摘要
针对极薄镀锡基板(马口铁)冷轧生产中出现的一类新的复杂板形翘曲缺陷,通过测量分析其翘曲位移模态并与常见的板形C翘及L翘等简单板形翘曲缺陷比较而将其命名为反向C翘缺陷,通过力学建模及模拟计算提出该反向C翘类板形翘曲缺陷产生的力学机理——带钢横截面上各点的纵向延伸在厚度方向存在差值并且该差值沿宽度方向呈复杂不均匀分布所导致的带钢复杂弯曲变形行为。在板形同向C翘研究基础上,抽象建立带钢反向C翘的初应变驱动弯曲变形力学模型,分别推导建立带钢反向C翘变形的解析模型和样条有限元模型及相应求解算法,两种方法的计算结果可相互验证模型及算法的正确性并都与工厂实际存在的反向C翘现象取得一致。研究揭示带钢板形C翘的变形规律与影响因素,获得板形C翘与带钢纵向延伸在厚度方向的差值沿宽度方向的分布形式的关系,发现当此延伸差值沿带钢宽向呈均匀分布或者对称抛物线分布形式时将对应产生不同曲率及翘高的同向C翘,当此延伸差值沿带钢宽向呈不均匀线性分布或者不均匀单调非线性曲线分布形式时将对应产生不同曲率及翘高的反向C翘,进一步还发现如果此延伸差值沿带钢宽向呈更为复杂的曲线分布形式时将会对应产生更为复杂的C翘模态,计算给出了3种典型对称复杂延伸差分布形式所导致产生的对称周期性C翘模态。将生产中所见的反向C翘和仿真预测到的周期性C翘,纳入本课题组前期研究提出的带钢平直性缺陷分类,建立新的带钢平直性缺陷分类。
A new complex warping deformation defects are appeared in the ultra-thin strip steel(tin plating) cold-rolled production. This paper focus on this issue, we name it reverse C-warped defect through the modal analysis of its warping displacement and comparing with some common simple warping defects such as C-warped and L-warped defect. Through mechanical modeling and simulation calculation, we propose the forming mechanism of reverse C-warped defect, and point out that it is caused by the difference of longitudinal extension along the thickness direction on the cross section of strip steel and this difference is unevenly distributed along the width direction of strip steel. Based on the research of C-warped defect, through establishing the mechanical model of the reverse C-warped deformation caused by initial strain on the strip steel, we establish the analytical model and the spline finite element model of the reverse C-warped deformation and get the corresponding algorithm. The calculation results from two methods can checked with each other and are consistent with the actual reverse C-warped defect in manufacturing procedure. This paper reveals the laws of C-warped deformation and the factors that influence them, and get the distribution(along the width direction of strip steel) of the difference between the longitudinal extension along the thickness direction of the strip steel and C-warped defect. When the difference distribution is uniform or symmetric parabolic along the width direction of strip steel, the C-warped defect with different curvature and height will be generated accordingly; when the difference distribution is linear or monotone nonlinear along the width direction of strip steel, the reverse C-warped defect with different curvature and height will be generated accordingly; and when the difference distribution is a more complex curve along the width direction of strip steel, the more complicated C-warped defect will be generated accordingly. Three kinds of symmetric periodic C-warped defect model
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2018年第12期184-192,共9页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(51575040)
