Tesla casts a new strategy for lightweight structures

The EV maker boldly invests in the world's largest aluminum die-casting machine to manufacture entire rear underbody structures.

Aluminum is synonymous with “weight-saving” in most contemporary automotive-engineering reference points. But apart from a few applications - most notably Ford's F-Series pickups - aluminum largely is deployed where steel can be readily displaced without performance loss or for comparatively small components that deliver comparatively small weight or process savings.

Electric-vehicle maker Tesla is readying the next step in aluminum use, however - one that effectively matches Ford's “big gain” approach by specifying a massive piece of structural die-cast aluminum for the rear underbody of the recently launched Model Y crossover. According to Tesla CEO Elon Musk, this new aluminum application represents a radical step for its design and manufacturing advantages and its light-weighting potential. Musk is renowned for outsized promises, but in the case of the Model Y's die-cast rear underbody, his enthusiasm for this advanced use of aluminum - cast by a house-sized “giga press” - is supported by manufacturing experts who call it a game-changer.