快速原型制造中的前期数据准备

介绍了快速原型技术的原理和实现过程,对快速原型制造中的前期数据准备工作,快速原型机的输入数据来源、三位模型数据的近似处理、三维模型数据切片处理作了详细讨论.     

航空钣金数字化快速工艺准备系统的研究与开发

提出面向飞机钣金精准制造的数字化快速工艺准备系统的设计思想,构建其系统框架,分析了以CATIA平台为核心的系统集成与数据管理方式。设计与开发了快速工艺准备系统的子系统——模面快速设计与优化系统、快速工艺分析系统和工艺知识库系统。以橡皮成形工艺为例,介绍了系统开发和应用情况。     

基于现代制造理念的数字化敏捷工艺准备系统研究

根据制造行业CAX技术发展的趋势以及现代集成制造系统CIMS发展中的瓶颈,提出了数字化敏捷工艺准备的概念.同时,给出了数字化敏捷工艺系统的总体结构,并讨论了该系统的主要功能.为协助国防企业快速重组生产、提高其快速反应能力及推进其信息化进程奠定了良好的基础.     

快速原型制造的模型数据准备

模型数据准备是快速原型制造的重要环节，本介绍了快速原型的技术原理以及反求工程、网络传输、CAD技术及切片技术在光固化快速原型制造的模型数据准备中应用的情况。     

EROWA柔性工装在惯性平台制造中的设计与应用

EROWA柔性工装因其高柔性、高精度、高效率等特点在装夹方面拥有突出优势。惯性平台关键结构件因其高精度、弱刚性、微型化、结构复杂等特点对精密制造技术提出了更高的要求。基于柔性工装技术,阐述EROWA柔性工装在惯性平台制造过程中的设计与应用。该技术在装备的变批量生产过程中具有重要意义。     

快速制造技术的最新进展及其发展趋势

自20世纪80年代以来,快速制造(RM)技术一直保持着迅速发展的势头.首先概要地分析了这种高新技术之所以持续发展的原因,然后介绍了快速制造技术的最新进展,最后分析了快速制造技术的发展趋势.这些新成果、新进展必将使RM技术成为21世纪现代制造技术的主要发展方向之一.     

面向动态制造资源的工艺设计

网络化制造为研制为主的制造企业(主生产单位)提供了一个快速制造平台,面对自身制造能力的不足,通过网络快速整合扩散企业的制造资源,实现主生产单位生产批量的快速扩充。针对扩散企业制造资源不同模型的问题,定义了统一的工艺制造资源模型。主生产单位再根据动态制造资源以及较强的工艺规划能力进行二次工艺设计,缩短了工艺生产准备时间,保证了外加工任务的质量,能够满足主生产单位快速响应制造的需要,也为网络化CAPP提供了一种新的思路。     

基于等离子弧焊的金属零件直接制造系统设计

金属零件直接制造技术目前已成为快速成形技术的研究热点和重要发展方向.基于等离子弧焊的金属零件直接制造技术是一种非常实用而且制造成本较低的直接快速制造金属全密度零件的方法.在分析金属零件直接制造原理的基础上,设计并开发了基于等离子弧焊的金属零件直接制造软、硬件系统,并采用该系统进行高温合金中空零件制造实验.实验结果表明,采用等离子弧焊直接制造系统可以得到成形良好、组织细密的金属零件.     

基于CPC和MVPN的快速设计与制造一体化系统的研究

提出了制造专用网（MVPN）的概念，然后以上海大学快速制造工程中心为例，建立了工感动CPC和MVPN的快速设计和制造一体化系统。该系统以CPC为产品数据和信息的集成平台，以MVPN为网络的安全保障，有效地解决了快速设计和快速制造中存在的瓶颈问题，进一步拓展了其应用领域，具有一定的理论和实用价值。     

基于快速成型技术的快速模具制造

分析了基于快速成型技术的快速模具制造技术及其工艺过程,阐述了快速模具制造技术的发展趋势.     

Influence of tool edge preparation on performance of ceramic tool inserts when hard turning

Coating, as a form of tool edge preparation, changes the properties, geometry and roughness of the active parts of tool inserts. The performance of both uncoated and coated ceramics was tested in machining tests and the results were related to the tool edge and the machined surface as well as cost indices. The presented results show that tool edge preparation by coating does affect forces, tool wear and the machined surface, while friction force from scratch tests and the coating thickness and its hardness have been identified as being relevant to the results of machining tests. The relationship between the thickness of the surface layer and residual stress at the surface due to coating has been evaluated. Though the tool life of coated ceramics is shorter than that of cubic boron nitride, tool edge preparation by coating contributes to the reduction in machining costs due to the application of higher cutting speeds.     

基于公共通信网络的刀具磨损监控系统研究

采用声发射和功率测定的多状态测量法,采集多种刀具状态信息,利用目前的公共移动通信网络(GPRS/GSM),对刀具在线监控远程数据进行传输,建立了刀具磨损监控系统的总体方案,并对系统的软硬件进行设计,开发了刀具磨损监控系统。     

Effects of cutting angle,edge preparation,and nano-structured coating on milling performance of a gamma titanium aluminide

Gamma titanium aluminides are intermetallic alloys. Recently, they have been evaluated as important contenders for structural applications in the automotive and aerospace sectors. This is due to their excellent high-temperature performances and their significantly lower density compared to nickel-based superalloys. In this paper, an analysis of machinability of a gamma TiAl obtained via an electron beam melting (EBM) process is presented. The effects of tool geometry modifications, in terms of cutting tool angles and cutting edge preparation, were investigated. The reduction of radial rake angle and the drag finishing process for cutting edge preparation resulted in an increase of the tool life of the carbide end mills. Nanogradient tool coatings were also observed to affect tool wear during milling tests, and the results highlight that AlSiTiN coating performs better compared to CrAlSiN coating. A post-coating polishing treatment was also taken into account, and it allowed a further reduction of tool wear. The overall results indicate that the machinability of this difficult-to-cut material can be significantly improved by an adjustment of the cutting edge geometry, and by using an AlSiTiN coating system.     

VB环境下刀具数据库管理系统的开发

随着现代数控技术的不断发展和普遍应用,刀具数据库的开发与管理有了极其重要的意义和实际的研究价值.本文在VB环境下,利用开放式数据库互联(ODBC),通过数据库关联和程序设计完成了具有较高适应性的刀具数据库管理系统.通过链接、访问及维护刀具数据库,可有效加强对刀具的管理及合理利用.     

刀具自动补偿系统的改造

FANUC-POWER MATE-H 系统是性能可靠、控制灵活、具有多轴伺服控制功能的数控系统,是当今世界尤其是亚洲国家广泛使用的数控系统.本文介绍了利用两套FANUC数控系统连杆半精镗-精镗自动线L678刀具补偿数控系统进行改造的过程及其应用效果,并根据刀具磨损线性化补偿对提高加工工件的CP值进行了讨论.     

基于3D打印技术的模具制造

本文以某限位块模具型芯为例,利用生产浪费最小、能量消耗最低、污染排放最小的3D打印技术理念生产制造,打破了传统的模具设计与制造方法,从而可以实现绿色模具和快速模具制造。     

Application of statistical filtering for optical detection of tool wear

The application of automated tool condition monitoring systems is very important for unmanned machining systems. Tool wear monitoring is a key factor for optimization of the cutting processes. Basically, tool wear monitoring systems can be subdivided into two classes: direct and indirect. Currently direct tool wear monitoring systems are most frequently based on machine vision by camera. Several approaches have been studied for tool wear detection by means of tool images, and an innovative statistical filter proved to be very efficient for worn area detection. A new approach has been implemented and tested in order to develop an automatic system for tool wear measurement. This new approach is described in this paper and the main topics related to tool wear monitoring using wear images have been discussed.     

Sensorless tool failure monitoring system for drilling machines

It is well known that on-line tool condition monitoring has great significance in modern manufacturing processes. In order to prevent possible damages to the workpiece or the machine tool, reliable techniques are required providing an on-line response to an unexpected tool failure. Drilling is one of the most fundamental machining operations and two of the most crucial issues related to it are tool wear and fracture. During the spindle process, the motor driver current is related to the drill condition: power consumption is higher for a worn drill in comparison to a sharp drill for the same process. This difference in power consumption can be self-correlated to obtain the resulting waveform variance to provide a merit figure for tool condition. This paper describes a driver current signal analysis to estimate the tool condition by using the discrete Wavelet Transform in order to extract the information from the original cutting force, and through an autocorrelation algorithm evaluate the tool wear in the form of an asymmetry weighting function. The current is monitored from the motor driver to give a sensorless approach. Experimental results are presented to show the algorithm performance, a complete sensorless tool failure system which allows the detection of tool failure as a function of spindle current in real time.     

基于改进CC路径截面线法的机器人铣削加工刀具轨迹生成方法

机器人铣削加工技术是当前机器人技术发展的重要方向之一,而刀具轨迹的自动生成是实现机器人铣削加工的一个关键环节。以Open Cascade为几何造型技术开发平台,以改进的CC路径截面线法为轨迹生成方法,通过对约束面间距进行动态调整,改进了传统CC路径截面线法刀轨疏密不一致的问题,从而能够提高机器人铣削加工精度。在此基础上,开发出相应的CAD/CAM软件系统,实现了自由曲面精粗加工刀具轨迹的自动生成。最后,通过仿真和实验对生成的刀具轨迹进行了验证,验证了方法的可行性和准确性。     

Cutting edge geometries

Tool life and performance are decisively determined by cutting edge geometry. An appropriate shape of the cutting edge improves wear resistance, tool life and process reliability. This paper reviews major developments in cutting edge preparation technologies and methods of cutting edge characterization. Moreover, the influences of cutting edge geometry on chip formation, material flow, as well as mechanical and thermal loads on the tool are discussed. The essential modeling and simulation approaches are presented. Effects on surface integrity are described. Finally, an overview of important perceptions for prospective research and development in this field is provided.