Cadillac's new CT6, set for release in the fourth quarter of 2015, will be built with various types of advanced and lightweight materials and manufactured using a combination of joining techniques, a first for any GM model. A $300 million investment in the Detroit-Hamtramck Assembly plant led to a new 138,000-ft2 (12,820-m2) body shop that includes 205 robots specifically dedicated to the manufacturing of the luxury sedan.
Among the techniques being used to join the CT6’s dissimilar materials are aluminum spot welding technology; aluminum laser welding, which creates a seamless joining of exterior panels; self-piercing rivets, which are able to join different types of materials together with a clean appearance; flow drill screws, which are able to join different types of materials and are used in conjunction with adhesive; and aluminum arc welding and structural adhesive are also separately used for CT6 body assembly.
Twenty-eight robots weld both the inner and outer vehicle frames on the vehicle body in two separate framing stations, joining the body-in-white together from all angles. The robots are mounted above and beside the vehicle and can also reach beneath it. The two framing processes were choreographed to compensate for different microscopic vibrations.