首钢京唐1580mm热连轧精轧区温度模型及应用

介绍了首钢京唐1580mm热连轧生产线精轧区设备布置、精轧区温度设定模型及其关键算法。该精轧区温度模型计算区域划分细致,并考虑了带钢表面氧化铁皮、带钢相变及变形热的影响,现场生产表明,模型计算精度较高,带钢头部终轧温度已控制在±15℃偏差范围内,达到了设计指标要求。     

复合小型轧机中精轧机组改造

介绍了长城特钢四厂复合小型轧机中、精轧机组改造前后的概况，重点介绍了改造后的中、精轧作业线的布置，及控制冷却线的特点。并指出试生产中存在的问题和今后发展方向。     

一种设计张减机精轧孔型的经验方法

本文将张减机精轧孔型传统设计方法与德方资料比较后，介绍了一种设计精轧孔型的经验方法──椭圆度、宽展值分配法。     

张减机精轧孔型设计

本文简单介绍了德国引进资料中张减机精轧孔型设计方法,然后详细阐述了设计精轧孔型的一种经验方法—“椭圆度、辊缝充满度分配法”的设计思想和方法。     

精轧管管坯准备的工艺试验

介绍了承德钢铁股份有限公司钢管厂利用现有生产设备,以冷拔方式为精轧管提供管坯的生产工艺试验方案及试验过程。通过三种工艺试验效果的比较分析,确定了一种能满足精轧管管坯要求的较为合理的生产工艺。     

基于数据挖掘的厚板标准精轧道次模型研究

为了提高某厚板厂轧制产品的质量和轧机运行的稳定性,提出了利用决策树算法建立厚板精轧过程道次分配模型的新方法。该方法采用高维度数据可视化和数据挖掘对厚板精轧阶段的原始数据进行分析和挖掘,建立适应标准厚板轧制机组精轧道次的数据模型,实现厚板精轧道次规程的标准化,并为厚板精轧过程的限制参数提供推荐值。经现场模拟与在线应用,该厚板精轧标准道次模型有效地提高了轧制产品质量的稳定和轧机运行的安全。     

一种新型高速线材生产方案

介绍了一种新型高速线材生产线的工艺布置和工艺特点,该生产线在中轧与精轧之间设有一个缓冲集卷装置,中轧后采用脱头轧制,不仅有利于成品的组织性能,而且可大大节省投资。     

精轧温度对含铌、硼Cr17薄板成形性及表面皱折的影响

通过光学显微镜、X射线衍射及背散射电子衍射技术,研究了精轧温度,即高温精轧和低温精轧,对含Nb、B的超纯Cr17铁素体不锈钢薄板成形性及表面皱折的影响。结果表明：低温精轧有利于得到细小及均匀的冷轧退火组织。低温精轧有利于改善冷轧退火板织构的均匀性,促使冷轧退火板得到均匀、规则的γ纤维再结晶织构并形成更少的取向晶粒簇。因此,低温精轧是显著改善冷轧退火板成形性能及抗皱折性的有效工艺。     

小型轧钢车间连续化改造尝试

分析了宣钢轧钢厂横列式小型轧机改造的必要性；介绍了粗轧为５２０ｍｍ×２横列式布置，中轧为４００ｍｍ×６配辊连轧，精轧为３００ｍｍ×４成组活套连轧的简易半连续改造方案。     

热连轧薄带钢头尾窄尺的原因分析及改进

针对日照钢铁控股集团有限公司热连轧薄规格低碳钢带头尾窄尺问题,结合实际生产工艺研究了粗轧、精轧设定,活套、卷取张力对带钢窄尺的影响.通过改善粗轧控宽、精轧模型设定、精轧张力设定和卷取张力设定,有效提高了热连轧薄带钢的尺寸精度,为薄规格带钢生产提供了技术依据.     

Study of magnetic field assisted mechanochemical polishing process for inner surface of Si3N4 ceramic components: Finishing characteristics under wet finishing using distilled water

This study discusses the finishing characteristics of a magnetic field assisted mechanochemical polishing process using Cr₂O₃ abrasive mixed with magnetic particles in the case of wet finishing using distilled water, which was proposed for internal finishing of Si₃N₄ fine ceramic tubes. It was clarified that a highly accurate finishing can be achieved more efficiently in the case of wet finishing using distilled water compared with dry finishing. Moreover, those conditions necessary to achieve high efficiency finishing are discussed.     

超声研磨Al2O3陶瓷材料的表面粗糙度特征研究

通过对Al2O3陶瓷工件的普通及超声研磨实验，分析了超声研磨加工中各个加工参数和陶瓷工件表面粗糙度的相互关系，得出径向超声振动研磨达到最佳表面粗糙度的工件转速为120～260r／min；径向超声振动研磨要得到最佳表面的研磨压力在450N左右，过大或过小均可引起表面粗糙度恶化。在相同转速和相同压力下，超声研磨工件的表面粗糙度较普通研磨工件的小；当转速较小时，W5与W20研磨的表面粗糙度变化不大，随着转速升高，粗糙度先变小后变大，在n=250n/min左右Ra值最小。研究结论为高效研磨Al2O3陶瓷提供了依据。     

Design and development of nanofinishing process for 3D surfaces using ball end MR finishing tool

A new precision finishing process for nanofinishing of 3D surfaces using ball end MR finishing tool is developed. The newly developed finishing process is used to finish ferromagnetic as well as nonmagnetic materials of 3D shapes using specially prepared magnetorheological polishing (MRP) fluid. The existing MR finishing devices and methods are likely to incapable of finish 3D intricate surfaces such as grooves in workpiece or complex in-depth profiles in the mold due to restriction on relative movement of finishing medium and workpiece. In this newly developed finishing device, the ball end MR finishing tool is used for finishing different kinds of 3D surfaces, as there is no limitation on relative movement of finishing medium and workpiece. It can finish the work surfaces similarly as the machining of 3D surfaces by CNC ball end milling cutter and open a new era of its applications in future. The developed process may have its potential applications in aerospace, automotive and molds manufacturing industries. A computer controlled experimental setup is designed and manufactured to study the process characteristics and performance. The magnetostatic simulations were done on ferromagnetic as well as nonferromagnetic materials of 3D surfaces to observe the ball end shape of magnetic field at the tip of the MR finishing tool. The experiments were performed on flat EN31 and groove surface of copper workpieces in the developed MR finishing setup to study the effect of finishing time on final surface roughness.     

钛合金管内表面的电化学磁力研磨复合光整试验

针对热挤压成型对钛合金管的内表面会产生微裂纹、褶皱、毛刺等表面缺陷的问题,提出了一种高效率的电化学磁力研磨复合光整加工方法。设计了电化学磁力研磨复合光整加工的实验装置,分别与纯磁力研磨加工和纯电化学加工进行了光整加工试验对比,检测分析了不同工艺加工前后表面的粗糙度、微观形貌、摩擦磨损行为、表面残余应力和能量谱。结果表明:在相同的加工时间内,与单纯电化学加工和磁力研磨加工相比,电化学磁力研磨复合光整加工的表面粗糙度Ra可达到0.2μm,材料去除量和加工效率显著提高;表面显微形貌要明显优于其他两种加工方式;且加工后表面很好地维持了原有材料的化学成分和表面性质;能够使表面由拉应力转变为约–200 MPa的压应力状态,从而获得更好的表面应力状态。     

基于并联机器人模具型腔磁力研磨光整加工

为了实现复杂曲面模具表面高质量高效率磁力研磨光整加工,进行磁力研磨光整加工的实验研究,对复杂曲面模具自动化磁力研磨光整加工进行了初步探索;从理论上研究了自由磨粒磁力研磨光整加工的机理与特点,并针对不同形状的加工对象,实验研究了磁感应强度、研磨间隙、磨粒粒度以及研具表面形状对磁力研磨光整加工的影响及其变化规律     

Technique of pulse electrochemical finishing in molds and dies

Surface finishing is one of the most important processes in mould and die making. This process is necessary not only for smoothing the surface of die or mould, but also for removing the surface layer, which has been damaged by the preceding machining process and finally improve the performances and lifetime of moulds to a large extent. It has been reported that between 30% and 40% of the total time required to manufacture a die or mold is spent on finishing operations, most of which are performed by skilled workers employing traditional techniques. At present, key problems in mould and die finishing technology can improve the finishing efficiency, consistency and quality at reduced costs. A new and high efficiency unconventional finishing technology, pulse electrochemical finishing was introduced. Experiments were done in neutral nitrate electrolytes. The influence of electrolyte composition, intereletrode gap, finishing time, flow quality, current density, compositions of steel materials and pulse parameters on the resulting surface finishing was investigated. Results indicate that pulse parameters have important influence on operations finishing and the proper selection of pulse parameters can lead to both good smoothing efficiency and surface quality at low costs.     

我国热带精轧机引进弯辊和轧辊横移装置结构简述

本文以宝钢2 050 mm热带钢精轧机、武钢2 250 mm热带钢精轧机、沙钢1 700 mm热带钢精轧机、国丰1 450 mm热带钢精轧机中的弯辊和轧辊横移装置为例, 介绍了我国热带钢精轧机引进弯辊和轧辊横移装置的结构特点, 并进行了优缺点比较。     

Simulation for the prediction of surface roughness in magnetic abrasive flow finishing (MAFF)

The final machining (or finishing) of precision parts with high level of surface finish and close tolerance is making the application of magnetic abrasive finishing technology increasingly important. Magnetic abrasive flow finishing (MAFF) is a new abrasive finishing process combining the features of abrasive flow finishing (AFF) and magnetic abrasive finishing (MAF). MAFF provides a high level of surface finish and close tolerances for wide range of industrial application. This paper focuses on the modeling and simulation for the prediction of surface roughness on the workpiece surface finished by MAFF process. A finite element model is developed to find the magnetic potential distribution in the magnetic abrasive brush formed during finishing action and then it is used to evaluate machining pressure, surface finish and material removal. The simulation results are compared with the experimental results available in the literature. The simulated workpiece surface roughness shows features similar in nature to the experimental results.     

Metastable austenitic stainless steel tool for magnetic abrasive finishing

Through selective heat treatment, a metastable austenitic stainless steel tool can be fabricated to exhibit alternating magnetic and nonmagnetic regions. Magnetic abrasive is attracted to the borders of the magnetic regions of the developed tool to create additional finishing points. In combination with a multiple pole-tip system, this unique magnetic property facilitates simultaneous finishing of multiple regions for shortening finishing time. This paper describes the fabrication, the crystalline structure, and the resulting magnetic properties of the heat-treated tool. The magnetic abrasive behavior, the finishing characteristics, and a mechanism to extend the finished length are clarified for internal finishing flexible capillaries.     

发动机缸体铸件的精整工艺与装备

以发动机缸体铸件为例介绍了铸件精整工艺与装备,包括铸件的落砂、去浇冒口、热处理、振击除芯、一次粗抛、铸件表面磨削、人工精整、二次精抛、检验及铸件涂装等。介绍如何选择合理的铸件清理工艺和高端的清理生产装备,以实现铸件清理的连续、自动化生产,从而从真正意义上实现铸造生产从传统的手工、半机械作业走向先进的工业自动化生产。