轧钢机力能参数神经网络预测

在分析轧机轧制过程中的力能参数的基础上 ,测量并计算了 50 0 mm轧机的轧制力。探讨了用神经网络模型确定轧制力的方法 ,预测了轧制力 ,并将三种方法得到的轧制力进行了比较。结果表明用神经网络模型预测的轧制力误差远小于基于传统数学模型计算的轧制力误差 ,它能较好他反映实际轧制过程的特征。     

一种楔横轧模具CAD/CAM特征建模系统的研究

针对楔横轧模具的结构和数控加工的特点，提出把楔横轧模具看作是以楔特征为主要特征的拼合体的建模方法。并且根据该建模方法，建立了楔横轧模具的设计特征和制造特征。     

环件轧制三维有限元模拟中质量缩放方法的运用

阐述了环件轧制三维有限元模拟中运用质量缩放方法的意义及其理论依据,并对显式动力学有限元模拟中各种质量缩放方法进行了分类,给出了环件轧制模拟中质量缩放方法的选取原则。最后基于ABAQUS/EXPLIC-IT操作平台,建立了铅环件的环件轧制三维有限元模型,通过具体模拟及分析比较计算结果对选取原则进行了验证,从而总结出了适合于环件轧制模拟的有效的质量缩放方法。     

Deformation analysis for cold rolling of Al-Cu double layered sheet by physical modeling and finite element method

The deformation characteristics of Al-Cu double layered sheet during rolling with various process parameters were studied by both a physical modeling technique and the finite element method. Physical modeling and the finite element method are complementary, due to their different advantages and limitations. Physical modeling simulates metal forming operations by using a model workpiece under conditions similar to those in actual production. The deformation characteristics of double layered sheet during rolling were also simulated using a commercial finite element code, FORGE?. The effects of process parameters, such as total reduction ratio, initial thickness ratio and differential speed ratio on the rolling characteristics were the primary focus of the investigation. In addition, an analytical model for double layered sheet rolling is also proposed with the use of a force-thickness diagram. From the results, the effect of the process parameters on the rolling of the Al-Cu double layered sheet has been determined.     

基于AMESim与ADAMS联合建模的轧机厚控系统仿真

为了全面研究轧机液压厚控系统动态特性,建立直观真实的虚拟轧机模型,提出基于AMESim和ADAMS联合建模的仿真方法。在ADAMS中构造轧机实体刚柔耦合动力学模型,实现了轧机的负载特性研究;在AMESim中建立液压系统物理模型,实现了液压伺服系统精确建模和分析,两者通过接口实现数据交换,保证了液压系统模拟的准确性和负载系统模拟的真实性。通过联合仿真模型得到了系统实时响应以及出口板厚实时数据,将模型仿真输出数据与实测数据进行比较,证明仿真模型能准确体现系统动态响应,并能体现机械部件在载荷下弹性变形和板厚实时输出情况。     

不同变形区组成下铝合金厚板蛇形轧制板曲率建模分析

蛇形轧制作为一种新型的轧制工艺为高性能厚铝板生产提供了一种新方法,但是传统的异步轧制弯曲曲率模型不能用于蛇形轧制,蛇形轧制缺少精准的轧后曲率计算模型。根据变形区的特征及中性点的位置,确定了变形区组成及其存在边界条件;塑性变形区最多可分成4个区,对不同组成情况的变形区进行了分析,建立了各种情况下单位压力和上、下部分累积剪应变偏差模型,在此基础上建立了剪切应变引起的弯曲曲率模型,根据流动准则建立了轴向应变引起的弯曲曲率模型,最终建立了不同辊径比下的蛇形轧制的弯曲曲率模型。考虑到厚度方向变形的不均匀性,在建模过程中引入均匀系数E,使模型更加精确。采用Ansys模拟和实验数据进行了模型精度的间接验证。结果表明,与模拟和间接实验结果相比,最大和最小相对误差分别为10.71%和0.34%,证实了模型精度,可应用于弯曲曲率预测及控制;同时研究了不同工艺参数（偏移量、辊径比、压下量、工件初始厚度等）对弯曲曲率的影响规律。研究结果为厚规格铝板蛇形轧制生产提供重要理论和技术支持。     

基于激光跟踪仪的支撑辊轴承座检测方法研究

针对马钢板带热轧生产线精轧机支撑辊轴承座受力变形严重,轴承座形位公差失效导致轧辊出现交叉轴的情况,基于某公司AT403激光跟踪仪,利用三维建模的方法对该支撑辊轴承座变形内孔进行模拟测量,通过变形轴承座内孔和标准轴承座内孔的测量数据的分析, 得出了内孔轴线精度对衬板对称度的影响和最佳的检测方法,为板带热轧生产线轧辊轴承座在线精度检测提供了技术支撑。     

A new approach to predicting partial recrystallization in the multi-pass hot rolling process

An exploratory approach to handling partial recrystallization in multi-pass hot rolling where the heterogeneity of steel microstructures is inherent is presented. The proposed model is based on a modification of the conventional model in which the microstructure of deformed austenite at each pass is simply taken as homogeneous during the multi-pass rolling. The usefulness of the modified model is demonstrated by applying it to a four-pass oval-round (or round-oval) rod rolling sequence. The pass-by-pass recrystallized fraction and austenite grain size (AGS) computed from the modified model are compared with those from the conventional model. The result showed that in multi-pass rolling at higher rolling speed, the recrystallization behavior and evolution of the austenite grain size at a given pass was strongly influenced by the modeling method of the partial recrystallization attributed to microstructural heterogeneity.     

Simulation of deformation and temperature in multi-pass continuous rolling by three-dimensional FEM

This paper presents a new method for modeling a rod and wire continuous rolling process. Three-dimensional FE models of the whole rolling process are established by the proposed method that consists of a pushing technique of rigid body and a method of data transfer, and it is utilized to analyze the deformation and the temperature distribution of billet during the multi-pass rolling process. The pushing technique of rigid body is developed to keep the contact status between the deformable body and a rigid body and to push the deformable body forward during inter-pass time. The method of data mapping is adopted to transfer element field variations between meshes of different models by an interpolation function. The model was applied to simulate 18 stands rolling process of a 304 stainless steel and provides an insight into the process by studying the billet deformation and the temperature distribution. It shows fairly good agreement between the predictions and the measured values of temperature.     

AM50镁合金多道次热轧中动态再结晶过程的有限元模拟及实验研究

通过开发用于组织模拟的用户程序，采用有限元软件DEFORM-3D模拟AM50镁合金多道次热轧过程中的组织转变，并通过与实验结果的对比分析证明该用户程序模拟多道次轧制的可行性。结果表明：多道次热轧有助于镁板的晶粒细化及均匀再结晶组织的获得，精轧前的板坯温度对终轧后的晶粒尺寸影响很大，但对晶粒尺寸的分布情况影响不明显。开发的用户程序亦可应用于其他类型多道次热变形过程的模拟研究。     

Dynamic explicit FE modeling of hot ring rolling process

1Introduction Ring rolling is an advanced process typically used to manufacture parts with revolved geometries.It makes use of rotating rolls to press a ring continuously and locally,causing the wall thickness of the ring to reduce,the diameter to expand …     

轧制过程AGC系统的建模新方法及应用

提出了轧制过程ＡＧＣ系统的一种建模新方法,介绍了其在某冷连轧机上的应用及效果,带钢厚度波动从４５μｍ减小到２０μｍ．     

基于振动时域特征的船用滚动轴承故障诊断方法

基于机器学习故障诊断方法,针对船用滚动轴承复合故障特征提取多样化的特点,提出一种以振动信号时域指标为特征的随机森林故障诊断方法。将振动时域信号进行清洗转换,构造5个量纲一化指标的衍生特征,并选取以决策树为基本分类器的随机森林算法建立训练模型;通过特征筛选、评估测试和模型优化得到较为理想的故障诊断分类模型;采用滚动轴承竞赛数据集进行模型仿真,并结合实际模拟8种船用滚动轴承故障状态。通过三向振动实验和算法建模,证明特征提取的科学性和故障诊断模型的有效性。结果表明:采用该方法,数据仿真诊断准确率为98.61%,实验诊断准确率为98.85%,且该方法在振动采集方向为轴向时诊断效果最优。     

基于三维实体模型的四辊热轧机设计

根据热轧粗轧机的特点,采用了三维实体建模技术对某热轧生产线轧机区主要设备进行了三维实体建模,并对模型进行了装配分析及干涉检查。该方法提高了设计准确性和设计效率,节省了设计时间。     

Design of rolling pass schedules to improve grain-size uniformity in thickness

Among various methods to achieve high strength in plain carbon steel, the method of grain refinement by controlling thermo-mechanical processing parameters has gained a great attention in steel rolling industries. In the present study, three different rolling pass schedules for thick plates are proposed to obtain fine and uniform grains through thickness, based on combined analyses of recrystallization modeling, finite element analysis and experiments. Since meta-dynamic and dynamic recrystallization have been found to be effective in producing fine grains, the reduction ratio and the interpass time were carefully considered in the proposed rolling pass schedules.     

有限元与Monte Carlo方法耦合的冷轧纯铝板再结晶模拟

利用有限元软件ANSYS模拟的冷轧铝板应力场及其相应的储能场，在假设的介观非均匀储能场基础上，考虑冷轧铝板的宏观能量场的非均匀性，实现了金属变形的有限元方法与Monte Carlo再结晶模拟方法的耦合，有效地模拟非均匀储能场基础上的冷轧铝板再结晶过程，结合现有的理论与实验结果，比较和验证了两个极限储能部位的介观结构拓扑组织和再结晶动力学参数，得到较为理想的结果。     

Strength and biaxial formability of cryo-rolled 2024 aluminium subject to concurrent recovery and precipitation

The precipitate-hardenable aluminium alloy 2024 has been processed by rolling to develop a fine microstructure. Four alloy conditions were tested; these included two rolling temperatures and two different ageing sequences. For all four conditions there was an ideal heat-treatment time at which there was a concurrent improvement in both strength and formability. Microstructural modeling has shown that this is the result of a small processing window in which the hardening due to precipitation is larger than the softening due to recovery, while the detrimental effects of particle coarsening on ductility have not yet developed. Cryo-rolling and room-temperature rolling produced materials with similar strengths, but cryo-rolling showed inferior formability. Natural ageing before rolling significantly decreased the formability compared to rolling in the supersaturated condition, and it is proposed that the solute clusters that develop during natural aging inhibit dynamic recovery and consequently increase the dislocation density that develops during rolling.     

Application of mathematical modeling in two-stage rolling of hot rolled wire rods

The no-recrystallization temperature (T_nr) is an important parameter in the design of two-stage rolling schedule to obtain finer grain size. T_nr was obtained both by continuous cooling compression testing and tension-compression testing. However, due to the limitations of experimental installation, both compressing testing and tension-compression testing have a scaling down of practical pass strain and strain rate in rolling mill. The mathematical model that calculates mean flow stress (MFS) can eliminate these limitations and the pass strain and strain applied in mathematical model are approximately equal to the mean value of that in wire-rod rolling mill. Therefore, mathematical calculation is a new method to determine T_nr and the predicted T_nr is similar to experimental results. Due to the high strain rate and short interpass time at the finishing strain of wire rods mills, mathematical modeling is also an effective method to simulate microstructure-evolution in wire rods rolling. An expert system was established to study the microstructure evolution in two-stage rolling through the obtained dynamic recrystallization (DRX) model combined with metadynamic recrystallization (MRX) and static recrystallization (SRX) model in literature. In the present work, it is simplified that the complete metadynamic recrystallization (MRX) is achieved when strain for deformation exceeds critical strain ɛ_c. It was found that strain accumulation played an important role in finishing rolling. The recrystallization behavior during finishing rolling stage was repeated by static and dynamic model. The predicted austenite grain size and mean flow stress at each pass are expected to provide guidance for appropriate rolling schedule design.     

滚动轴承疲劳失效故障的数字孪生虚拟实体建模

针对目前基于数据驱动和机制建模的滚动轴承故障诊断方法的不足,提出一种针对疲劳故障的滚动轴承数字孪生虚拟实体模型。基于L-P疲劳失效理论,对滚动轴承全寿命周期的振动响应进行建模。在轴承五自由度非线性滚动振动模型的基础上,考虑滚动体-滚道冲击力的影响,对滚动轴承内、外圈局部缺陷模型进行改进,并提出一种滚动轴承次表面裂纹早期故障模型,从而建立了疲劳失效下的滚动轴承全寿命数字孪生虚拟实体模型。该模型可表征轴承疲劳故障的产生、发展到严重的全过程。对不同类型的轴承疲劳故障虚拟实体数据进行了分析,验证了所建模型的正确性和有效性。     

楔横轧模具的数字化设计关键技术

重点阐述了楔横轧模具数字化设计中有关数字化建模技术、基于知识的设计、并行设计、逆向工程、虚拟设计技术等关键技术.提出了面向制造的特征建模和面向性能分析的特征建模;运用知识工程表示楔横轧模具事例库,并挖掘其内在的规律;采用并行技术,实施楔横轧模具设计与分析的并行、设计与制造的并行;引入虚拟设计思想,构建楔横轧模具的虚拟环境,利用数字化建模阶段产生的信息模型,在三维虚拟环境中对模具进行虚拟装配和虚拟加工.