ＵＡＣＪ、テスラ車向けにアルミ部品増産 米で30億円投資 (Japanese article - use google translate) UACJ is going to increase alminum parts production for Model 3. # UACJ is Furukawa and Sumitomo JV for alminum UACJ invests 3 billion Yen ($30M) into their Michigan Plant subsidiary and increase its production for 50% by December. They are going to produce "Model 3 roof rails and supportive parts for frames". This plant already makes alminum frames for Tesla and Ford, and this increased production will be used for Tesla and other car manufacturers as well. ----- so the news didn't say the frame is made of alminum.