The lightweighting recipe also can be more exotic with

low-volume “super cars.” Honda Motor Co. this year began producing its new

Acura NSX at Marysville, OH. The car, with a $156,000 starting price, has an aluminum body, the same as its predecessor, which Honda discontinued in the 2000s. The previous NSX was made in Japan. Another new super car, Ford’s GT, features a carbon

fi ber body, a material used in some race cars. In other cases, the recipe calls for more of a mix. GM’s Cadillac CT6 has a mix of aluminum, including the

exterior, and diff erent types of high-strength steel, includ- ing the sedan’s safety cage. The luxury four-door also is the lead application for a GM-developed steel-to-aluminum spot welding process. The company has 19 patents on the hardware and controls.

ture in the liftgate, to cut 113 kg from the minivan, including 76 kg from its body. “In a general sense, the strategy we’ve been pursuing is

to predominantly stay with steel for body structures and use alterative materials in closure panels,” said Jeff Tibben- ham, who supervises body in white engineers at FCA. FCA also uses computer models. “We take those

models,” Tibbenham said. “We substitute diff erent materi- als for the diff erent applications. We make thousands of computational runs. It’s a very upfront and early devel- opment process. Slowly, we arrive at what is the most optimal solution.” The Pacifi ca was one of the fi rst models developed this

way, he said. “This is the footprint for our development going forward.” In the end, the Pacifi ca included aluminum engine brackets and rear upper shock mounts and a high- strength steel front suspension cradle. Automakers also are fi nding ways to reduce the number of parts. With the Cadillac CT6, the auto- maker employed high-pressure die castings to im- prove stiff ness. That enabled GM “to remove 190 or so parts because we could do it in a single casting,” GM’s Klein said.

Suppliers respond Lightweighting is a big priority for suppliers,

who are fi nding themselves coordinating earlier with vehicle makers. At FCA, representatives of two steel suppliers are “really in house with us,” Tibbenham said. “They

A body in white for the multi-material Chrysler Pacifi ca minivan.

Among the technical challenges: There is a 900°C dif-

ference in the melting point between aluminum and steel. Previously, steel would be spot-welded to steel or alu-

minum to aluminum. Steel would then be riveted to alumi- num. GM said the new process eliminates the riveting step and can be used with the same welding equipment. GM’s Klein said computer-aided engineering is a major part of the automaker’s lightweighting eff orts. “It gives us the chance to assess diff erent solutions,” Klein said. “It allows us to go through so many iterations.” Computer simulations enable engineers to determine how lightweighting steps aff ect a vehicle’s performance, he said. FCA US LLC’s new Pacifi ca used high-strength steel as well as other materials, including a magnesium inner struc-


come to us with new materials and say, ‘What if?’ Our job is to package and engineer vehicles. Having their engineers, they interact daily with my engineers.

That’s been a great asset to use.” Tibbenham declined to identify the steel companies

involved. Gestamp (Madrid), a maker of metal automotive

components, co-developed a rear rail system made from high-strength steel with Honda, for the Civic. Energy from a crash is absorbed by system components. “You have to do the design much earlier,” said Paul

Belanger, Gestamp’s director of research and development for body in white. “We have to be joined at the hip for this to be successful. We were in there one, two years before the typical time we would have been sourced.” The system, which includes “soft zones,” folds “in a snake fashion” in a collision, he said.

Fall 2016

Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68