.”
Is Your Production Line Up to Snuff?
While automotive-parts suppliers currently contribute 50 to 55 percent of the value of a vehicle powered by an internal-combustion engine (ICE), that might shrink to 35 to 40 percent for a BEV, according to a PwC report. This means greater competition for contracts. To best position themselves to take advantage of the BEV trend and the expected increase in unique form- ing of unique materials, part producers must ensure the flexibility and pro- ductivity of press-line equipment, including coil handlers, presses, trans- fer systems and conveyors.
34 MetalForming/February 2022
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“More electrified platforms are coming onto the scene as well as higher annual vehicle volumes. The number of new automotive OEMs such as Rivian, Canoo, Lordstown, Lucid, etc., also provides an increase in body- and chassis-component
opportunities.”
—Paul Belanger, R&D director North America, Gestamp