The teams are so interlinked that Tesla recruiters referred to them as a "SpaceX/Tesla Materials Engineering organization. Two years ago, Musk hired Apple's alloy expert Charles Kuehmann to lead materials engineering at both of his companies simultaneously.
* SpaceX transferred friction stir welding equipment to Tesla.
* they are also sharing knowledge of materials engineering to create new alloys for their respective products.
* With the Model 3, Tesla used less aluminum and more steel.
* Tesla and SpaceX also both use the space-grade superalloy Inconel.
* set up its own glass team within its materials engineering effort. They developed new glass products for Tesla's solar roof tiles, the Tesla Semi, and in the Tesla Model 3.