共查询到20条相似文献,搜索用时 46 毫秒
1.
硬质合金刀具高速车铣和铣削TC4钛合金磨损试验对比 总被引:1,自引:0,他引:1
采用H13A未涂层硬质合金刀具对TC4钛合金进行高速正交车铣和铣削试验,并从刀具磨损破损形态、磨损机理及其寿命等方面进行对比分析。研究表明:高速正交车铣和铣削钛合金时,前、后刀面主要以粘结磨损为主,车铣加工时在切削刃口易形成积屑瘤及连续切屑,但对刀具材料粘结较轻;高速铣削时,对刀具材料粘接较重,在前刀面刃口附近形成凹坑及崩刃;后刀面最大磨损的位置不相同。试验对比了相同切削条件时刀具使用寿命,结果表明采用正交车铣加工可以获得更长的刀具使用寿命。 相似文献
2.
Jinting Xu Hai Zhang Yuwen Sun 《The International Journal of Advanced Manufacturing Technology》2018,98(1-4):107-118
The parts, in automotive, aerospace, die/mold industry, which have extremely high demands on the quality and integrity of the surface, are usually milled by CNC machine tools. In order to obtain the desirable surface quality, it is an effective way to choose the appropriate cutting parameters before machining by simulating the surface topography formed in the milling process. To do so, this paper develops a model based on the swept surface of the cutting edge and N-buffer model for predicting the surface topography and studies the effect of various cutting parameters. In this developed model, the mathematical equation of the cutting edge is first given, and then based on the relative motion between the cutter and the workpiece, the swept surface of the cutting edge along the tool path is accurately analyzed and modeled from the perspective of kinematics, which is used to describe realistically the cutting interaction between the cutter and the workpiece. Subsequently, the milling process is simulated by an improved N-buffer model by means of the proposed accurate interpolation method for calculating the cusp height. This procedure presents the advantage of not requiring any numerical iteration or approximation to gain the cusp height of any point on workpiece. On basis of the model, the effect of the cutting parameters such as spindle speed, feedrate, inclination angle, path interval, and cutter runout is investigated. Finally, the real machining experiments are performed and compared with the predicted results. The simulated surface topography shows a good agreement with the experimental one. This demonstrates that the developed model can predict accurately the surface topography and also provide the great potential for the surface quality control and the cutting parameter selection in actual production. 相似文献
3.
无偏心正交车铣理论切削力 总被引:4,自引:1,他引:3
为了深入研究无偏心正交车铣加工的切削过程,针对无偏心正交车铣加工变厚度、变深度切削的特点,把切削刃划分为圆周刃和端面刃两部分,分别以其瞬时切削面积为主要研究对象构建了计算各自瞬时切削力的数学模型,并通过数学模型对其瞬时切削力的变化进行了仿真。结果表明,无偏心正交车铣为多参数影响下的变切削力加工,圆周刃、端面刃在切削过程中都发挥重要作用,瞬时切削力的最大值由二者共同决定,但圆周刃上的切削力明显大于端面刃。圆周刃、端面刃几乎同时切入、切出工件,在一次完整的切削过程中圆周刃上的瞬时切削力发生一次突变,端面刃上的瞬时切削力则无突变发生。 相似文献
4.
正交车铣高强度钢的刀具耐用度及磨损机理研究 总被引:2,自引:0,他引:2
通过TiN涂层硬质合金端铣刀正交车铣58SiMn高强度钢的刀具磨损试验,建立了刀具耐用度T-(vc,fa,fz)关系泰勒公式,分析了各切削用量对刀具耐用度的影响关系;对正交车铣刀具的磨损研究表明刀具表面材料的疲劳—剥落和切削刃微崩以及在高温下刀具材料中的元素与周围介质发生的化学反应磨损等是造成刀具磨损的主要原因。 相似文献
5.
K. V. R. Subrahmanyam Wong Yoke San Hong Geok Soon Huang Sheng 《The International Journal of Advanced Manufacturing Technology》2010,48(1-4):23-32
Ball nose milling of complex surfaces is common in the die/mould and aerospace industries. A significant influential factor in complex surface machining by ball nose milling for part accuracy and tool life is the cutting force. There has been little research on cutting force model for ball nose milling on inclined planes. Using such a model ,and by considering the inclination of the tangential plane at the point of contact of the ball nose model, it is possible to predict the cutting force at the particular cutting contact point of the ball nose cutter on a sculptured surface. Hence, this paper presents a cutting force model for ball nose milling on inclined planes for given cutting conditions assuming a fresh or sharp cutter. The development of the cutting force model involves the determination of two associated coefficients: cutting and edge coefficients for a given tool and workpiece combination. A method is proposed for the determination of the coefficients using the inclined plane milling data. The geometry for chip thickness is considered based on inclined surface machining with overlapping of previous pass. The average and maximum cutting forces are considered. These two forces have been observed to be more dominating force-based parameters or features with high correlation with tool wear. The developed cutting force model is verified for various cutting conditions. 相似文献
6.
7.
高速轴向车铣45钢刀具磨损的研究 总被引:1,自引:0,他引:1
介绍了轴向车铣加工的特点,通过试验得到了高速轴向车铣加工45钢时刀具的磨损曲线,分析了在水冷和干切削时TiN涂层和金属陶瓷刀具的磨损特点,得出采用干切削更有利于延长刀具使用寿命,且TiN涂层刀具比金属陶瓷刀具更适合高速轴向车铣加工45钢. 相似文献
8.
基于数控铣削加工仿真系统,研究了在虚拟制造环境下对球头铣刀磨损引起的曲面加工误差的预测与补偿。建立了与加工参数相关的球头铣刀磨损模型,用于预测球头铣刀切削刃的磨损量,提出了球头铣刀铣削加工误差的补偿方法,并通过实验验证了该方法的有效性。 相似文献
9.
Owing to heavy dynamic and thermal loads, PCBN tools are seriously worn during hard cutting, which largely constrains the improvement of their machining performance. Therein, the chamfered structure of a cutting edge has a notable influence on the tool wear. Thus, a comparative study was carried out on the wear morphology and wear mechanism of PCBN tools with either a variable chamfered edge or an invariable chamfered edge. The results indicate that, for a PCBN tool with a variable chamfered edge, the rake wear area is far from the cutting edge and slowly extends toward it. A shallow large-area crater wear occurs on the rake face, and the flank wear area has a long triangular shape with a smaller wear area and width, and the cutting edge remains in a good state during the cutting process. In contrast, for a PCBN tool with an invariable chamfered edge, a deep small-area crater appears on the rake face,and the wear area is close to the cutting edge and quickly extends toward it. Thus, it is easy for chips to accumulate in the crater, resulting in large-area and high-speed wear on the flank face. In addition, the tool shows a weak wear resistance. In the initial wear stage, the rake wear mechanism of the two cutting tools is a mixture of abrasive, oxidation, and other types of wear, whereas their flank wear mechanism is dominated by abrasive wear. With an aggravation of the tool wear, the oxidation and di usion wear mechanism are both increasingly strengthened. The rake wear of the cutter with a variable chamfered edge showed an obvious increase in the oxidation and di usion wear, as did the flank wear of the cutter with an invariable chamfered edge. This study revealed the wear mechanism of the PCBN tool with a variable chamfered edge and provided theoretical and technological support for its popularization and application in the machining of high-hardness materials. 相似文献
10.
在车铣复合加工中心上,进行了车铣加工高强度钢工件材料的刀具磨损强度实验,分析了车铣切削用量对刀具磨损强度的影响.研究表明,在影响车铣刀具磨损的切削用量中,切削速度对车铣刀具的磨损强度影响最大.并以车铣刀具的磨损实验为基础,以切削速度为变量,建立了车铣高强度钢的刀具磨损强度分析模型. 相似文献
11.
12.
轴向车铣等距型面的运动建模 总被引:4,自引:0,他引:4
为研究轴向车铣加工等距型面的切削过程,针对其运动过程复杂的特点,以矢量为研究对象,通过矢量分析建立描述其运动过程的数学模型,并给出基本矢量方程。通过数学模型对加工的运动轨迹进行仿真,分析主要切削参数对运动轨迹的影响。为验证运动矢量模型的正确性,进行等距型面的轴向车铣加工试验,得到包含内外轮廓等距型面的加工样件。结果表明,采用轴向车铣完全可以实现等距型面的内外轮廓加工,理论上只要增大铣刀与工件的转速比就可以得到足够小的工件表面粗糙度,且选用逆铣的切削方式更容易得到光滑的加工表面。 相似文献
13.
Ching-Ben Chen 《The International Journal of Advanced Manufacturing Technology》2007,35(5-6):493-504
Defining the helical angle as the angle between the cutting edge and revolving axis of the cutter presents the designing models
of the cutting edge and helical groove of a toroid shaped taper cutter. Under the condition of a certain revolving speed,
the relative radial and axial feeding speeds of the grinding wheel in two-axis NC machining of the cutter are deduced. The
models for calculating the actual obtained groove and the simulation-method of computer are also provided.The surface near
to the top of the end cutter has no helical cutting edges and infinite feeding speeds of NC machine. It is necessary to adopt
a supplementary cutting edge. A supplementary cutting edge is designed as a cutting edge with a constant pitch. This paper
provides valuable reference for the design and NC machining of this kind of toroid shaped taper cutter. 相似文献
14.
正交车铣工件表面形成机理的研究 总被引:6,自引:0,他引:6
通过数学方法对正交车铣已加工表面的形成机理进行了详细的理论研究,给出了已加工工件理论微观圆度的计算方法和侧母线的数学表达式,由此分析了主要切削参数对理论微观圆度和工件侧母线形成的影响,并对加工圆柱表面时偏心量和轴向进给量的取值范围进行了详细阐述。 相似文献
15.
16.
17.
18.
19.
A theoretical cutting force model for helical end milling with cutter runout is developed using a predictive machining theory, which predicts cutting forces from the input data of workpiece material properties, tool geometry and cutting conditions. In the model, a helical end milling cutter is discretized into a number of slices along the cutter axis to account for the helix angle effect. The cutting action for a tooth segment in the first slice is modelled as oblique cutting with end cutting edge effect and tool nose radius effect, whereas the cutting actions of other slices are modelled as oblique cutting without end cutting edge effect and tool nose radius effect. The influence of cutter runout on chip load is considered based on the true tooth trajectories. The total cutting force is the sum of the forces at all the cutting slices of the cutter. The model is verified with experimental milling tests. 相似文献
20.
瞬时刚性切削力的建模是铣削加工物理仿真的基础,然而,球头铣刀的刀齿形状复杂,加工过程中姿态多变,瞬时刚性铣削力的建模难度较大。在考虑刀具姿态调整的情况下,通过齐次坐标变换建立了刀齿的运动轨迹,提出了一种识别刀具和工件瞬时接触区的改进Z-MAP算法,通过计算当前刀齿的参考线与工件的边界面或刀齿扫掠面的交点求出瞬时未变形切屑厚度,并采用非线性回归的方法辨识了切削力系数,在此基础上使用微元积分法建立了瞬时切削力的计算模型。为了验证仿真模型的可靠性,分别进行了垂直加工和倾斜加工试验,试验和仿真结果具有较高的一致性,表明该建模仿真方法是有效的,可以为实际加工中参数的选择和优化提供理论依据。 相似文献