Carlyle said it will maintain a minority stake in JMC and participation on the board of directors.
According to Carlyle, JMC will put in place a new capital structure and debt facilities to enhance its growth opportunities.
Carlyle managing director Andrew Marino said JMC is a great example of how manufacturing in America can thrive with the right leadership, strategic vision and capital investment.
"Working closely with the Zekelmans and management we have made JMC a stronger company economically and from an environmental and governance standpoint, and we look forward to continuing to create value for JMC in the future," Marino said.
Financial details were not disclosed for the transaction, which is subject to financing and is expected to close by 31 March 2011.
To retire the company’s existing debt and facilitate the transaction, JMC Steel Group will borrow approximately $1.1bn.
