适于精扩孔加工的麻花钻的刃磨改进

介绍了麻花钻的特点、刃磨要领和使用.该钻头扩出的孔具有较好的表面粗糙度,又有较高的孔径精度,在加工过程中能够达到十分理想的效果.     

轧制高速钢直柄麻花钻的真空淬火加热

鉴于与盐浴淬火加热相比,真空淬火加热具有不污染环境、工件无氧化、无脱碳、畸变小等优点,对轧制的W6Mo5Cr4V2高速钢直柄麻花钻进行了真空淬火加热试验。结果表明,钻头的显微组织、硬度和红硬性与盐浴淬火加热的钻头相当,但切削性能因贫碳而稍差。提出了防止钻头在真空加热时贫碳、脱碳等的改进措施。     

PCD、PCBN超硬材料的加工特点及其刀具刃磨技术

本文简要介绍了PCD、PCBN材料的加工特点，进而说明了PCD、PCBN切削刀具的制造工艺及其对工装要求，最后重点阐述了PCD、PCBN刀具刃磨技术。     

麻花钻的改进

文章在分析普通麻花钻存在问题的基础上,讨论了麻花钻在材料选择、表面处理、结构设计和刀磨等方面的改进措施,重点讨论了三平面钻头和4刃钻的结构特点     

用于高效强力钻削的麻花钻

本文在简单回顾麻花钻的发展史的基础上,指出了普通麻花钻在钻削加工方面存在的缺点,如能耗大,钻头易横向滑移,使钻孔中心偏离既定位置,以及排屑困难等。文章就此介绍了几种常用的改进方案和倪志福的“群钻”以及日本人在后来所创造的具有螺旋式切削刃即所谓“S”型钻刃的钻头。最后就国外几个著名的钻头制造厂所生产的新型钻头介绍了其结构特点。     

和田青玉超声波深孔高速钢麻花钻钻削试验研究

基于和田玉特殊的物理性能,采用直径为2、1.5、1 mm的高速钢麻花钻,在其主轴转速为700、1500、1800r/min;进给量为3μm/r和5μm/r的情况下;分别进行附加超声波振动和不附加超声波振动加工试验;在钻削加工过程刀具磨损,扩孔量、孔内表面粗糙度三个方面进行对比分析,超声振动波钻削能获得更好的加工质量和效率,并能减少钻头的磨损和破坏,为和田玉精密加工提供了一种新的深孔加工工艺方法。     

刃磨时用限位套提高模具寿命

<正> 1 问题的提出 图1所示是分马力异步电机的定、转子冲片和轴孔废料。为提高生产效率,采用复合模一次冲出。由于转子冲片和轴孔废料的面积较小,在模具的相应位置无法安装足够的橡皮或弹簧,因此在模具中须增设弹顶器和推件器。在带推件器模具的传统结构中,凹模或凸凹模的刃口使用高度常不足总高度的一半,因而模具使用寿命较低。     

刃磨时残余应力对硬质合金强度特性的影响

研究了在金刚石刃磨和电金刚石刃磨时硬质合金刀片上引起的残余应力 ,及其对硬质合金强度的影响     

钛合金深孔刀具耐用度及参数优化

深孔钻削钛合金难度大,刀具极易损坏。本文在原来自行设计和制造的内排屑钻孔（BTA）深孔钻头基础上．通过对钛合金材料的深孔加工试验,对改进后的深孔钻头的失效机理进行了分析研究,并探讨了钛合金深孔加工时进给量、刀具转速与耐用度的关系,优化了工艺参数和刀具结构、最终达到提高刀具耐用度的目的。     

用运动合成法实现钻尖的刃磨

将运动合成法用于钻尖刃磨的研究,在分析运动合成机理的过程中,建立了钻尖的位姿方程,应用运动插补实现钻尖的刃磨.该方法提高了钻尖刃磨的自动化程度,保证了刃磨质量.     

高速钢刀具磷化处理试验研究

为了探索磷化处理对高速钢刀具寿命的影响情况,采用不同工艺规范的磷酸锌盐快速热磷化和马日夫盐热磷化处理刀具,通过比较经磷化处理的刀具与未磷化处理的刀具的切削情况和耐蚀性能,得知磷化处理可以提高金属切削刀具的寿命和抗腐蚀性能.介绍了磷化膜质量检验的方法,重点分析了磷化处理工艺过程中,零件表面粗糙度、钢的合金元素、显微结构、磷化液温度、酸度、磷化时间等因素对磷化处理的影响.通过对磷化处理提高刀具寿命和抗蚀性能的机理分析,得到磷化处理提高刀具寿命和抗蚀性能的原因是:磷化膜导热性能差,不易使刀具切削刃升温,同时磷化膜改善了刀具表面的润滑条件.     

Modeling of tool wear in drilling by statistical analysis and artificial neural network

The useful life of a cutting tool and its operating conditions largely control the economics of the machining operations. Hence, it is imperative that the condition of the cutting tool, particularly some indication as to when it requires changing, to be monitored. The drilling operation is frequently used as a preliminary step for many operations like boring, reaming and tapping, however, the operation itself is complex and demanding.

Back propagation neural networks were used for detection of drill wear. The neural network consisted of three layers input, hidden and output. Drill size, feed, spindle speed, torque, machining time and thrust force are given as inputs to the ANN and the flank wear was estimated. Drilling experiments with 8 mm drill size were performed by changing the cutting speed and feed at two different levels. The number of neurons in the hidden layer were selected from 1, 2, 3, …, 20. The learning rate was selected as 0.01 and no smoothing factor was used. The estimated values of tool wear were obtained by statistical analysis and by various neural network structures. Comparative analysis has been done between statistical analysis, neural network structures and the actual values of tool wear obtained by experimentation.     

高速切削刀具系统

根据高速切削对刀具系统的要求,分析了高速回转刀具的结构特点以及常规7：24锥度刀柄结构存在的不足,介绍了国外对7：24锥度刀柄的多种改进型设计和替代性设计方案,分析了各种设计方案的优缺点。     

高速磨床的变频调速

本文简介了变频器在高速磨床上的应用及逆变器的软、硬件设计。     

基于球面线性插值的机器人磨削工具姿态规划

在机器人磨削去除汽车轮毂翻边及毛刺中,为解决传统方法所规划的工具姿态灵活度不够、平稳性差等问题,提出一种基于球面线性插值的机器人磨削工具姿态规划方法。将离散磨削路径拟合为B样条曲线,通过对样条路径曲率信息的提取,实现轮毂磨削关键区域的识别;在关键区域的关键点处设定磨削工具姿态,并利用关键工具姿态间的球面线性插值,生成沿路径光顺变化的工具姿态;通过Z向浮动对磨削中的工具位置进行微调,以提高磨削的均匀性、减少工具的磨损。结果表明：所提方法可使机器人磨削工具姿态角度波动比优化前降低22.28%,角速度波动降低40.43%,从而能够有效提升磨削的平稳性。     

Chatter Stability of Metal Cutting and Grinding

This paper reviews fundamental modeling of chatter vibrations in metal cutting and grinding processes. The avoidance of chatter vibrations in industry is also presented. The fundamentals of orthogonal chatter stability law and lobes are reviewed for single point machining operations where the process is one dimensional and time invariant. The application of orthogonal stability to turning and boring operations is presented while discussing the process nonlinearities that make the solution difficult in frequency domain. Modeling of drilling vibrations is discussed. The dynamic modeling and chatter stability of milling is presented. Various stability models are compared against experimentally validated time domain simulation model results. The dynamic time domain model of transverse and plunge grinding operations is presented with experimental results. Off-line and real-time chatter suppression techniques are summarized along with their practical applications and limitations in industry. The paper presents a series of research topics, which have yet to be studied for effective use of chatter prediction and suppression techniques in industry.