Research on the Strength and Toughness Mechanism of High‐Strength 0Cu6Ni2.7Mn Steel Based on Thermo‐Mechanical Control Processing and Heat Treatment

With the advancement of high‐strength steel technology, Cu‐bearing steel is increasingly being utilized in industries such as shipbuilding. Cu addition enhances the strength, hardness, and corrosion resistance of steel. However, excessive Cu can lead to segregation, thereby degrading the material's performance. To fully leverage the precipitation strengthening effect of Cu while avoiding segregation, this study designed a high‐strength steel with 6% Cu content. Through thermo‐mechanical control processing and appropriate heat treatment, the optimal partition coefficient of Cu is achieved. In the 0Cu6Ni2.7Mn steel samples, no segregation of Cu is observed. After solid solution treatment at 900 °C for 1 h followed by aging at 540 °C for 2 h, the best balance in mechanical properties is achieved, with the yield strength reaching 920 MPa and impact work exceeding 400 J. By controlling the distribution of dissolved Cu and precipitated Cu phases, the synergistic effects of Cu solution strengthening and precipitation strengthening are utilized to achieve high toughness in ultrahigh strength steel, providing a significant reference for the future development of high‐Cu steel materials.