连铸凝固坯壳厚度电涡流在线检测方法研究

项目名称： 连铸凝固坯壳厚度电涡流在线检测方法研究

项目编号： No.61463041

项目类型： 地区科学基金项目

立项/批准年度： 2015

项目学科： 自动化技术、计算机技术

项目作者： 王志春

作者单位： 内蒙古科技大学

项目金额： 46万元

中文摘要： 铸坯凝固坯壳厚度是连铸生产中一个重要参数，它反映了连铸工艺的合理性，并为二冷制度的优化设计提供重要依据。目前国内大量研究集中在通过温度场数值计算推算坯壳厚度。研究能够实现坯壳厚度在线无损检测的方法仍然是急需解决的问题。本项目利用金属凝固点及居里点处电磁特性的突变，研究多层导电结构厚度测量电磁场理论及其应用于凝固坯壳厚度测量的方法；根据铸坯内部温度分布及金属温度和电磁特性的关系，利用电磁场仿真软件建立坯内磁导率、电导率分布，推导多层导电结构中电磁参数非线性连续变化情况下的涡流传感器阻抗表达式并给出有限元数值解，基于仿真正问题数据及粒子群等寻优算法与迭代算法相结合、支持向量机回归、基于记忆的分类方法等先进建模方法获得传感器激励频率、阻抗特征与坯壳厚度的关系，实验验证该模型并进行传感优化设计。为研究工艺参数提供有效检测手段。

中文关键词： 涡流检测；连铸；凝固坯壳；厚度

英文摘要： Solidified shell thichness of continuous casting slab is an important parameter.It reflects the the rationality of continuous casting process， and it can give an important basis for optimization design of secondary coolingschedule. Currently domestic researches centre upon the indirect method which can work out the solidified shell thickness by the calculations of temperature fields . The method which can realize the shell thickness online non-destructive testing is still a problem needed to resolve. When phase transition from solid to liquid state there is sudden change in the magnetic conductivity and electrical conductivity in metal solidification process. This can be useed to research the electromagnetic field theory about thickness measurement of multilayered conductive structures and its application in the solidified shell thickness of continuous casting slab. The main contents are summarized as follows: According to the temperature distribution inside the slab , relationship between metal temperature and its magnetic properties, building the distribution model of magnetic conductivity and electrical conductivity in continuous casting slab by electromagnetic field simulation software .Building the electromagnetic field model of eddy current testing system and the deducing mathematical representation of output impedance by the electromagnetic parameters are highly nonlinea variation, its numerical solution will be given. Building the electromagnetic field model of eddy current testing system and the relationship between sensor's frequency of the excitation, output impedance and solidified shell thickness by the simulation datas and advanced modeling method such as particle swarm optimization, iterative algorithm,support vector machine regression,memory based classification algorithm etc.Doing optimizing design of sensor and validating the model by nail-shooting technique, it can provide an effective online detection means for the study of technological parameters. .

英文关键词： Eddy current testing;Continuous casting;Solidified shell;Thickness