Apple is adding a U.S. titanium supplier for its new iPhone Duo and expanding domestic production of camera components for the iPhone 18 Pro as part of a push to expand manufacturing in its home country.

The company said Tuesday it will commit up to $100 million over the next three years to Perryman Company, based in Houston, Pennsylvania, for the production of titanium used in Apple products, including the $1,999 foldable Duo.

Since the start of President Donald Trump's second term, Apple has been vocal about its efforts to invest more in the U.S., even as the final assembly of most iPhones remains overseas. In August of last year, Apple launched the American Manufacturing Program (AMP), increasing its plan for domestic spending by $100 billion to a total of $600 billion. Tim Cook, Apple's CEO until last month, appeared at the White House for that announcement, as Trump was pushing the iPhone maker and other tech giants to bolster production in the U.S.

The latest announcement comes as Apple faces severe supply constraints for its first foldable phone, which goes on sale in stores Friday.

Online delivery estimates for some Duo models stretched to roughly 14 weeks on the first day of preorders, according to Morgan Stanley, the longest wait the firm has recorded for a new iPhone in a decade. Apple said Friday that preorder demand had been "nothing short of extraordinary," but hasn't said whether it plans to increase production.

JPMorgan analysts estimate Apple will ship roughly 8 million to 9 million Duo devices this year, below earlier expectations of about 10 million, because of supply constraints. Apple didn't say whether the agreement with Perryman would increase near-term capacity.

Perryman will melt, forge, and roll grade 5 titanium, which Apple said will contain at least 80% recycled material. Titanium is used for the Duo's enclosure, providing durability, according to Apple.

In addition to the Perryman announcement, Apple said Tuesday that it's expanding its partnership with Delaware-based Qnity Electronics, which will manufacture advanced films used in the variable-aperture camera system on the iPhone 18 Pro. The feature allows the phone's main camera to adjust how much light enters the lens depending on conditions, giving users greater control over light and depth.

Apple said nearly 100 components used in the iPhone Duo and iPhone 18 Pro are produced by American companies across more than a dozen states.

"We're thrilled to expand our work with companies producing advanced materials and components for our newest iPhone lineup right here in America," Sabih Khan, Apple's operating chief, said in a statement.

Apple also highlighted investments with other AMP partners, including Broadcom for U.S.-made chips, Corning for specialty glass used in iPhones and Apple Watches, and Amkor, which is constructing a semiconductor packaging and testing facility in Peoria, Arizona.

For the Duo, questions remain about whether Apple can produce enough phones to meet demand for a phone facing unusually long wait times before hitting stores.

—CNBC's Kif Leswing contributed to this report

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