We have developed a micro-macro coupling model for simulating rolling load, rolling temperature and microstructure evolution in tandem wire rod rolling. Because temperature analysis was performed by finite difference method, deformation analysis by rectangular conversion and microstructure analysis by incremental formulation for recrystalization and transformation, it was possible to predict rolling load, rolling temperature and microstructure with good accuracy. Next, thermomechanical rolling was applied to the actual wire rod rolling of plain carbon steel, which was reheated at a low temperature, cooled using cooling troughs, continuously rolled in Ar3 and cooled using an interstand cooler in finishing mills. As fine as-rolled microstructures, particularly near the surface of the wire rod, not only wire rods but also cold heading and cold form rolling bolts had a high fatigue limit.
