滚切刀具的发展及典型刀具结构

简述滚切刀具发展史 ,论述各个时期研究成果的主要优点 ,给出一些典型刀具结构 ,并分析刀具结构的特点。     

高速切削过程测温方法综述

切削温度与加工精度和刀具磨损密切相关,高速切削过程中切削温度随着材料,刀具,切削用量的选择不同而呈现出与普通切削过程不同的变化规律.本文归纳了高速切削当中切削温度的测定方法,并指出了各种方法的优缺点及适用性.     

高速切削中切削温度研究方法

切削热与切削温度的产生和影响是高速切削技术研究的重要内容。高速切削过程中的温度检测技术与研究方法是在传统切削速度加工相关技术基础上的发展与创新。归纳了高速切削中切削温度实验测定方法和数值计算方法,指出了各种方法的优缺点及适用性。     

切削加工中喷雾冷却技术的试验研究

根据喷雾冷却原理,设计了用于金属切削加工的喷雾冷却装置,确定了刀具几何角度,选择水做为冷却液.实验表明,与干切削相比,喷雾冷却时切削区温度可降低200℃;切削液用量为(0.3～0.5)L/h,且当切削条件调整到理想状态时,工件表面不会有冷却液残留;能够适用于普通的硬质合金刀具.     

An automatic system based on vibratory analysis for cutting tool wear monitoring

The aim of this work is to develop a new, simple to use and reliable automatic method for detection and monitoring wear on the cutting tool. To achieve this purpose, the vibratory signatures produced during a turning process were measured by using a three-axis accelerometer. Then, the mean power analysis was proposed to extract an indicator parameter from the vibratory responses, to be able to describe the state of the cutting tool over its lifespan. Finally, an automatic detector was proposed to evaluate and monitor tool wear in real time. This detector is efficient, simple to operate in an industrial environment and does not require any protracted computing time.     

Analysis of tool temperature fluctuation in interrupted cutting

A unidimensional model for temperature distribution in the tool during intermittent cutting is presented. The tool-chip interface heating is approximated by a periodic rectangular heat flux. The effects of cutting time ratio, frequency of temperature fluctuation and thermal diffusivity of the tool material on internal temperature distribution and on thermal stresses developed in the tool have been discussed. With increasing cutting frequency, the temperature gradient in the cutting zone increases, but with higher thermal diffusivity of the tool material, it diminishes. The magnitude of thermal stresses increases with increase in amplitude of temperature fluctuation     

数控循环切削中刀具定位起始点的确定

重点介绍G71、G90、M98/M99这类有循环加工功能的指令格式、通过各参数含义的说明、循环路线的讲解,来说明循环起点在上述指令的确定方法,正确定位,避免打刀及空运行,对提高加工效率有一定的帮助。     

Effects of the cutting feed, depth of cut, and workpiece (bore) diameter on the tool wear rate

Most published studies on metal cutting regard the cutting speed as having the greatest influence on tool wear and, thus, tool life, while other parameters and characteristics of the cutting process have not attracted as much attention in this respect. This is because of the existence of a number of contradicting results on the influence of the cutting feed, depth of cut, and workpiece (bore) diameter. The present paper discusses the origin of the aforementioned contradicting results. It argues that, when the optimal cutting temperature is considered, the influence of the aforementioned parameters on tool wear becomes clear and straightforward. The obtained results reveal the true influence of the cutting feed, diameter of the workpiece, and diameter of the hole being bored on the tool wear rate. It was also found that the depth of cut does not have a significant influence on the tool wear rate. The obtained results provide methodological help in the experimental assessment and proper reporting of the tool wear rates studied under different cutting conditions.     

Novel tool wear monitoring method in ultra-precision raster milling using cutting chips

Tool wear monitoring is a popular research topic in the field of ultra-precision machining. However, there appears to have been no research on the monitoring of tool wear in ultra-precision raster milling (UPRM) by using cutting chips. In the present research, monitoring tool wear was firstly conducted in UPRM by using cutting chips. During the cutting process, the fracture wear of the diamond tool is directly imprinted on the cutting chip surface as a group of ‘ridges’. Through inspection of the locations, cross-sectional shape of these ridges by a 3D scanning electron microscope, the virtual cutting edge of the diamond tool under fracture wear is built up. A mathematical model was established to predict the virtual cutting edge with two geometric elements: semi-circle and isosceles triangle used to approximate the cross-sectional shape of ridges. Since the theoretical prediction of cutting edge profile concurs with the inspected one, the proposed tool wear monitoring method is found to be effective.     

精密切削刀具磨损监控系统设计

设计了刀具磨损检测控制系统,采用EPF10K10TC144-4主控芯片、位移传感器,采用分布式算法编制了控制软件并进行了系统仿真。将数据输入到CNC系统,修改刀具参数,并在数控车床上进行了切削实验。对比研究结果表明,该系统避免了人工检测误差、机床频繁停机,减少了换刀次数和重新对刀引入的二次误差,延长了刀具有效使用时间,且加工效率、加工精度、产品合格率都有明显提高。     

纯钒车削刀具磨损表面形态及机理研究

对金刚石刀具、涂层刀具及硬质合金刀具车削纯钒时刀具磨损形态及其磨损机理进行观察和分析.结果表明,在所选取条件下,不同刀具材料对工件材料切削时表现出的刀具磨损形态主要为前刀面磨损、后刀面磨损、微崩刃、剥落和粘结等.刀具的前刀面主要是沿切屑流出方向的沟槽形月牙洼磨损,而后刀面以粘结磨损为主.CD10刀具和H10非涂层刀具具有较佳的切削性能,而H13A非涂层刀具和GC1025涂层刀具不适于纯钒车削.     

切削余量对多层复合轴承摩擦磨损性能的影响

主要研究了切削余量对涡旋式压缩机动静盘专用聚四氟乙烯多层复合轴承的微观结构与摩擦学性能的影响。研究结果表明,随着切削余量的增大,裸露的铜含量增多,润滑剂组份降低;随着切削余量的增大,PTFE多层复合材料的摩擦系数表现出逐渐增大的趋势,而磨损率呈现先降低后增大的趋势,并且当切削余量为0.05mm时,复合轴承具有最佳的耐磨性;为有效地提高轴承的装配间隙,防止轴承高速运动产生较大的振动,应将轴承内表面车削0.05mm后装配应用。     

数控铣削加工曲面时刀具轨迹的研究

数控铣削加工曲面过程中,刀具的运动轨迹是影响加工质量的一个重要因素.研究了数控铣削加工过程中刀具轨迹的生成,以及不同轨迹形式对加工质量有何影响等内容.     

高速切削加工刀具材料的性能分析及合理化选择

阐述各种高速切削加工刀具材料的性能,并分析其物理特性和化学特性以及不同的成分合成对机械加工性能的影响.通过比较,并考虑切削刀具材料与加工对象的力学性能、物理性能和化学性能的匹配情况,合理地选择高速切削加工刀具的材料.     

Experimental method to analyze the oil mist impingement over an insert used in MQL milling process

This paper proposes an original method to determine the oil mist impingement over an insert based on different machining configurations (rotation velocities) and different inner canalization designs, without material removal, on milling tool. The oil mist spray is determined using different holders as an insert. Glass plate and blotting paper are used and evaluated in this work to get as much information as possible, based on micro–macro scale observations. The imprint size of the oil mist spray distribution, the particle sizes and the fluid film formation have been studied to determine the effects of the different configurations on the oil mist impingement behavior. The droplet impingements and distributions on the glass plate are analyzed under a 3-D profilometer (microscopic scale). On the blotting paper, the distributions are analyzed with pictures of the oil marks (macroscopic scale). This original method gives quite fast particle distributions that can be used in industry. The different experimental results give large information about the oil mist behavior sprayed on the glass plate. Increasing rotation velocities increases the oil mist amount in the cutting area. Increasing the canalization orientation design gives a better focused spray. The rake angle has strictly no influence on the oil mist spray distribution. But sputtering effects have been highlighted and should be avoided to keep MQL efficiency.     

基于切削声音的刀具磨损状态识别研究

人工神经网络可以实现多特征信息的融合,将基于BP神经网络,建立各频率段能量百分比与刀具磨损的映射关系,进行刀具磨损状态识别的研究。最后在Labview环境下调用Matlab神经网络程序,初步实现了刀具磨损的识别。     

Minimal quantity lubrication in turning: Effect on tool wear

Industries and researchers are trying to reduce the use of coolant lubricant fluids in metal cutting to obtain safety, environmental and economical benefits. The aim of this research is to determine if the minimal quantity lubrication (MQL) technique in turning gives some advantages in terms of tool wear reduction. This paper reports the results obtained from turning tests and SEM analysis of tools, at two feed rates and two cutting lengths, using MQL on the rake and flank of the tool. The results obtained show that when MQL is applied to the tool rake, tool life is generally no different from dry conditions, but MQL applied to the tool flank can increase tool life.     

高速干式飞刀的切削温度模型

根据传热学和金属切削原理等,建立高速干式飞刀的切削温度模型,推导出多因素切削温度的计算公式,该模型的建立为进一步分析高速干式滚齿切削温度及切削机理奠定了基础。     

Effects of cutting fluid application on tool wear in machining: Interactions with tool-coatings and tool surface features

Minimal Quantity of Lubricant (MQL) application of cutting fluids (CFs), or near-dry machining, is being proposed as an environmentally and economically viable alternative to conventional flooding under conditions where dry cutting is not feasible. However, several issues related to CF application effects on cutting tool wear need further clarification, especially, the interactions of CF application with tool-coatings and chip-breakers, both of which are widely employed in industrial cutting tools, need further study. This paper presents the results of an experimental study into the effects of different CF application methods on tool wear during machining of AISI 1045 steel using flat-faced and grooved, coated carbide cutting tools. The results provide insight into the mechanisms of tool wear in the presence of CFs, as well as the influence of chip-breaking geometric features, and tool-coating systems, on CF action. The wear mode was observed to be dictated by thermal considerations, rather than by any friction reduction capability of different CF application methods, and forced attempts at achieving lubricating action were negatively affecting tool life under some conditions.     

The computer simulation of the temperature distribution on the surface of ceramic cutting tools

The temperature distributions on the surface of Si₃N₄ and Ti(CN) ceramic cutting tools for turning different metallic materials were calculated and plotted using computer simulation based on a mathematic model of heat sources. The results showed that the temperature on the rake face of the ceramic cutting tools for turning 18-8 stainless steel was much higher than that for turning 1045 plain carbon steel due to the much lower thermal conductivity of the former, the temperature increased with increasing cutting speed. This observation is important in explaining the wear resistance and wear mechanisms of the two ceramic cutting tools. The computed temperature distributions on the surface of the ceramic cutting tools were checked by measurement with a thermal video system (TVS), and showed good agreement.