高速干切削加工的刀具技术及其应用

在分析高速干切削加工特点的基础上,根据绿色切削工艺过程的具体要求,讨论了高速干切削加工不同材质时,刀具材料、刀具涂层以及刀具结构的优化等方面关键技术及其应用.     

干式切削加工中刀具的选择

在分析干切削加工特点的基础上，提出了干切削加工对刀具的具体要求，讨论了干切削加工中刀具的选择原则。     

干切削刀具的设计理论研究

在分析干切削加工特点的基础上,提出了干切削加工对刀具的要求,并对国内外干切削加工刀具的研究进展作了综合归纳与评述,阐明了各种方式的优缺点,指出了干切削加工刀具研究中的值得重视的发展方向。     

21世纪初我国切削加工与刀具技术展望

切削加工与刀具在21世纪初仍将是制造技术的基础工艺和主要工艺装备,并将在开发新的加工工艺、革新传统工艺上发挥新的作用。高速切削、硬切削、干切削工艺将进入实用阶段。硬质合金刀具、超硬刀具、涂层刀具将成为切削刀具的主体,在今后10～15年内整体切削效率可提高1～2倍。刀具技术发展的主流是:进一步提高精度、效率和可靠性,安全和环保亦将成为重要课题,数量的增长将退居次要位置。激光切削或激光辅助切削等新的加工方法将得到开发。工具行业将更新观念,面向加工技术,为用户提高加工效率、降低成本提供成套切削技术。     

干切削的关键技术

对干切削或准干切削的关键技术所涉及的刀具、机床、加工工艺及其它因素等几个方面进行了介绍。     

干切削加工刀具及其设计

适宜的刀具材料和刀具几何参数是干切削加工的关键条件之一.在分析干切削加工对刀具要求的基础上,阐述了干切削刀具设计的要点,并结合应用实例说明了刀具设计对干切削加工的重要性.     

干切削加工刀具

适宜的刀具材料和刀具几何参数是干切削加工的关键条件之一。本文在分析干切削加工对刀具要求的基础上,阐述了干切削刀具设计的要点。     

干切削加工的润滑刀具技术研究

在分析干切削加工特点的基础上,提出了实现干切削加工的重要途径-设计和开发润滑刀具,并总结了实现润滑刀具的方式、各自特点以及值得重视的发展方向,指出润滑刀具的应用对于提高切削加工生产率、降低生产成本、减少资源消耗、防止切削液污染环境等具有重要的意义.     

干切削加工刀具及其设计

适宜的刀具材料和刀具几何参数是干切削加工的关键条件之一。文章在分析干切削加工对刀具要求的基础上,阐述了干切削刀具设计的要点,并结合应用实例说明了刀具设计对干切削加工的重要性     

干切削加工刀具材料及涂层应用

干切削是一种洁净制造工艺技术。该文分析了干切削加工对刀具材料的要求，讨论了刀具材料的选择及涂层技术，指出适宜的刀具材料及刀具涂层是干切削成功应用的关键。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.