Nucor Corp.'s board of directors named John Walker as nonexecutive chairman.

The board also elected Nucor President and COO Leon Topalian as a director. Both appointments are effective Jan. 1, 2020.

Walker has been an independent director of Nucor since 2008. He served as nonexecutive chairman of Global Brass and Copper Holdings Inc. from March 2014 to July 2019.

Topalian will step in as Nucor CEO in early 2020.