产业链动态联盟信息平台的构建

简介了产业链动态联盟概念,同时阐述了构建产业链动态联盟信息平台的必要性,主要建立了基于网络环境下的产业链动态联盟信息平台构架,分析了平台的信息管理模式及运行模式以及构架中的企业窗口、通用平台、资源平台的功能和信息平台运行流程,最后阐述了平台的应用前景.     

CAD/CAE公共技术服务平台研究与设计

对CAD/CAE公共技术服务平台功能目标进行了分析.在此基础上,设计出了平台的系统结构,并描述了平台各层的结构.通过对平台功能定位分析,提出了平台的组织结构,阐述了平台的主要关键技术,进行了门户网站的开发实现.     

变截面悬臂梁型升降平台的线刚度配置与设计

根据特定环境与接口尺寸分析了国内激光核聚变装置下装光机模块升降平台的设计要求,构建了升降平台力学计算模型,推导了求解变截面悬臂梁型升降平台的线刚度公式。结合边界条件应用公式计算了升降平台主要结构参数和开展了平台线刚度配置,运用ANSYS软件构建了升降平台3维模型和开展了结构分析,验证了平台刚度配置的合理性。最后将研究成果应用于某系统的垂直举升机构样件制作。     

基于SCARA机器人铣削一体化仿真平台的开发

针对传统的卧式铣床在加工工件时存在加工效率较低等缺点,介绍了一种构建机器人铣削一体化平台的虚拟仿真方案。介绍了平台设计理念,设计了旋转刀库等铣削一体化平台的三维仿真模型,分析了构建铣削一体化平台的流程,进而设计了平台动态Smart组件,编制了RAPID程序,机器人运行轨迹表明编程已达到仿真预期效果。该设计方案可以为实体机器人铣削一体化平台的设计提供验证依据和研究平台。     

一种六自由度海浪模拟并联平台的零点标定与性能评估

针对并联机器人中存在的运动精度欠缺的问题,对一种用于海浪模拟的六自由度并联平台进行了零点标定与性能评估。确立了并联平台的运动控制模型,通过齐次坐标方法建立了该并联平台的运动学反解,并且在运动学反解的基础上采用边界搜索法确定了平台定姿态时的工作空间。采用"PC机+运动控制卡"的控制模式对该平台进行了运动控制系统的设计,实现了并联平台的运动控制。首先运用矢量推导法建立了平台的零点误差模型,然后借助于激光跟踪仪对平台进行了零点标定,提高了平台的运动性能。最后针对特定的海浪谱,利用该平台对其进行了模拟实验,并根据实验结果对平台的跟踪性能进行了分析。研究结果表明,经过零点标定后的并联平台能够很好地对海浪进行跟踪模拟。     

海洋平台的运动对人体动力学响应的影响分析

基于多体动力学方法建立了人体-海洋平台模型,计算并分析了不同平台激励情况下人体的振动响应,分析了海洋平台运动的频率、振幅等因素对平台上人体工作性能的影响.对预测海洋平台上人体的振动响应,以及开展考虑人机工程学的海洋平台和船舶设计有指导意义.     

车载雷达平台的优化与仿真

研究了雷达平台的优化方法,通过尺寸优化、形状优化分析获得平台的结构形式;分析了平台梁截面尺寸对平台抗弯强度和抗扭强度的影响,采用达尔斐法将平台抗弯强度和抗扭强度的多目标优化问题统一到一个目标函数中,并通过MATLAB仿真平台对雷达平台进行多约束的尺寸优化,获得最优的平台结构尺寸,并建立平台的有限元模型对其优化结果进行仿真,验证优化结果的正确性.     

基于数据融合的数字化电网调度指挥和管控平台

为实现电网业务数字变革,提出了基于数据融合的数字化电网调度指挥和管控平台建设.首先分析了电网调度数字化的内在需求和驱动力.提出了基于数据融合的电网调度数字化指挥平台,分析了平台构建目标,提出了平台架构体系,并根据平台特点,说明了解决信息孤岛、提升共享数据服务、模块化应用等功能.以透明调度指挥模式为特色,提出了数字化指挥平台的实施过程.最后利用某地区平台实施效果对比,说明了指挥平台的有效性.     

CAD/CAE公共技术服务平台研究与设计

对CAD/CAE公共技术服务平台功能目标进行了分析。在此基础上,设计出了平台的系统结构,并描述了平台各层的结构。通过对平台功能定位分析,提出了平台的组织结构,阐述了平台的主要关键技术,进行了门户网站的开发实现。     

1200m半潜式钻井平台运动响应研究

采用中国船级社《海上移动平台入级与建造规范》的设计要求,对工作水深为1200m的深水半潜式钻井平台进行了结构设计,分析了目标平台所受海洋环境载荷的组成及分类,在风、浪、流的联合作用下对平台进行了时域耦合分析,研究规则波与非规则波下的平台运动响应;对比分析了系泊缆预紧力对平台运动的影响,结果表明,带有预紧力的系泊缆能明显抑制平台的运动,即可以通过人为的增加平台阻尼来限制半潜式平台的定位精度,对深水半潜式海洋钻井平台的耐波性设计具有指导意义。     

面向对象的合金钢淬回火热处理CAD系统

在相关研究成果技术集成和创新的基础上,运用Visual Basic6.0工具开发了合金钢淬回火工艺智能决策系统,并 采用有关试验数据进行了验证,结果证明该系统具有可靠的决策功能。     

Mirror surface machining of high-alloy steels by elliptical vibration cutting with single-crystalline diamond tools: Influence of alloy elements on diamond tool damage

Elliptical vibration cutting with single-crystalline diamond tools is applied to mirror surface machining of high-alloy steels such as cold work die steels and high-speed tool steels with a hardness of more than 60 HRC. Although practical mirror surface machining of hardened die steels such as Stavax (modified AISI 420) with a hardness of 53 HRC has been realized with the elliptical vibration cutting, lives of single-crystalline diamond tools are not sufficiently long in machining of some high-alloy steels, that may be caused by a large amount of alloy elements. In order to clarify the influence of the alloy elements on the diamond tool damage, the elliptical vibration cutting experiments are conducted on six kinds of high-alloy steels and four kinds of pure metals which are the same as the alloy elements. Mechanical properties of the alloy steels, i.e. difference in hardness between carbides and matrices, and the number of small carbides, are measured, and their influence on the micro-chippings are investigated. The chemical states of the alloy elements in high-alloy steels are analyzed using an X-ray diffraction (XRD) and an electron probe micro analyzer (EPMA), and their influence on the tool wear is discussed. Based on the investigation, a mirror surface machining of DC53, which has a high hardness of 62.2 HRC and the best machinability in the tested high-alloy steels, is demonstrated, and a mirror surface with a roughness of Rt 0.05 μm is obtained successfully.     

高韧性高耐磨性冷作模具钢的开发与研究

本文将平衡碳理论加以推广,并根据此理论在Cr₁₂ MoV钢的基础上,调整合金元素含量,加入适量稀土,设计出11种不同成分比的合金钢,通过冶炼、热处理、性能实验等的综合研究,找出了最佳合金元素含量。实验结果表明:符合“平衡碳”理论的新型合金钢,其共晶碳化物细小,与Cr₁₂MoV比较,硬度变化不大,但韧性和耐磨性显著增高。     

Load bearing capacity of tool pin during friction stir welding

Although friction stir welding (FSW) is now widely used for the welding of aluminum and other soft alloys, premature tool failure limits its application to hard alloys such as steels and titanium alloys. The tool pin, the weakest component of the tool, experiences severe stresses at high temperatures due to both bending moment and torsion. It is shown that the optimum tool pin geometry can be determined from its load bearing capacity for a given set of welding variables and tool and work-piece materials. The traverse force and torque during friction stir welding are computed using a three-dimensional heat transfer and viscoplastic material flow model considering temperature and strain rate-dependent flow stress of the work-piece material. These computed values are used to determine the maximum shear stress experienced by the tool pin due to bending moment and torsion for various welding variables and tool pin dimensions. It is shown that a tool pin with smaller length and larger diameter will be able to sustain more stress than a longer pin with smaller diameter. The proposed methodology is used to explain the failure and deformation of the tool pin in independent experiments for the welding of both L80 steel and AA7075 alloy. The results demonstrate that the short tool life in a typical FSW of steels is contributed by low values of factor of safety in an environment of high temperature and severe stress.     

基于切削力的PVD涂层刀具性能研究

本文在干式切削条件下,选用钴基硬质合金无涂层数控刀具和钴基硬质合金基体TiAlSiN与TiAlN/Ta涂层数控刀具,分别切削淬火态45钢(52HRC);车削时,采用SW-1车刀空间受力分析仪测量刀具在车削状态下的三向力;结合对被加工件的表面粗糙度测定,探讨TiAlSiN、TiAlN/Ta涂层刀具在相同条件下的三向力、摩擦力和摩擦系数与无涂层钴基硬质合金刀具的差异。结果表明,在车削高硬度材料时,涂层及其成分对车刀三向力和摩擦系数均有较大影响,TiAlN体系中加入稀土元素Ta形成的TiAlN/Ta多层涂层刀具的三向力、摩擦系数明显小于TiAlSiN涂层刀具,而且被加工件的表面粗糙度更小。     

钢搅拌摩擦焊接及加工研究进展

自搅拌摩擦焊发明至今,国内外开展了大量的有关搅拌摩擦焊(Friction stir welding, FSW)技术的研究与开发工作,并且已在轻合金结构制造领域得到大量实际应用。此外,基于搅拌摩擦焊原理发展而来的另一项技术--搅拌摩擦加工也得到广泛关注,并且在金属材料组织改性及复合材料制备方面显示了独特的优势。然而,由于受到高温搅拌头材料的限制,对钢铁材料搅拌摩擦焊接及加工的研究相比铝合金要少了很多。本研究对钢铁材料搅拌摩擦焊接及加工的研究进展进行简要概述,总结同质钢铁材料搅拌摩擦焊接、异质钢铁材料搅拌摩擦焊接、钢铁材料搅拌摩擦加工以及高温焊接工具材料等几方面的研究成果,指出其中存在的重要科学及技术问题,并对钢铁材料搅拌摩擦焊接以及搅拌摩擦加工的发展趋势及值得关注的问题进行展望。     

涂层刀具高速铣削淬硬钢的声发射信号特征

通过测量不同涂层铣刀高速铣削不同硬度淬硬钢材料时的声发射信号和切屑形态,得到了电压-时间声发射信号以及声发射信号RMS值与切削工艺参数之间的关系。研究结果表明：声发射信号与淬硬钢材料硬度、刀具涂层类型及工艺参数有关;声发射信号可用来评价淬硬钢材料硬度的变化,随着淬硬钢材料硬度的增大,采集的声发射信号电压值呈逐渐增大的趋势;TiAlN涂层产生的锯齿形切屑的剪切带长度最小,切屑易于折断,从而导致其产生过程中的声发射RMS值偏小;随着切削速度和每齿进给量的增大,TiSiN、TiAlN、AlCrN和CrSiN四种涂层铣刀的声发射信号均快速增大,而随着轴向和径向铣削深度的增大,4种涂层铣刀的声发射信号变化不明显;在同一种切削参数条件下,可根据淬硬钢切屑变形特征的变化来间接评价刀具涂层的切削性能;声发射信号波形图的峰值大小可较好地反映锯齿形切屑的生成状态,进而可用来监控淬硬钢加工过程切削稳定性。     

Tribological properties of powder metallurgical tool steels used in powder compaction pressing dies

The tribological properties of two powder metallurgical (PM) tool steels, high and low nitrogen containing, are investigated by means of three different wear tests: ball‐on‐disc, rubber wheel and scratch test. The ball‐on‐disc tests showed two distinct friction curves corresponding to each material. In order to simulate the tribosystem existing in metal powder compaction dies, the rubber wheel and the scratch test were modified. The rubber wheel test was performed using ferrous powder instead of sand, and scratch testing was carried out by sliding a powder compact over the tool steels. The scratch tests indicated a higher steady‐state coefficient of friction for the low nitrogen containing PM steel as compared with the high nitrogen containing alloy. Additionally, the results from the rubber wheel tests were in agreement with industrial experiences, showing the low nitrogen containing tool steel to suffer from severe galling. Copyright © 2011 John Wiley & Sons, Ltd.     

Über den einfluss der oxydationseigenschaft von stählen auf ihren verschleiss-mechanismus durch gleitreibung bei raumtemperatur

Wear of various steels by sliding friction was studied at ambient temperature. Microscopic oxidation characteristics of the steels and the humidity were considered. The specimen materials were low carbon steels, alloy tool steels for hot working, and heat resisting steels with good microscopic oxidation properties and high carbon steels with poor microscopic oxidation properties. Wear tests were made with the “ōkoshi” Rapid Wear Testing Machine in which flat specimens are rubbed on a disk-shaped specimen under a load of 2.1 kg. The sliding distance was 66.6 m, and the sliding speeds were about 0.05 m/s to 3.6 m/s. Wear tests on some materials were made on different days in order to study the influence of the atmosphere. The results that were dependent on the sliding speed showed various forms of curves at the maximum of wear; sharp peaks or rounded peaks. The results are discussed in relation to the microscopic oxidation properties of each steel and the humidity.     

Surface crack susceptibility of electrodischarge-machined steel surfaces

This study investigates the correlation between the surface cracking susceptibility of seven common engineering steels (JIS SKS93, SNCM439, SCM440, SKS2, SK2, SKH51, and SKD11) and the major electrodischarge machining processing parameters, namely the pulse current and the pulse-on duration. The results reveal that the susceptibility of the working materials to surface cracking can be reduced by increasing the pulse current or shortening the pulse-on duration. Furthermore, it is shown that steels with a lower carbon equivalent index or a higher thermal conductivity are more resistant to crack formation. Overall, the steels considered in this study can be ranked in terms of an increasing surface cracking susceptibility as follows: low alloy steel, carbon tool steel, high speed steel, and cold working steel.