Apple's Duo Foldable Gets a 3D-Printed Hinge Cover

The First Apple Foldable Has a 3D-Printed Secret

Apple's new CEO John Ternus led his first major product event last week. The headline was the iPhone Duo, the company's first foldable. Tucked inside the hinge is a part made with additive manufacturing.

The Duo's hinge cover uses an AI-driven 3D printing process that deposits micro-layers of a special photopolymer onto a recycled titanium hinge. Apple has not confirmed the exact process, but the description closely matches work previously done by Chinese 3D printing firm BLT for the OPPO Find N6. BLT has been part of Apple's supply chain, so the technology may have come directly from that partnership.

Ternus replaced Tim Cook as CEO earlier this year. He spent decades in Apple's hardware division and was most recently senior VP of hardware engineering. His appointment signals how serious Apple is about controlling its physical product roadmap.

The Duo hinge is not just a novelty. It solves a real problem: foldable phones need a hinge that stays smooth over thousands of folds while protecting the screen. 3D printing lets Apple produce complex geometry that would be hard to achieve with traditional tooling. The recycled titanium hinge also fits with Apple's stated carbon-neutral goals.

Apple has been investing quietly in US manufacturing capacity for several years. The company opened a new advanced manufacturing center last year and has continued to fund small and medium enterprises that support metal additive processes. The Duo hinge is the most visible proof yet that those investments are turning into actual products.