Study on effect of residual stress distributions on kinetics of static strain aging after cold rolling

Abstract

In the present research, the effect of residual stress distribution on the static strain aging (SSA) phenomenon in cold rolled steel was investigated. A three-dimensional model was employed to evaluate the residual stress distributions within the rolled strips, and hole drilling experiments were also performed to verify the data obtained from the mathematical model. Hardness and tensile tests were then performed on the cold rolled samples at different temperatures and aging periods, and the results of these tests were utilised to assess SSA behaviour after different rolling programs. The results show that SSA occurs within the cold rolled steel in the employed aging period, and its kinetics is affected by residual hydrostatic stresses. Additionally, the variation in residual hydrostatic stress distribution due to deformation path, e.g. single- and two-pass rolling layouts, slightly affects the activation energy of SSA and changes the kinetics of SSA after cold rolling.

Keywords:

• Cold rolling
• Static strain aging
• Residual stress distribution
• Mathematical model