中 厚 板 轧 制 过 程 的 数 值 模 拟

 基于LS DYNA仿真软件,采用显式算法和隐式算法相结合的方法,对中厚板轧制过程的热力耦合有限元模拟进行了研究。通过仿真,得到了中厚板的应力场、应变场及温度场的分布。根据分析可知轧件表面温度在轧制过程中有所上升,轧件内部到表面形成明显的温度梯度。轧件头部变形较剧烈,在轧制后外端存在明显的预应力区。模拟结果与实测结果比较一致,表明了该数值仿真方法的可靠性。     

软件控制系统在台车式退火炉上的应用

根据台车式退火工艺制度,在软件平台上开发了L1级和L2级控制系统.其中,L1级的控制策略采用增量式PID算法,L2级的核心模型采用引入热电偶的三元模型.该控制系统模拟了台车式退火炉在各阶段的热过程,得到了炉内各元的温度场.另外,系统对升温转保温阶段进行了处理,通过两种方法保证了过渡过程的稳定性.     

双机架紧凑式可逆炉卷轧机板材热连轧的温度场有限元研究

本文实现了对国内唯一一架双机架紧凑式可逆炉卷轧机板材热连轧的温度场有限元研究。采用弹塑性大变形热力耦合有限元法研究板材热连轧过程。利用有限元理论建立了板材热连轧模型，应用MSC／MARC软件进行计算，重点分析了轧制过程和变形区中轧件的温度场分布和变化。计算结果与实际生产情况相吻合，同时表明有限元理论可以实现对板材热连轧过程的数值模拟。     

双机架紧凑式可逆炉卷轧机板材热连轧的温度场有限元研究

实现了对国内唯一一架双机架紧凑式可逆炉卷轧机板材热连轧的温度场有限元研究。采用弹塑性大变形热力耦舍有限元法研究板材热连轧过程。利用有限元理论建立了板材热连轧模型，应用MSC／MARC软件进行计算，重点分析了轧制过程和变形区中轧件的温度场分布和变化。计算结果与实际生产情况相吻合，同时表明有限元理论可以实现对板材热连轧过程的数值模拟。     

基于钻孔数据的地质体隐式建模约束规则自动构造方法

针对隐式建模约束规则构造自动化程度较低的问题,提出了一种基于钻孔数据进行地层特征参数自动提取与量化的方法。首先通过分析原始钻孔数据自动提取地层产状来表征地层的全局插值趋势;然后利用局部椭球体搜索邻域钻孔群来构造局部插值趋势,按照不同的搜索策略提取邻域边界点集;最后将构造的约束数据应用于基于径向基和克里金的2种隐式建模插值方法。试验结果表明：该方法兼顾了钻孔数据的异向性,能够很好地模拟沉积层和侵入体,且模型准确性好,符合地质学家的认知规律。     

用显式动力学有限元法分析压下率对板带轧制压力分布的影响

采用大型商用显式动力学有限元分析软件Ansys/LS-DYNA模拟了板带轧制过程，所计算的变形区轧制压力分布与相关实验结论符合较好，证明显式动力学有限元法可有效地用于分析板带轧制压力分布。     

方进椭型钢轧制变形过程三维有限元模拟

应用MARC／autoforge商用有限元软件，对方轧件在椭圆孔型中的轧制变形过程进行热力耦舍模拟。研究了模拟过程中的轧件温度场的分布及变化规律以及轧制能力参数在轧制过程中的变化。分析计算说明，采用有限元模拟的方法可以较好地反映金属的实际变形情况。     

浸入式水口浇钢过程中热应力耦合场分析

运用有限元分析法模拟了浸人式水口实际预热后的温度场以及浇钢过程中的瞬态温度场和热应力场的分布.结果表明:浸人式水口在浇钢过程中突然受到高温钢水的冲击,在短时间内温度变化剧烈,水口颈部至上表面温度变化明显,且呈阶梯状分布;水口与钢水接触的内壁热应力值很小,外壁热应力大于内壁,随着浇钢时间的增加,热应力分布范围沿水口径向逐...     

数值模拟在汽车板成形中的应用

在汽车和冶金工业中,板成形数值模拟广泛地应用于零件的选材和模具的设计.文章论述了板成形数值模拟的基本方法及其发挥的重要作用,并采用动力显式有限元软件DYNA3D对轿车顶板的冲压成形过程进行仿真计算,分析了成形安全裕度.     

热轧三机架连轧轧板过程的二维有限元模拟

应用MARC／AutoForge有限元软件，对轧件在三机架连轧变形过程进行热力耦合模拟。研究了模拟过程中的轧件温度场的分布及变化规律以及轧制力能参数在轧制过程中的变化。分析计算说明，采用有限元模拟的方法可以较好地反映金属的实际变形情况。     

3D FE Analysis of Thermal Behavior of Billet in Rod and Wire Hot Continuous Rolling Process

 An FE model was developed to study thermal behavior during the rod and wire hot continuous rolling process. The FE code MSCMarc was used in the simulation using implicit static arithmetic. The whole rolling process of 30 passes was separated and simulated with several continuous 3D elastic plastic FE models. A rigid pushing body and a data transfer technique were introduced into this model. The on line experiments were conducted on 304 stainless steel and GCr15 steel hot continuous rolling process to prove the results of simulation by implicit static FEM. The results show that the temperature results of finite element simulations are in good agreement with experiments, which indicate that the FE model developed in this study is effective and efficient.     

高速线材生产过程组织性能预测模型仿真

 采用计算机对高速线材生产过程进行模拟，开发出具有较高准确度同时具有对不同轧制工艺有较好通用性的高线生产仿真系统。利用有限元方法计算了线材在待轧、轧制、水冷及风冷过程的温度场；通过对再结晶动力学模型的解析，得到了静态再结晶、动态再结晶的分数以及奥氏体晶粒在轧制过程中的变化情况；通过组织演变模型和温度模型的耦合计算，模拟出斯太尔摩风冷线上线材的组织变化过程；建立了利用初始化学成分和组织组成预测高线产品力学性能的BP神经网络模型，通过生产过程数据的训练，实现了对线材力学性能的预测。仿真计算的结果对线材控轧、控冷工艺的改进有一定的指导意义。     

Analysis of Metal Forming in Two-Roll Cross Wedge Rolling Process Using Finite Element Method

A simulation model for two-roll cross wedge rolling (CWR) was presented by using three-dimensional rigid-plastic finite element method (FEM).The whole forming process of CWR,including knifing zone,guiding zone,stretching zone,and sizing zone,was simulated using the model in which dynamic adaptive remeshing technology for tetrahedral solid elements was used to fix element distortion.Based on the simulation results,the distributions of metal flow field,strain field,and damage field,and the geometry of the workpiece's end were analyzed.These results could provide theoretical guidance for realizing net shaping and reasonable design of tools.     

高速线材减定径多道次孔型轧制有限元分析及工艺参数优化

采用显式动力学有限元方法对高速线材减定径多道次孔型轧制进行了模拟分析。通过模拟计算的结果,分析了各道次轧件在轧制过程中的宽展变化、等效应变及残余应力的分布、各道次轧制过程中的轧制力及道次间张力变化。根据分析结果,对轧制工艺参数进行了优化,通过调整工艺参数,各道次轧件断面得到了优化,各道次间实现了微张力连轧关系。     

冷轧带钢轧制力高精度快速仿真模型的研究

采用微分单元法，考虑了轧辊和轧件的弹性变形，导出了冷轧生产中的轧制压力模型，避免了复杂的微分方程求解。同时采用有限元法对经典轧辊压扁半径和变形区长度公式进行修正，汲取了有限元法的准确性和解析模型快速性的优点。此模型采用较小的自适应系数即可用于实时动态仿真。仿真结果与轧制压实测值吻合较好，该模型在冷轧生产中具有重要的意义。     

热连轧粗轧区立轧轧制力在线模型研究

  针对热连轧粗轧区立轧轧制力在线模型预报精度低的问题,采用有限元软件DEFORM模拟了板坯热连轧粗轧区立轧过程,分析了板坯立轧过程轧制力预报精度低的原因。通过对有限元模拟结果的分析,给出了板坯立辊轧边时计算变形程度的新方法,并通过回归得到了适合板坯立轧轧制力计算的外端应力状态影响系数公式,进而得到了新的轧制力计算公式。经与现场实测数据比较,明显提高了立轧轧制力的预报精度。     

Spatial Vibration and Its Numerical Analytical Method of Four-high Rolling Mills

The rolls in contemporary four-high mills cannot be maintained parallel during the rolling process. There- fore, four-high rolling mill vibrations take place in six degree of freedom （DOF） leading to spatial behaviors invol- ving vertical, horizontal, axial, torsional, cross and swinging vibration modes resulting in complex relative motions between the rolls. Two numerical methods, modified Riccati-transfer matrix method （Riccati-TMM） and finite ele- ment method （FEM）, are presented to analyze a spatial vibration characteristic of two four-high rolling mills with different stability. The natural frequency and mode shape of four-high rolling mills are obtained, and the clearance has a great effect on natural frequency and mode shape. In addition, field testing experiment is also conducted to measure natural frequency by power spectrum analysis of rolling mill vibration. Experimental results basically agree with those calculated by Riccati-TMM and FEM, which means that the Riccati-TMM and the FEM can be used for analysis of spatial vibration of four-high rolling mill. Meanwhile, the spatial vibration shows more compound vibra- tion behaviors and the negative effect of horizontal, vertical, cross and swinging vibration modes are effectively con- trolled after redesign of rolling mill. These advantages have a great significance for the rolling mill to be operated with a much higher rolling speed and improved yield of products.     

Modelling a Skin-Pass Rolling Process by Means of Data Mining Techniques and Finite Element Method

 An experience is presented using the finite element method (FEM) and data mining (DM) techniques to develop models that can be used to optimize the skin-pass rolling process based on its operating conditions. A FE model based on a real skin-pass process is built and validated. Based on this model, a group of FE models is simulated with different adjustment parameters and with different materials for the sheet; both variables are chosen from pre-set ranges. From all FE model simulations, a database is generated; this database is made up of the above mentioned adjustment parameters, sheet properties and the variables of the process arising from the simulation of the model. Various types of data mining algorithms are used to develop predictive models for each of the variables of the process. The best predictive models can be used to predict experimentally hard-to-measure variables (internal stresses, internal strains, etc) which are useful in the optimal design of the process or to be applied in real time control systems of a skin-pass process in-plant.     

中厚板轧制过程智能化温度预报模型

 采用有限元(FEM)程序模拟计算了中厚板轧制过程中的温度变化,得到与实测温度符合甚好的模拟结果。以模拟计算结果为基础,建立了BP神经网络和回归温度预报模型。采用两种模型对中厚板热轧过程中轧件表面温度变化情况进行了预报。结果表明,神经元网络模型的预报值较回归模型更接近FEM模拟计算值和实测值,可将神经元网络模型应用于中厚板轧制过程中轧件表面温度变化的在线预报。