数控铣削加工中刀具半径补偿问题研究

刀具半径补偿是数控铣削加工中的常用功能，就数控铣削加工中刀具半径补偿的建立和取消、刀具半径补偿量的指定和计算方法、刀具半径补偿功能的应用进行了研究。     

刀具半径补偿指令的正确使用方法和特点

刀具半径补偿指令是数控编程中经常用到的指令，本文就数控切削加工中刀具半径补偿的建立、进行和取消以及刀具半径补偿量的指定、计算方法和刀具半径补偿功能的应用等进行了介绍。     

矢量法刀具半径补偿原理

矢量法刀具半径补偿，具有程编简单（刀具半径补偿全由机器自动解决，完全与程编无关），刀具半径补偿时停刀时间短暂以及在对复杂曲线直接插补（如抛物线插补、椭圆插补等）时同样能有效地进行刀具半径补偿等优点。本文详细介绍矢量法刀具半径补偿的补偿原理，尖角过渡时的刀具自动转接，刀具趋近工件时的起始刀具矢量偏差倒正等的原理和实现方法。     

刀具半径补偿功能及常见过切现象的规避

刀具半径补偿是数控加工中一个常用的指令，合理使用刀具补偿功能在数控加工中有着非常重要的作用，就刀具半径补偿功能及在数控加工中进行刀具半径补偿时常见的过切现象进行了讨论。     

刀具半径补偿指令在数控编程中的应用

刀具半径补偿指令是数控编程中常用到的指令.就数控切削加工中刀具半径补偿的建立、进行和取消以及刀具半径补偿量的指定、计算方法和刀具半径补偿功能的应用等进行了介绍.     

刀具半径补偿指令的正确使用方法和特点

刀具半径补偿指令是数控编程中经常用到的指令,现她数控切削加工中刀具半径补偿的建立、进行和取消以及刀具半径补偿量的指定、计算方法和刀具半径补偿功能的应用等进行了介绍.     

刀具半径补偿在数控铣削中的应用研究

刀具半径补偿功能是数控机床的重要功能,在生产中,合理使用刀具补偿有着非常重要的意义。就刀具半径补偿的过程,刀具半径补偿在数控铣削中的应用,使用刀具半径补偿时应注意的问题进行阐述,以此来保证数控铣削加工的高效性和精确性。     

数控铣削加工中刀具半径补偿功能的正确使用

在数控铣削加工中，根据按零件轮廓编制的程序和预先设定的偏置参数，数控装置能实时自动生成刀具中心轨迹的功能称为刀具半径补偿功能；实现刀具半径补偿功能包括三个步骤：刀补的建立、刀补的进行、刀补的取消；在数控加工过程中，刀具半径补偿功能的正确使用。可以简化计算、提高编程的效率和加工精度。     

数控车床加工中刀具半径补偿的应用探究

刀具半径补偿一直以来是数控车床加工过程中非常关键的问题,首先就刀具半径补偿进行了简单的介绍,并对数控车床加工中刀具半径补偿的应用进行了研究分析。刀具半径补偿的介入对数控车床进行工件加工有明显的帮助,其运用明显提高了产品的加工精度和产品的生产效率,所以数控车床操作中掌握刀具半径补偿的应用非常关键,极具推广价值。     

数控车床加工中刀具补偿的应用

全面介绍了数控车床加工过程中的刀具补偿，并且对数控车床不具备刀具半径补偿功能时的刀具补偿计算方法进行了阐述。     

Study of the upper bound of tool edge radius in nanoscale ductile mode cutting of silicon wafer

In cutting of brittle materials, experimentally it was observed that there is an upper bound of tool cutting edge radius, beyond which, although the undeformed chip thickness is smaller than the tool cutting edge radius, the ductile mode cutting cannot be achieved. However, why there is an upper bound of tool cutting edge radius in nanoscale ductile mode cutting of brittle materials has not been fully understood. In this study, based on the tensile stress distribution and the characteristics of the distribution obtained from molecular dynamics simulation of nanoscale ductile cutting of silicon, an approximation for the tensile stress distribution was obtained. Using this tensile stress distribution with the principles of geometrical similarity and fracture mechanics, the critical conditions for the crack initiation have been determined. The result showed that there is a critical tool cutting edge radius, beyond which crack initiation can occur in the nanoscale cutting of silicon, and the chip formation mode is transferred from ductile to brittle. That is, this critical tool cutting edge radius is the upper bound of the tool cutting edge radius for ductile mode cutting of silicon.     

A study of the effect of tool cutting edge radius on ductile cutting of silicon wafers

Ductile mode cutting of silicon wafers can be achieved under certain cutting conditions and tool geometry. An experimental investigation of the critical undeformed chip thickness in relation to the tool cutting edge radius for the brittle-ductile transition of chip formation in cutting of silicon wafers is presented in this paper. Experimental tests for cutting of silicon wafers using diamond tools of different cutting edge radii for a range of undeformed chip thickness are conducted on an ultra-precision lathe. Both ductile and brittle mode of chip formation processes are observed in the cutting tests. The results indicate that ductile cutting of silicon can be achieved at certain values of the undeformed chip thickness, which depends on the tool cutting edge radius. It is found that in cutting of silicon wafers with a certain tool cutting edge radius there is a critical value of undeformed chip thickness beyond which the chip formation changes from ductile mode to brittle mode. The ductile-brittle transition of chip formation varies with the tool cutting edge radius. Within the range of cutting conditions in the present study, it has also been found that the larger the cutting edge radius, the larger the critical undeformed chip thickness for the ductile-brittle transition in the chip formation.     

钝圆刀刃切削的有限元模拟

利用商业有限元分析软件Marc对考虑切削刃钝圆半径的切削加工过程进行了有限元模拟。分析了切削刃钝圆半径在切削加工过程中对切削力和切削温度的影响     

NANOSCALE CUTTING OF MONOCRYSTALLINE SILICON USING MOLECULAR DYNAMICS SIMULATION

It has been found that the brittle material, monocrystalline silicon, can be machined in ductile mode in nanoscale cutting when the tool cutting edge radius is reduced to nanoscale and the undeformed chip thickness is smaller than the tool edge radius. In order to better understand the mechanism of ductile mode cutting of silicon, the molecular dynamics (MD) method is employed to simulate the nanoscale cutting of monocrystalline silicon. The simulated variation of the cutting forces with the tool cutting edge radius is compared with the cutting force results from experimental cutting tests and they show a good agreement. The results also indicate that there is silicon phase transformation from monocrystalline to amorphous in the chip formation zone that can be used to explain the cause of ductile mode cutting. Moreover, from the simulated stress results, the two necessary conditions of ductile mode cutting, the tool cutting edge radius are reduced to nanoscale and the undeformed chip thickness should be smaller than the tool cutting edge radius, have been explained.     

基于Deform 3D的刀具切削刃钝圆半径的优化设计

运用Deform 3D软件对考虑了刃口半径的切削过程进行了有限元仿真,分析了切削刃半径对加工过程对切削力和切削温度的影响。并对刀具应力及刀具磨损进行了分析,为刃口的优化设计提供了有力的依据。     

Cutting force model considering tool edge geometry for micro end milling process

The analysis of the cutting force in micro end milling plays an important role in characterizing the cutting process, as the tool wear and surface texture depend on the cutting forces. Because the depth of cut is larger than the tool edge radius in conventional cutting, the effect of the tool edge radius can be ignored. However, in micro cutting, this radius has an influence on the cutting mechanism. In this study, an analytical cutting force model for micro end milling is proposed for predicting the cutting forces. The cutting force model, which considers the edge radius of the micro end mill, is simulated. The validity is investigated through the newly developed tool dynamometer for the micro end milling process. The predicted cutting forces were consistent with the experimental results.     

A FINITE ELEMENT ANALYSIS OF BURR FORMATION IN FACE MILLING OF A CAST ALUMINUM ALLOY

The research discussed in this article focuses on the effects of tool geometry (i.e., rake angle and cutting edge radius) and flank wear upon burr formation in face milling of a cast aluminum alloy. As to tool edge preparation, the use of a tool with variable cutting edge radius was investigated using FEM, and compared for its cutting performance (i.e., burr reduction and tool life) with a conventional tool with uniform cutting edge radius. In order to evaluate 3D face milling through 2D orthogonal cutting simulations, the cross-sections that consist in the cutting speed direction and chip flow direction were selected at different locations along the tool rounded corner. At these cross-sections, the local value of cutting edge radius and their associated tool rake angles as well as the effective uncut chip thickness were determined for 2D cutting simulations. In addition, 3D face milling simulations were conducted to investigate more realistic chip flow and burr generation. Comparisons were made for burrs produced from 3D simulations with a sharp tool, 3D simulations with a worn tool and face milling experiments. Finally, recommendations for cutting tool design are made to reduce burr formation in face milling.     

ZK蜗杆过渡曲线的研究

建立了ZK蜗杆的数学模型 ,分析了加工ZK蜗杆时过渡曲线起始点随刀具半径的变化规律 ,首次提出了“最大刀具半径”的概念 ,给出了在不同蜗杆参数下“最大刀具半径”的数值。     

Modeling of the effect of tool edge radius on surface generation in elliptical vibration cutting

The elliptical vibration cutting (EVC) technique has been found to be a promising technique for ultraprecision machining of various materials. During the EVC process, two-dimension vibration movement of the cutting tool generates consecutively overlapping EVC cycles. In each cycle, the tool position relative to the workpiece gets continuously varied, and meanwhile, cusps are left along the nominal cutting direction. Such vibration marks, which have never been found in conventional cutting process, are considered to be a critical characteristic for the EVC technique. In order to analyze this unique characteristic, an analytical model based on geometrical relationships in the EVC process was developed to calculate the theoretical roughness, where the tool edge is assumed to be perfectly sharp. However, the effect of tool edge radius is probably significant, especially in the situation where the tool edge radius is comparable to the vibration amplitudes. Hence, in the present research, an analytical surface generation model for the EVC process is developed to better understand the surface generation process and predict the surface roughness. The tool edge radius is considered and investigated in detail in this new approach. Mathematical evaluation shows that the surface roughness value along the nominal cutting direction decreases with the increase of the edge radius. In order to validate the proposed model, a series of EVC grooving tests on soft and hard work materials were conducted using a polycrystalline diamond (PCD) tool by applying the ultrasonic EVC technique. The results show that the predicted roughness based on the proposed model correlates well with the experimental results measured by a white light interferometer, and the model considering the tool edge radius performs significantly better than the one without considering the edge radius in predicting the roughness along the nominal cutting direction.     

二维轮廓铣削刀具半径补偿算法的研究与实现

介绍了二维轮廓铣削加工条件下刀具半径补偿原理,对平面刀具半径补偿的各种转接类型进行了综合分析,提出了实现方法。以圆弧接圆弧为例给出了刀具半径补偿的算法,用VC6．0开发了刀具补偿算法程序,实现了二维轮廓刀具半径自动补偿功能。这种算法推导简单、运算速度快,能够满足CNC加工的需要。