POSCO has signed a HyREX Collaboration Agreement with BHP, Australia's largest mining company, to begin commercial technology validation of POSCO's proprietary hydrogen-based steelmaking process. Using BHP iron ore, POSCO will assess HyREX's stability under varied raw material conditions, examine performance differences linked to ore characteristics and quality, and determine blending conditions for commercial facilities. HyREX uses hydrogen instead of coal as the reducing agent to produce molten iron without carbon dioxide emissions. The companies will also share raw material technology expertise and jointly explore ways to reduce Scope 3 emissions generated during mining and raw material supply. The agreement follows a memorandum of understanding signed last October in the presence of Australian Prime Minister Anthony Albanese and POSCO Group Chairman Chang In-hwa. It also expands POSCO's HyREX commercialization network beyond its 2024 technology cooperation agreement with Primetals to include BHP as a raw material supplier. POSCO said the collaboration supports its phased commercialization roadmap and broader open-collaboration strategy, while BHP said it would help advance low-carbon steelmaking pathways that can use Australian iron ore.