Cleveland-Cliffs Corporation marked the fifth anniversary of its acquisition of AK Steel with a news conference where CEO Lourenco Goncalves outlined the company’s ambitious plans for expansion. Goncalves revealed that Cleveland-Cliffs is working on a deal to acquire U.S. Steel, which would make it the largest steel manufacturer in the United States.The acquisition plan involves a partnership with Nucor, which would take over U.S. Steel’s electric furnaces. The plan would keep U.S. Steel headquartered in Pittsburgh.