共查询到20条相似文献,搜索用时 93 毫秒
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车轮对作为铁路运输车辆的主要承载部件,其制造加工中的车削环节一直是金属切削研究的重点内容.本文从车削过程中的刀具入手,对刀具的涂层、槽型方面进行分析.根据某两种型号的刀片在精车过程中的出现的磨损情况,通过调整车削进给量和车削速度,提高了加工精度,减少了刀具的磨损. 相似文献
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为解决细长轴车削加工弯曲变形量和表面粗糙度难以控制的质量问题,以及传统优化方法受刀具磨损影响导致加工质量可靠性差的弊端,以对称车削工艺为研究基础,基于细长轴车削过程弯曲变形和表面粗糙度形成机理分析,确定影响细长轴加工质量的关键因素;经试验分析、建立预测模型和多目标优化得出刀具未磨损条件下的最优车削参数;通过探究同一组车削参数条件下不同刀具磨损深度对加工结果的影响规律,提出基于刀具磨损深度的最优车削参数动态调整策略。经实际生产验证,最优车削参数动态调整策略不仅可以实现不同刀具磨损深度下弯曲变形量和表面粗糙度的精准控制,还可以提升生产效率、稳定生产节拍和降低生产成本。 相似文献
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对α+β钛合金TC11进行车削工艺研究,采用无涂层、PVD Ti Al N涂层、金刚石涂层三种刀片在干式加工和MQL冷却状态下进行车削试验。研究不同刀具、冷却方式和加工参数对车削TC11钛合金切削力、切削温度、加工表面质量、刀具寿命和刀具磨损方式等影响规律。通过相关试验数据得出相关切削参数,为优选加工刀具提供参考。 相似文献
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Inconel 718合金超声振动切削质量与刀具寿命控制研究 总被引:1,自引:1,他引:0
超声振动切削UVC是解决难加工材料精细加工问题的理想方法。在对Inconel718合金同时进行UVC和传统车削法CT加工中,研究了切削参数(切削速度、进给量、切削时间)对刀具切削性能的影响。通过对刀具磨损、切屑形态和工件表面粗糙度的研究,发现在进行低速硬态切削时,UVC在切削表面质量和刀具寿命方面均优于传统车削加工。同时随着刀具-工件表面接触率TWCR的降低,刀具磨损和切削力随之降低,而工件表面质量和刀具寿命得到提高。 相似文献
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研究了六种含有不同夹杂物曲轴钢的车削性能,开展了车削刀具磨损试验,并在线采集切削力,刀具后刀面磨损VB值和工件表面粗糙度每20min记录一次。通过扫描电镜和能谱仪对刀具磨损机理进行研究,同时用光学显微镜测量表面完整性。刀具磨损初期以磨粒磨损和涂层剥落为主;刀具进入稳定磨损阶段,出现崩刃和积屑瘤,崩刃引起的破损是刀具磨损加剧进而失效的主要原因。以氧化铝形式存在的铝夹杂物在车削中加剧了破损,使刀具寿命和表面完整性恶化。选用锰夹杂物作为固体润滑剂,延长了刀具寿命,提高了曲轴钢的切削性能。在曲轴钢的车削过程中,表面完整性与刀具磨损密切相关,刀具磨损越小,表面粗糙度越低,加工质量越好。 相似文献
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Yong Huang Y. Kevin Chou Steven Y. Liang 《The International Journal of Advanced Manufacturing Technology》2007,35(5-6):443-453
Direct machining steel parts at a hardened state, known as hard turning, offers a number of potential benefits over traditional
grinding in some applications. In addition, hard turning has several unique process characteristics, e.g., segmented chip
formation and microstructural alterations at the machined surfaces, fundamentally different from conventional turning. Hard
turning is, therefore, of a great interest to both the manufacturing industry and research community. Development of superhard
materials such as polycrystalline cubic boron nitride (known as CBN) has been a key to enabling hard turning technology. A
significant pool of CBN tool wear studies has been surveyed, in an attempt to achieve better processing and tooling applications,
and discussed from the tool wear pattern and mechanism perspectives. Although various tool wear mechanisms, or a combination
of several, coexist and dominate in CBN turning of hardened steels, it has been suggested that abrasion, adhesion (possibly
complicated by tribochemical interactions), and diffusion may primarily govern the CBN tool wear in hard turning. Further,
wear rate modeling including one approach developed in a recent study, on both crater and flank wear, is discussed as well.
In conclusion, a summary of the CBN tool wear survey and the future work are outlined. 相似文献
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Hongwan Jiang Lin He Zhongwei Ren Gang Zhan Zhongfei Zou 《The International Journal of Advanced Manufacturing Technology》2018,98(5-8):1069-1080
The loose layer can appear on the rake face of a turning tool under certain cutting conditions and have an important influence on the rake face wear. In this paper, wear morphology and wear mechanism of loose layer on the rake face of the original turning tool and the new cemented carbide micro groove turning tool developed independently during the cutting process are studied, by the combination of theoretical analysis and cutting test. And the relationships between the diffusion wear and the adhesive wear of the loose layer on the rake face of the new micro groove turning tool are further analyzed and revealed. The research results show that the loose layer on the rake face of two turning tools is caused by the diffusion wear, which is formed by the brittleness-weakening of tool material in the region resulting from elements diffusion. Meanwhile, the wear degree of the rake face of tools is aggravated by the mutual promotion of diffusion wear and adhesive wear. In the normal wear stage, the degree of looseness and brittleness of the rake face of the original turning tool is greater than the one of the micro groove turning tool. In the severe wear stage, cobalt elements in the rake face of the two turning tools are dissolved and diffused in varying degrees, which further aggravates the brittle-weakening of materials in the region. But the degree of loose brittleness of the rake face of the original turning tool is still greater than the one of the micro groove turning tool. It can be concluded that the micro groove on the rake face of the new turning tool can improve the rake face wear to a certain extent. 相似文献
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Zhiyu Zhang Jiwang Yan Tsunemoto Kuriyagawa 《The International Journal of Advanced Manufacturing Technology》2011,57(1-4):117-125
Tool wear is one of the most critical problems in machining hard, brittle materials. In the present work, diamond turning experiments were performed on reaction-bonded silicon carbide, and the tool wear characteristics were investigated. A special kind of wear pattern, namely periodical groove wear, was identified on the flank face of the tool, where the periodicity of the microgrooves was the same as the tool feed. Geometrical analysis showed that the periodical groove wear was caused by the tool feed marks on the machined surface. Laser micro-Raman spectroscopy indicated that the high-pressure abrasive wear at the tool?Cworkpiece interface dominates the wear behavior, rather than the diamond?Cgraphite transformation. By swinging the tool around its curvature center during the cutting process, the periodical groove wear pattern was suppressed, and the tool wear was reduced significantly. 相似文献
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Jinyang Xu Zhiqiang Liu Guoqiang Guo Ming Chen 《The International Journal of Advanced Manufacturing Technology》2013,67(1-4):517-533
AISI 1215 is a new kind of green and non-toxic free-cutting steel with minimum environmental pollution and excellent machinability, which receives wide promotion, investigation, and application in manufacturing industries. In machining of AISI 1215 steel, tool wear has a close relation with the presence of manganese sulfide lubricant zone formed on the tool surface. In this work, with the aid of cutting temperature and tool Von Mises stress simulations, tool wear analysis on the uncoated and multi-layer (Al2O3/TiCN) coated carbide tools was performed in high-speed turning operation. Wear pattern and wear mechanisms were studied through the experimental results. The main findings showed that the uncoated tool suffered high cutting temperature and severe tool wear and was not conducive to form a manganese sulfide lubricant zone in the turning operation. In contrast, the multi-layer coated tool could form a manganese sulfide lubricant zone on the chip–tool contact area. The beneficial roles of the manganese sulfide lubricant zone formed on the coated tool surface can be summarized as lubrication and diffusion blocking. The main wear mechanisms of the uncoated tool were crater wear, oxidation wear, adhesive wear, and abrasive wear, whereas for the multi-layer coated tool, they were crater wear, adhesive wear, and abrasive wear. 相似文献
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Very substantial tool wear may arise during machining processes because of chemical affinities between tool and workpiece. Studies have been made of this type of wear by observing the performance under various conditions of diamond tools turning steel, nickel and graphite, of tungsten tools turning graphite, and of CuNi tools turning sulphur. The reactions involved in the wear processes are insensitive to thermal activation and appear to be due to the reactivity of the atomically clean surfaces generated by the machining. The rates of wear are considerably modified both by changes in the chemical composition of tool and workpiece and by changes in the gaseous environment. It is clear that reactions between solid surfaces are at present not well understood and are worthy of further study. The results suggest possible ways of reducing tool wear both in turning and in other operations. 相似文献
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Ning Fang P. Srinivasa Pai S. Mosquea 《The International Journal of Advanced Manufacturing Technology》2011,52(1-4):65-77
High-speed machining has been receiving growing attention and wide applications in modern manufacture. Extensive research has been conducted in the past on tool flank wear and crater wear in high-speed machining (such as milling, turning, and drilling). However, little study was performed on the tool edge wear??the wear of a tool cutting edge before it is fully worn away??that can result in early tool failure and deteriorated machined surface quality. The present study aims to fill this important research gap by investigating the effect of tool edge wear on the cutting forces and vibrations in 3D high-speed finish turning of nickel-based superalloy Inconel 718. A carefully designed set of turning experiments were performed with tool inserts that have different tool edge radii ranging from 2 to 62???m. The experimental results reveal that the tool edge profile dynamically changes across each point on the tool cutting edge in 3D high-speed turning. Tool edge wear increases as the tool edge radius increases. As tool edge wear dynamically develops during the cutting process, all the three components of the cutting forces (i.e., the cutting force, the feed force, and the passive force) increase. The cutting vibrations that accompany with dynamic tool edge wear were analyzed using both the traditional fast Fourier transform (FFT) technique and the modern discrete wavelet transform technique. The results show that, compared to the FFT, the discrete wavelet transform is more effective and advantageous in revealing the variation of the cutting vibrations across a wide range of frequency bands. The discrete wavelet transform also reveals that the vibration amplitude increases as the tool edge wear increases. The average energy of wavelet coefficients calculated from the cutting vibration signals can be employed to evaluate tool edge wear in turning with tool inserts that have different tool edge radii. 相似文献
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J. M. Zhou M. Andersson J. E. Stahl 《The International Journal of Advanced Manufacturing Technology》2003,22(9-10):697-702
In precision hard turning, tool flank wear is one of the major factors contributing to the geometric error and thermal damage in a machined workpiece. Tool wear not only directly reduces the part geometry accuracy but also increases the cutting forces drastically. The change in cutting forces causes instability in the tool motion, and in turn, more inaccuracy. There are demands for reliably monitoring the progress of tool wear during a machining process to provide information for both correction of geometric errors and to guarantee the surface integrity of the workpiece. A new method for tool wear monitoring in precision hard turning is presented in this paper. The flank wear of a CBN tool is monitored by feature parameters extracted from the measured passive force, by the use of a force dynamometer. The feature parameters include the passive force level, the frequency energy and the accumulated cutting time. An ANN model was used to integrate these feature parameters in order to obtain more reliable and robust flank wear monitoring. Finally, the results from validation tests indicate that the developed monitoring system is robust and consistent for tool wear monitoring in precision hard turning. 相似文献