带钢高温态横向瓢曲的理论与试验

对连续退火生产线上处于高温态的薄宽带钢的横向瓢曲的生成机理提出一种新的解释，认为传统认知的横向瓢曲是横向温差造成的所谓“热瓢曲”的论断并不正确，带钢横向瓢曲的主因是由于带钢宽向中部局部区域张力集中导致不均匀拉伸变形造成的局部屈曲，即类同于冲压成形中的起皱皱曲变形，并通过解析分析和数值计算研究揭示出带钢横向瓢曲变形过程的力学规律；借鉴YBT试验方法，以冷态下的板料不均匀拉伸试验验证了解析分析方法和数值计算模型的正确性；研究提出了抑制连续退火炉内带钢“热瓢曲”现象的一系列对策措施，用于宝钢股份2#连退机组取得成功。

Theory and Experiment of the Strip Transverse Buckling under High Temperature

A brand-new explanation about the transverse buckling mechanism of strip in high temperature state on the continuous annealing production line (CAPL) is put forward—the traditional viewpoint that the transverse difference of temperature results in the buckling is incorrect, the main reason for the strip buckling is that the local tension converges toward the central width of strip results in the non-uniform tensile deformation, this resembles the wrinkling deformation in press forming. At the same time, the mechanics laws in the process of buckling are revealed by the analytical and finite element method. By using YBT test method for reference, the correctness of the analytical method and numerical calculation model is validated by uneven tensile test of sheet metal in cold state. The research brings forward a series of countermeasures to restrain the “heat buckling” of strip in the annealing furnace, and the application of which in the 2# CAPL of Bao Steel has achieved full success.