Effects of Pre-Strain and Aging Treatment on the Mechanical Properties of 1.0wt.%Cu Containing Hot Rolled Steel Sheet

Abstract:

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.

• Periodical: Materials Science Forum (Volumes 449-452)
• Pages: 517-520
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.449-452.517
• Online since: March 2004
• Authors: In Gon Kim, Yang Do Kim, In Bae Kim
• Keywords: Aging Treatment, Cu Containing Steel, Hot Rolled Steel Sheet, Post Heat Treatment, Precipitation of Cu-Cluster, Pre-Strain, Tensile Strength

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