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Description
This study investigates a lightweight steel with enhanced elastic modulus via borides reinforced particles. The microstructure consists of an austenitic matrix containing δ-ferrite and 13% TiB₂ particles. The steel exhibits a yield strength of 430 MPa, tensile strength of 630 MPa, elongation of 13.5%, elastic modulus of 225 GPa, and density of 6.98 g cm⁻³. The heterogeneous as-hot-rolled microstructure—equiaxed austenite with elongated δ-ferrite bands and micron-sized TiB₂—enables a favorable combination of physical and mechanical properties. The improved strength-ductility balance is attributed to δ-ferrite’s dual role: high dislocation density provides strengthening through a composite effect, while the soft/hard phase contrast with austenite promotes strain hardening via geometrically necessary dislocations. This work offers a cost-effective route for large-scale production of low-density steels with high stiffness, strength, and ductility.