Study on the influence of non-uniform temperature on the deformation state of DP590 steel during rough rolling

Focusing on DP590 steel, this study employs numerical simulation to investigate the formation mechanism of temperature field inhomogeneity during continuous casting and its impact on multi-pass rough rolling. A 2D continuous casting temperature field model developed in Abaqus, defined with modeling parameters including a slab size of 1600 × 230 mm, a casting speed of 1.1 m min −1 , and specific water volume 1.99 l kg −1 , reveals the thermal evolution during the cooling process. A 3D heating-rolling model incorporating defined parameters of work roll radius 500 mm, speed 6 rad s −1 further analyzes how temperature inhomogeneity affects rolling force and stress–strain distribution. The results demonstrate that the non-uniform temperature field significantly exacerbates rolling force fluctuations, with the rolling force under 600 s of heating increasing by approximately 15%–20% compared to a uniform 1200 °C temperature field, while simultaneously inducing a stress gradient along the thickness direction (stress difference exceeding 20 MPa between surface and core) and non-uniform strain distribution (strain difference reaching 0.68); however, extending the heating duration to 1200s reduces the core-surface temperature difference to below 300 °C, achieving stress–strain distribution uniformity comparable to isothermal conditions. Optimized heating processes enhance deformation uniformity, resolving the conflict between low-energy production and product quality in low-speed casting scenarios.