In 1852, it became part of the Rimamurányvölgyi Vasmű Egyesület, later evolving into the Rimamurány-Salgótarjáni Vasmű Rt., a major player in Hungary´s iron industry. Following nationalisation in 1946, the facility was renamed Ózdi Kohászati Üzemek (ÓKÜ) in 1950.

At its peak, ÓKÜ employed over 20,000 workers and was central to the city´s development, providing housing, healthcare, and cultural amenities. However, by 1992, due to economic challenges and loss of markets, steel production ceased, leading to the company´s dissolution. In 1995, the Ózdi Acélárugyár Kft. was restructured into Ózdi Acélművek Kft., which was acquired by Germany´s Max Aicher GmbH & Co. in 1997.

The bar rolling mill was set up during the 70ˇs to expand the production of the old plant, while the electric steel mill with one 70t EAF was constructed in 2000.

Today, ÓAM Ózdi Acélművek operates as a modern steel manufacturer, continuing Ózd´s industrial legacy.