淬硬钢的等离子弧加热切削研究

本文使用易于在生产现场实现的空气等离子加热装置对４５＃和９ＳｉＣｒ两种淬火钢进行等离子加热切削试验,对加热切削中切削力等进行研究,提出了天一定加热条件下的加的发削参数,以利于加热切削技术的推广应用。     

淬硬钢的等离子弧加热切削研究

本文使用易于在生产现场实现的空气等离子加热装置对４５＃和９ＳｉＣｒ两种淬火钢进行等离子加热切削试验，对加热切削中切削力、刀具磨损、加工表面质量等进行研究，提出了在一定加热条件下的加热切削参数，以利于加热切削技术的推广应用。     

用有限元法确定刀具几何角度

用有限元法确定刀具几何角度厦门鹭江大学（３６１００５）魏刚自从有限元分析法进入ＣＡＤ后，由于其独特的优越性，应用范围不断扩大，被公认为是一种有力的模拟工具，它能模拟物体在承受压力、温度和振动等外部环境作用时，其受力变形的大小和应力分布的状况；它的应用...     

涂层硬质合金刀具断续切削时的断裂

本文较全面而深入地研究了涂层硬质合金刀具断续切削时的断裂机理,可供从事这方面工作的人员参考。     

精密陶瓷的等离子加热切削

研究表明,加热工件材料的威氏硬度和表面弹性波速度没有变化。另外,用金相显微镜和扫描式电子显微镜观察组织的结果表明,没有发现加工变质层、加热变质层(结晶粒的粗大等)和显微裂纹     

等离子电弧加热切削加工工艺

等离子电弧加热切削工艺是有别于金属切削加工的新工艺,本文对其进行初步探讨。 1.加工方法 如图1所示,当工件旋转刀具进给切削时,在距切削刃适当距离的地方,利用高能等离子电弧把被加工工件切削区域瞬时加热,使其物理机械性能改变,这时刀具所切削的被加工区域,已不是坚硬的组织。因此,切削阻力大大降低,就可以增加切削用量,提高生产率。 显然,等离子电弧喷枪的运动应与刀具同步。 2.等离子体与等离子电弧 (1)气体电离 图2所示是带有较高电压的两极,在适当的间     

精密陶瓷的等离子加热切削

精密陶瓷硬度高,脆性大,在常温下是不能进行切削加工中的,因此,为了切削加工精密陶瓷,就必须要下一番工夫进行研究,作为解决的一种方法就是改变切削环境。     

导电加热切削时刀具的热电磨损

导电加热切削时,由于强烈的电热效应,刀具磨损形态与传统切削加工方法有所不同。本文研究了导电加热切削的电热特性和电物理现象,分析了导电加热切削时刀具的热电磨损及其机理。     

基于提高数控等离子切割件质量的研究

重点介绍国内数控等离子切割技术的现状和数控等离子切割出现的问题与控制措施。通过对割嘴高度、切割速度和工作气压对切割质量的影响与控制,切割热变形的影响与控制,切割系统抗干扰的影响与控制,数控切割软件的影响与控制等四个方面的探讨分析,可以有效避免数控等离子切割出现废品,提高了数控等离子切割件的质量。     

微量油膜附水滴切削性能的试验研究

通过对微量油膜附水滴切削液切削、干切削和乳化液切削进行对比试验,研究了微量油膜附水滴的切削性能。结果表明:微量油膜附水滴切削液能够显著提高切削性能;与干切削和乳化液润滑切削相比,采用微量油膜附水滴切削液能够降低切削力和加工表面的粗糙度值,延长刀具的使用寿命。     

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.     

硬脆材料切削加工负切削力现象的研究

以辉长岩为例,采用聚晶金刚石刀具进行硬脆材料切削加工试验,,在时域和频域内对切削力信号进行数字信号分析处理,提出硬脆材料切削力可分成切削趋势量和切削力随机量两部分;硬脆材料的组成结构特点和切削中刀具的振动是硬脆材料切削力出现负值现象的主要原因。     

二维图形轮廓线的夹角比较识别法

介绍了图形轮廓线的夹角比较识别算法。确定初始搜索点和初始搜索边，由初始的点和边开始查找出与之关联的边，计算各关联边在搜索方向的矢量，通过比较各边的矢量与参考矢量的夹角确定出轮廓边，重复上述过程直至轮廓边闭合为止。     

金属切削刀具的工作角度及其影响因素的研究

从刀具标注角度与工作角度的概念出发,较系统地分析影响金属切削刀具实际几何角度的主要因素,提出合理选择刀具几何角度的方法。对合理地设计、制造刀具,保证零件加工质量,提高加工效率,延长刀具寿命,降低生产成本具有重要意义。     

The effect of oil mist supply on cutting point temperature and tool wear in driven rotary cutting

We examined cutting point temperature and tool wear in driven rotary cutting. Cutting tests under dry and minimum-quantity-lubrication (MQL) conditions of stainless steel (SUS304) were carried out. Cutting point temperature was measured using a tool-work-thermocouple method at various cutting speeds. Cutting point temperature tends to increase with increased cutting speed. In driven rotary cutting, cutting point temperature was lower than that of non-rotation cutting. At high-speed cutting of 500 m/min, cutting point temperature was over 1200 °C in the non-rotation tool, but 1000 °C with driven rotary cutting. In addition, when driven rotary cutting was used with MQL, cutting point temperature was decreased to 900 °C. The magnitude of tool wear corresponded almost precisely to cutting point temperature. Severe adhesion on the rake face was observed and resulted in progressive wear on the rake face in rotary cutting at a cutting speed of 100 m/min. The appropriate cutting speed range passively shifts higher from the viewpoint of cutting temperature with rotary cutting.     

A study on ultra–high-speed cutting of aluminium alloy:: Formation of welded metal on the secondary cutting edge of the tool and its effects on the quality of finished surface

To investigate the mechanism of ultra–high-speed cutting for aluminium alloy, cutting experiments by using a machine tool equipped with an active magnetic bearing spindle were performed over a range of cutting speeds from 20 to 260 m/s. On the whole, the finished surface tends to improve with an increase in cutting speed. However, the formation of welded metal on the tool edge in the speed range from 100 to 200 m/s promotes the material side flow on the finished surface, which causes the surface roughness to increase.     

数控自动编程刀具轨迹生成及优化算法研究

对数控自动编程中所要生成的刀具轨迹算法进行优化研究,提出基于索引表的图元排序算法、封闭加工环的极线走向判断法和基于极值矩形和射线的综合封闭加工环的岛屿嵌套判断法;并研究刀具偏移和有效环判断算法,通过这些算法可以提高生成数控刀具轨迹的速度。     

Environmentally conscious hard turning of cemented carbide materials on the basis of micro-cutting in SEM (2nd report): stress turning with three kinds of cutting tools

Environmentally conscious hard turning and technology have placed increasing importance on the machining process. Cutting fluids have a significant impact on the environment, thus numerous research works are being performed to minimize their use. However, tool wear is very severe in hard turning cemented carbides without the use of cutting fluids. In this research, the effects of dry and wet cutting methods (vegetable oil mist and mineral oil) and tool material on cutting resistance and wear characteristics of cutting tools were experimentally investigated to study the possibility of creating an environmentally conscious hard turning of cemented carbides. Mist and wet cutting of the cemented carbides using poly-crystalline diamond (PCD) cutting tools were adopted to investigate how tool wear on the basis of micro-cutting in the Scanning Electron Microscope (SEM) can be reduced. Additionally, the poly-crystalline cubic boron nitride (PcBN) and the usual cBN cutting tools were compared with the PCD cutting tools. This paper was presented at the 9^th Asian International Conference on Fluid Machinery (AICFM9), Jeju, Korea, October 16–19, 2007.recommended for publication in revised form by Associate Editor Dae-Eun Kim HEO Sung Jung was born in Busan, R. O. K., in 1958. He received the Ph.D. in Mechanical Engineering from Osaka University, Osaka, Japan. He is a Full Professor of Mechanical Engineering at Doowon Technical College, Ansong -si, Gyonggi-do, Republic of Korea. His current research interests are in the areas of cutting of difficult-to-cut materials, environmentally conscious machining and cutting tool design.