Effects of tempering temperature on tensile and hole expansion properties of a C–Mn steel

Effects of tempering temperature on tensile and hole expansion properties in a dual-phase C–Mn steel were investigated. The ultimate tensile strength and yield strength decreased and elongations increased with an increase of tempering temperature. The hole expansion property increased significantly at the tempering temperature ranging from 200 to 300 °C and did not show significant difference when tempering temperatures were lower than 200 °C or higher than 300 °C. The relationship between the hole expansion property and microstructural evolution has also been discussed.