Russian aluminum giant United Co. Rusal plans to invest $200 million in a Kentucky rolling mill that would be the largest new aluminum plant built in the U.S. in nearly four decades.

The plant, which startup Braidy Industries Inc. plans to open next year in Ashland, Ky., is the largest project being pursued in the domestic aluminum industry under the Trump administration’s 10% duty on imports of the metal, imposed a year ago. It would also draw more imports into the U.S. because the mill would roll aluminum slabs from abroad into thin sheets for the auto industry.

Braidy’s ability to attract one of the world’s largest metal companies to the $1.7 billion project reflects the changing state of the rolled aluminum market. After decades of stagnant sales of aluminum sheet for cans and other staple products, rolling companies in the U.S. are pivoting to production of higher-profit sheet for vehicle bodies. Car makers increasingly are replacing steel with aluminum because it is lighter. Now tariffs have pushed up the cost of foreign-made aluminum, giving domestic producers greater pricing power in a market where production capacity is already tight.

“It’s the start of a megatrend and I want to be in the middle of it,” said Braidy Chief Executive Craig Bouchard. Rusal is the world’s second-largest producer of raw aluminum. Braidy said Rusal would supply the new mill with as much as 200,000 metric tons of foreign-made aluminum each year, most of it from an aluminum smelter under construction in Siberia.

An expanded version of this report appears on WSJ.com.

Also popular on WSJ.com:

Washington waits in suspense for Mueller report.

Baby boomers and the art of parenting adult kids.

Want news about Europe delivered to your inbox? Subscribe to MarketWatch’s free Europe Daily newsletter. Sign up here.