Mo addition of high-strength seismic rebars subjected to Tempcore processes for tensile strength enhancement

Abstract

High-strength seismic reinforcing bars (rebars) reduce seismic damages by achieving low yield ratios. The effect of adding Mo to high-strength Tempcore rebars for achieving low yield ratios was investigated. The continuous cooling transformation diagram shifted with Mo addition to achieve higher hardenability, thereby producing a low-temperature transformed phase, inside the rebar. The work-hardening exponent increased with increasing Mo content, which was due to the fine grain size of the low-temperature transformed phase and its high dislocation density. The addition of 0.11 wt% Mo provided a feasible solute drag effect for constructional steels and achieved high strength and excellent seismic resistance.

Keywords

• Tempcore
• Yield ratio
• Mo-alloyed rebar
• Continuous cooling transformation
• Bainitic microstructure
• Precipitation