Continuous bending and straightening technology of Q345c slab based on high-temperature creep deformation

Abstract

A new continuous bending and straightening casting curve with the aim of full using of high-temperature creep deformation was proposed. The curvature of bending and straightening segment varies as sine law with arc length. The basic arc segment is shortened significantly so that the length of bending and straightening area can be extended and the time of creep behavior can be increased. The distance from solidifying front in the slab was calculated at 1200 °C by finite element method. The maximum strain rate of new casting curve at different locations inside the slab is 6.39 × 10⁻⁵ s⁻¹ during the bending segment and it tends to be 3.70 × 10⁻⁵ s⁻¹ in the straightening segment. The minimum creep strain rate is 7.45 × 10⁻⁵ s⁻¹ when the stress is 14 MPa at 1200 °C. The strain rate of new casting machine can be less than the minimum creep strain rate. Thus, there is only creep deformation and no plastic deformation in the bending and straightening process of steel continuous casting. Deformation of slabs depending on creep behavior only comes true. It is helpful for the design of the new casting machine and improvement of old casting machine depending on high temperature creep property.