【作者】 俞俊杰；

【导师】 陈连生；

【作者基本信息】 河北理工大学 ， 材料加工工程， 2009， 硕士

【摘要】 H型钢具有一种合理的经济断面,与普通的工字钢相比,使用更加方便,而且有很好的经济效益,已广泛应用于钢结构建筑工程和公用基础设施等方面。国外H型钢应用较早,至今已有近百年的历史,应用领域比较广泛;国内的H型钢生产起步较晚,20世纪末,马钢和莱钢先后建设了一条大型和中型H型钢生产线,推动了国内H型钢的发展,现在国内H型钢的生产规模发展迅猛,应用领域逐步扩大。在H型钢的轧制过程中,由于腹板和翼缘相互影响使金属的流动极为复杂,工艺难度很大,生产中易出现多种问题。主要研究了有限元模拟H型钢粗轧过程金属变形规律,为了研究其变形的规律,根据金属成形的变形原理和有限元理论,采用有限元的方法对H型钢的多道次往复粗轧过程进行模拟分析,详细的介绍了有限元模型的建立、材料参数、边界条件、网格的划分,得到了轧件各道次模拟的变形结果。研究过程中,为了得到精确的模拟结果,针对金属形变应力分析的特点,采用了DEFORM有限元模拟手段,较全面地分析了金属形变过程中各个阶段的轧件断面内在压下、宽展、轧制三个方向的应力、应变规律。主要结论如下:异型坯在箱形孔中立轧,轧件较高,变形不易渗透,腹板中部变形量较小,腹板的宽展很小且不均匀。轧件在异型孔中变形时,腹板部位的金属受到压应力,腹板变形量大,翼缘变形量较小,金属在横断面内向翼缘流动的阻力较大,导致腹板沿着轧制方向的延伸较大,最终在头尾形成了腹板的“舌头”状。腹板的延伸较翼缘大得多,翼缘对腹板延伸有一定牵制,翼缘部位金属受到拉应力,腹板部位受到压应力,轧件各部分变形不协调;异形孔中轧件不能很好的充满孔型。在保持辊环宽度一定的情况下,通过增大第三道次孔型内圆角和第八道次侧壁斜度,整个断面变形更加的均匀。研究结果可为H型钢粗轧工艺的改进提供参考,计算方法也为H型钢粗轧过程的数值模拟奠定了基础。更多还原

【Abstract】 H-beam with reasonable and economic cross-section is more convenient and economic in using than the ordinary I-beam, and has been widely used in steel construction, utility infrastructure and other areas. H-beam has been used widely since a long time in overseas; the domestic H-beam production industry began at latter time. MA Steel and LAIWU Steel had put a heavy and a medium H beam production lines into manufacture successively by the end of 20th century, which boosts the H beam production manufacture and application. Up to now, the production of H beam is booming all over the country in large scale and application fields expand step by step. In the hot rolling process of H-beam steel, the interactions of flange and web plate make the flows of metal extremely complicated which makes the process more difficult, and many problems occur likely in production.The research is mainly about the simulation process of rough rolling of hot rolling H-beam steel by Finite Element Method. According to the principle of metal forming and theory of Finite Element Method, the simulation for multi-pass reversing breakdown rolling of H-beam steel was conducted. The establishment of FEM model, setting of material parameters and boundary conditions, and the meshing were introduced in detail. The simulation results of work piece’s deformation after each pass were received.FEM software of DEFORM is adopted according to the feature of deformation stress and stain for accurate results. The rule of the stress and strain distribution of the work piece center part in X\Y\Z direction is completely analyzed. Main results were as follows:There occurs flange’s small deformation and asymmetric lateral spread in middle part of shaped blank due to the height of the work piece and stain’s hard transfer during the rolling on edge.Flange with large scale of deformation caused by compressive stress extends along rolling direction during the deformation of work piece in shaped pass which also caused by resistance in flowing process of metal from inside of the section to flange girth and finally caused the“tongue shape”at front and back of flange.Extension of flange is larger than flange girth. Resistance of flange girth to flange which contains the compressive stress and tensile stress in flange girth causes the asymmetric in different part of work piece. Pass can’t be filled efficiently by work piece. By increasing the filleted corner in the third pass and angle of sides in the eight pass, the deformation of whole section can be more asymmetric in the same roll collar width.The results obtained can offer references to the improvement of H-beam rough rolling process, and the calculation method in the paper also settles the basis on the entire numerical simulation process for H-beam rolling process.更多还原