厚规格钢板蛇形轧制变形渗透性和板形控制机理研究

In order to make the thicker steel plate have fine microstructure and excellent mechanical property, it is crucial to keep the inner regions have enough deformation during thicker steel plate rolling process. The shear stress which can be used to improve the deformation permeability will be produced in the deformation region during asymmetrical rolling. Consequently, the needed reduction rate will be decreased too. The top working roll will move to a distance along rolling direction in order to solve the plate shape problem. So the snake rolling method that can improve the inner deformation and plate shape will be obtained. These factors such as roller speed ration, roller offset and reduction will be considered in order to obtain the law these parameters have brought to deformation permeability and plate shape. The influencing law that the roller speed ratio has brought to inner deformation of thicker steel plate can be obtained by theoretical analysis, simulation and experimental study. The computational mode of deformation permeability during snake rolling process should also be instructed. The influencing law that the roller offset has brought to shape plate after snake rolling process can be obtained by theoretical analysis and experimental study. The setting model of process parameters can be instructed when the plate shape is well after snake rolling. In order to get fine microstructure the increasing billet thickness and reduction ratio methods are often, but it will be restricted by ingot thickness and equipment capacity. The snake rolling can break these restrictions, so it is of vital significant to open up new rolling technology for thick steel plate's production.

厚规格钢板轧制生产的关键在于轧制过程确保钢板中心区域具有充分的变形量，以使心部获得良好组织及力学性能。异步轧制在变形区产生的剪切力有助于变形向钢板中心渗透而降低厚钢板所需压下率。为了解决异步轧制轧后板形问题采用将上工作辊偏移的方法，即将所谓蛇形轧制用于厚钢板轧制生产，以期既能增加钢板心部变形又能改善轧后板形。为此，需要①研究异速比、轧辊偏移量、压下量等工艺因素对厚度方向变形渗透性和板形的影响规律；②结合理论模拟和实验研究量化异速比对厚板心部变形量的影响，建立蛇形轧制工艺条件下的钢板内部变形渗透性模型；③结合理论和实验研究量化上工作辊横移量对厚板异步轧制过程的板形影响，建立蛇形轧制工艺条件下板形良好时的轧制工艺参数设定模型。本研究突破厚规格钢板轧制工艺采用提高坯料厚度、增加压下率等常规方法所受到的铸锭厚度及设备能力限制，对于开辟厚规格钢板新型轧制生产工艺将具有重要意义。

蛇形轧制方法在变形区产生的剪切力有助于变形向钢板中心渗透，增大变形程度，细化心部组织。但是蛇形轧制是一种新型轧制方法，在铝板中的应用刚刚起步，在厚钢板轧制中的研究几乎是空白的，因此本研究采用有限元数值模拟方法与实验分析方法对厚规格或特厚规格钢板蛇形轧制方法进行研究分析。通过模拟分析获得了相关工艺参数对钢板厚度方向变形渗透性和轧后板形的影响规律，建立适合厚钢板蛇形轧制的工艺参数模型，获得了在多道次蛇形轧制过程中各道次板形良好时的工作辊的偏移量。并通过实验分析验证了上述理论分析的正确性。本研究将为蛇形轧制方法的实际应用提供指导作用。