Lightweighting – Tesla’s goal is to accelerate the world’s transition to sustainable energy. “Transport is one of the few places where non-sustainable energy has been hard to displace,” said Kuehmann. “We can use sustainable energy in our homes and in our businesses. But it’s been very difficult to allow sustainable energy to take over transport systems.” Tesla is taking on commercial transport with its Tesla Semi, which has a number of prototypes under development. “Even though it’s a big truck, weight is really the big driver,” said Kuehmann. “Every kilogram of weight we have in the vehicle or in the battery pack, takes a kilogram out of the potential payload capacity.” Tesla is looking at advanced technologies, including sheet molded products and other composites, to reduce weight in the body structure, the enclosures and the battery systems.
Design Engineering – The Tesla Model 3 utilizes aluminum, mild steel, high strength steel, ultra-high strength steel and composites. “Not only is this about getting the right materials where we need them, but this kind of approach [requires] looking at the joining technologies,” said Kuehmann. “When I talk with the design teams when we start these projects, I say, ‘Let’s start at the joints, and we’ll design the car out from there.’ That’s how much emphasis you have to put on the joining technologies.” The team uses both advanced castings and advanced composites to integrate more of the body structure into fewer parts with fewer interfaces.
“We are taking an approach at both [Tesla and SpaceX] that really makes materials engineering part of the overall design and engineering function,” said Kuehmann. They do that with a technique called integrated computational materials engineering (ICME), where they design a part and material together using process simulation software along with material modeling capabilities to create the whole system. “That’s where the power comes from,” said Kuehmann.
Collaboration – The projects at SpaceX and Tesla all have one thing in common: They require teamwork. “One of the benefits of working in both groups is that we can utilize people across those teams,” said Kuehmann. “We do collaborate regularly.”