This course provides a comprehensive exploration of microalloyed forging steels, focusing on their properties, processing methods, and industrial applications. It examines the limitations of conventional direct hardening steels and introduces microalloyed steels as cost-effective and high-performance alternatives. Learners will analyse material selection criteria, including mechanical performance, lifecycle cost, and sustainability considerations. The course details the production processes of alloy steel forgings, highlighting cost distribution and optimisation strategies. It explores the influence of forging parameters—such as temperature and cooling rate—on microstructure development and mechanical properties through precipitation strengthening mechanisms. Additionally, the course evaluates the performance of air-cooled and air-hardened microalloyed steels compared to quenched and tempered steels, with a focus on strength, toughness, fatigue behaviour, and machinability. Real-world applications, particularly in automotive components such as crankshafts and wheel hubs, are examined to demonstrate practical implementation. Emerging developments, including grain refinement techniques and advanced manufacturing processes like fracture splitting, are also introduced.