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11.
对学院使用的大型精密机械设备——五轴加工中心和数控铣床等设备的安装条件、验收指标、技术管理和日常维护进行了阐述,确保设备到位后及时安装和有效使用。 相似文献
12.
13.
Zhiqiang Li Wuyi Chen 《International Journal of Machine Tools and Manufacture》2006,46(12-13):1428-1434
Traditional cutter positioning methods have defects of global errors and incomplete optimization. Because of using local differential geometry and focusing on the cutting contact point, these defects cannot be avoided and will deteriorate accuracy in precision machining. The authors presented the conception of actual cutting edge of a toroidal mill which was extended from cutting contact point, and pointed out its importance in programming. Instantaneous cutter position error (ICPE) was also investigated. A new global method based on the ICPE curve was presented. Taking the relationship between surface and cutter into consideration thoroughly, this global method shows many advantages which have been verified by simulation and cutting tests. 相似文献
14.
模具生产联合体是由小规模企业组成的模具设计、制造联盟,由于设备、工装和人员分属于不同的加盟企业,其作业排序过程非常复杂。为此提出一种复合式模具生产联合体的生产排序方法:依据基本优先规则首先完成单一工序作业,然后对多工序作业用改进遗传算法进行工艺优化,求出最优解和次优解,再使用评价函数法选择最佳作业路线。该方法在生产试验中取得了良好的成效.能较好满足模具用户和加盟企业两方面的需要。 相似文献
15.
G. Pantazopoulos 《Journal of Materials Engineering and Performance》2002,11(4):402-407
C 38500 is a widely used copper alloy with a great variety of applications from decoration and architecture to mechanical/electrical
engineering. The chemical composition of this alloy offers superior machinability and subsequently increased productivity
in high-speed machining and manufacturing processes. In European countries, this alloy is used primarily as free cutting brass
(CW 614N according to EN 12164: 1998), similar to C 36000 alloy, which is used also for thread rolling. The lower percentage
of Cu compared to C 36000 (nominal 58% instead of 61%) decreases the cost of the raw materials. This paper reports the principal
aspects of microstructure, mechanical properties, and machinability of this alloy in relation to the industrial manufacturing
process used. 相似文献
16.
The originality of this work consists in taking photographs of chips during the cutting process for a large range of speeds. Contrary to methods usually used such as the quick stop in which root chips are analyzed after an abrupt interruption of the cutting, the proposed process photographs the chip geometry during its elaboration. An original device reproducing perfectly orthogonal cutting conditions is used because it allows a good accessibility to the zone of machining and reduces considerably the vibrations found in conventional machining tests. A large range of cutting velocities is investigated (from 17 to 60 m/s) for a middle hard steel (French Standards XC18). The experimental measures of the root chip geometry, more specifically the tool-chip contact length and the shear angle, are obtained from an analysis of the pictures obtained with a numerical high-speed camera. These geometrical characteristics of chips are studied for various cutting speeds, at the three rake angles −5, 0, +5° and for different depths of cut reaching 0.65 mm. 相似文献
17.
ABSTRACTWhile selective laser melting (SLM) offers design freedom of metal parts with much less material consumption, there exist several limitations, including high surface roughness, low-dimensional accuracy, and high tensile residual stresses. To make functional parts with high form accuracy and superior surface integrity, an as-SLM part needs finishing to remove the deposited surface material. The integration of machining and SLM creates a hybrid manufacturing route to overcome the inherited limitations of SLM. However, little study has been done to characterise surface integrity of an as-SLM part followed by machining (e.g. hybrid SLM-milling). In this paper, surface, integrity including surface roughness, microstructure, and microhardness, have been characterised for IN718 samples processed by the hybrid process. It has been found that microhardness varies with the scan direction and the use of coolant in the subsequent milling, and surface integrity can be significantly improved by the hybrid SLM-milling route. 相似文献
18.
三角片离散法实现数控铣床加工仿真 总被引:14,自引:3,他引:11
罗堃 《计算机辅助设计与图形学学报》2001,13(11):1024-1028
三角片离散法是根据三轴数控铣床加工中的特点提出的加工仿真方法。文中结合笔者在微机上制作仿真软件的经验,使用三角片离散法实现数控铣床加工仿真;并详细地介绍了三角片离散法的原理、简化模型、计算方法以及提高效率的途径。该方法简单易行,而且有很好的真实感效果。 相似文献
19.
论述了三弧段型面曲线的形成及其曲线参数方程,编制了三弧段型面的数控加工宏程序,适用于各种不同参数的三弧段型面的加工,且能够满足加工精度的要求。 相似文献
20.
YingTang YoshiakiKakino 《北京科技大学学报(英文版)》2005,12(2):187-191
The trend in die/mold manufacturing at present is towards the hard machining at high speed to replace the electron discharge machining. Failure forms of the A1TiN-coated micro-grain carbide endmill when used for the machining of/IS SKD61 (HRC 53), a widely used material in die/mold manufacturing, are investigated. The endmill shows a characteristic that tool life decreases greatly due to the chipping when overload occurs or the rapid increase of wear when over-heat accumulation in cutting edges. As a consequence of the investigation, a strategy to regulate heat generation in the end milling process is proposed. This is accomplished by controlling the cutting arc length, i.e. the length of each flute engaging workpiece in a cutting cycle. Case studies on the slot end milling and comer rounding are conducted. The results show that the proposed strategy suggests the optimal tool path as well as the optimal pitch between successive tool paths under the cutting time criterion. 相似文献