Effects of Pre-Strain and Aging Treatment on the Mechanical Properties of 1.0wt.%Cu Containing Hot Rolled Steel Sheet
The effects of pre-strain and aging treatment on the mechanical properties of hot rolled steel sheet containing 1.0wt.%Cu were investigated. As the amount of pre-strain increased, the maximum hardness increased and the time to reach its peak hardness decreased. Tensile strength of 10% pre-strained steel was 600MPa. This value was about 150MPa higher than that of hot rolled steel. In case of 30% pre-strained steel, the strength was further increased to 657MPa. Such a strength increase was due to the strain hardening and enhanced precipitation reaction of Cu-clusters. TEM study revealed that fine Cu-clusters were uniformly dispersed throughout the grain. This means that the precipitation of Cu-clusters was mainly controlled by the vacancies introduced during the pre-straining process. The size of Cu-clusters was about 10~20nm at peak aged condition and they had spherical shape.
S.-G. Kang and T. Kobayashi
I. G. Kim et al., "Effects of Pre-Strain and Aging Treatment on the Mechanical Properties of 1.0wt.%Cu Containing Hot Rolled Steel Sheet ", Materials Science Forum, Vols. 449-452, pp. 517-520, 2004