共查询到20条相似文献,搜索用时 125 毫秒
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为探究超声辅助磨削过程中不同工具的磨损特征,采用电镀和钎焊两种金刚石磨头对碳化硅陶瓷进行了超声辅助磨削和普通磨削对比试验,研究了超声振动作用、工具类型对磨粒磨损形式及其变化过程的影响,在此基础上分析了磨粒磨损形式对工件表面质量的影响.试验结果表明:对于电镀磨头,普通磨削和超声辅助磨削过程中的磨粒磨损形式均以磨耗磨损和宏观破碎为主,超声振动作用可有效改善加工表面质量;而对于钎焊磨头,普通磨削的磨粒磨损形式主要是磨耗磨损和宏观破碎,超声辅助磨削的磨粒磨损形式主要是磨耗磨损和微破碎,初始阶段超声振动作用可改善表面质量,但随着磨削行程的增加,微破碎形式的占比增高,超声辅助磨削时的工件表面粗糙度值高于普通磨削时的工件表面粗糙度值. 相似文献
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超声振动挤压加工(超声压光)技术是利用超声电信号驱动振子前端的挤压工具头产生高频振动,对工件进行每秒数万次的冲击,使工件表面材料产生塑性变形。利用预压力可调式超声振动挤压加工系统对40Cr棒料进行振动挤压加工试验,得到了各加工参数对工件表面粗糙度的影响规律,并通过材料弹塑性理论和振动理论验证了此实验数据规律的正确性与可靠性;通过对挤压加工前后工件表面粗糙度的对比,表明此振动挤压加工系统可显著提高工件的表面质量。 相似文献
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磁力研磨是利用磁性磨料和磁场作用进行研磨加工的一种研抛技术.讨论了不同研磨头形状对磁力研磨的影响以及研磨头设计的要点.在五自由度并联机床上利用不同形状磨头对自由曲面的模具进行了磁力研磨试验.开槽研磨头比不开槽研磨头的研磨效果要好得多.实验分析了利用球型磨头对工件磁力研磨时,磁场强度、研磨间隙、研磨时间等因素对自由曲面模具表面研磨质量的影响.利用五自由度并联机床不仅可以去除自由曲面模具表面的切削残留痕迹,降低模具的表面粗糙度,还可解决传统手工研磨方式所引起的工件研磨质量不一致的缺陷。 相似文献
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机器人复合加工模具曲面的干涉回避与质量控制 总被引:1,自引:0,他引:1
提出一种由机器人和超声电火花复合研磨机等组成的自动研磨加工系统,对在模具曲面加工过程中出现的工具与工件之间可能产生的局部干涉现象进行了研究,通过干涉回避技术建立复合精加工表面质量的控制模型,并在试验中证实了理论的正确性。 相似文献
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空化效应是功率超声珩磨中最常见的现象,为探究空化对被加工材料性能的影响,对表面抛光后的AZ31B镁合金进行超声振动空化实验,采用正交试验研究了超声振幅、与工件距离、超声时间对试件硬度和表面粗糙度的影响,并对试件进行金相组织分析。结果表明:空化可以造成材料表面形貌的改变,并对材料的硬度和表面质量产生变化。影响材料硬度的主要因素依次是超声时间、与工件距离、超声振幅,空化可以将工件硬度提升1. 5-3倍左右,最优参数组合为超声振幅75%、与工件距离1. 0mm、超声时间20min;粗糙度的主要影响因素是与工件距离、超声时间和超声振幅,在超声时间20min、与工件距离2mm、超声振幅50%条件下,试件表面粗糙度Rq值最小,表面质量最好。在硬度最高的试验组条件下,表面晶粒尺寸由15μm减小到2μm左右。因此,超声空化在一定的控制条件下,能明显改善工件的硬度和表面质量,工件硬度的改变与超声空化导致晶粒细化现象有关,试验分析结果对材料改性有现实借鉴意义。 相似文献
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罗美丽 《中国制造业信息化》1999,(2):2
采用自行设计制造的加工装置,进行了磁性磨料磁力研磨工艺试验。试验结果表明:工件转速仅对加工效率有正比例影响;加工间隙的增大则引起加工效率的下降,加工表面粗糙度值的上升;存在磁通密度最佳值点,该条件下可获得较高的加工效率与加工质量;试验还表明在加工初期具有较高的金属去除率,表面粗糙度也下降较快。 相似文献
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Theoretical and Experimental Studies of Ultraprecision Machining of Brittle Materials with Ultrasonic Vibration 总被引:5,自引:1,他引:4
X. Wang M. Zhou J.G.-K. Gan B. Ngoi 《The International Journal of Advanced Manufacturing Technology》2002,20(2):99-102
Ductile machining of brittle materials, even at a high critical depth-of-cut, has been realised by applying ultrasonic vibration
to a diamond tool tip. A surface roughness Ra of 100 nm at a 2 μm depth-of-cut was achieved. A discussion on fundamental principles
of ultrasonic machining, the material removal mechanism and the calculation of critical factors are presented in this paper. 相似文献
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Ultrasonic elliptical vibration cutting is a very promising technique for the machining of brittle materials. However, its machining performance is currently limited by the ductile machining model and the machining strategy with a constant feed rate, leading to low machining efficiency. To overcome this defect, this paper presents a novel self-tuned ultrasonic elliptical vibration cutting (SUEVC) technique to achieve high-efficient ductile-regime machining of the micro-optics array on brittle materials. The proposed SUEVC includes a ductile-regime machining model and a tool path generation method. In SUEVC, the feed rate adaptively changes with respect to the local shape variation of the desired surface along the feeding direction to ensure both crack-free surface and high machining efficiency. Finally, two 1 × 3 spherical micro-optics arrays were successfully fabricated on single-crystal MgF2 by SUEVC and the traditional machining strategy respectively. Results demonstrated that the SUEVC could enhance the machining efficiency by 30% relative to the traditional machining strategy, while maintaining similar surface roughness and a crack-free surface. 相似文献
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Guangchao Han Jia Zhao Xingyun Wang 《The International Journal of Advanced Manufacturing Technology》2017,88(1-4):209-218
Ultrasonic-assisted machining was an effective method to improve the material removal quality especially to difficult-to-cut metal materials. The ultrasonic vibration was usually superimposed on the machining tool but seldom on the workpiece, although the ultrasonic vibration of workpiece could improve the processability of material more effectively. In this paper, a rectangle hexahedron ultrasonic sonotrode with optimized slots was developed as a platform to realize the assisted ultrasonic vibration of workpiece and the ultrasonic-assisted polishing process of austenitic stainless steel was also studied. The unbounded abrasive was selected as polishing medium, and the path compensation strategy of soft polishing tool was carried out for getting uniform polishing force. The orthogonal experiments were designed to study the optimization of ultrasonic polishing parameters and the relation between different types of ultrasonic polishing path and polishing quality. The results appear that the horizontal ultrasonic vibration of workpiece can reduce polishing force and improve polished surface roughness, which can also reinforce the proportion of plastic shear effect in the material removal process. The ultrasonic polishing path keeping consistent with workpiece vibration direction can get more uniform polishing force and better surface roughness. And the 45° oblique crossing ultrasonic path can get the maximum average polishing force reduction by 75.2 %. 相似文献
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The single-point diamond machining of several polymeric materials has been investigated. The final surface structure and roughness of the workpiece is determined by well-established fundamentals of polymer mechanics. Material is removed via ductile, brittle, or transitional mechanisms that depend on polymer properties such as glass transition temperature, relaxation time, degree of crosslinking, and viscosity. For some materials, the mechanism could be changed from ductile to brittle with a change of operating and tool parameters. In brittle materials, the surface roughness is largely controlled by the rake face angle of the diamond. For ductile workpieces, the melt viscosity of the polymer is important. Crosslinked materials are restricted from ductile behavior by the presence of chemical bonds. As a result, material removal occurs by rupture or an extreme fracture process. With an understanding of polymer behavior, suitability of new materials for single-point diamond machining can be assessed. The change of successful processing within the operating range of the tool can be determined with a minimum number of trial and error experiments. 相似文献
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分析了超声复合放电加工的机理,用微细电火花放电工艺制作了多种截面的微细工具电极。进行了超声和超声复合放电加工的试验,结果表明:超声加工是制作硬脆材料微结构的有效方法,制作的金属材料微结构有较好的精度,且加工效率高。 相似文献
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硬脆材料旋转超声加工技术的研究现状及展望 总被引:3,自引:0,他引:3
旋转超声加工是一种复合特种加工技术,它复合了传统超声加工和普通磨削加工的材料去除方式,在提高硬脆材料去除效率、减小切削力、提高加工精度和表面完整性等方面具有显著优势。自旋转超声加工技术发明至今,国内外学者开展了大量的有关旋转超声加工装备及工艺的研究工作,并且已在几乎所有主要的硬脆难加工材料中得到实际应用。本研究在简要概述旋转超声加工技术的基本原理和发展过程基础上,总结国内外学者在材料去除机理、工艺特性、加工新形式以及装备研发等几方面的主要研究成果,并对旋转超声加工技术的发展趋势及值得关注的问题进行展望。 相似文献
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首先介绍超声波表面光饰加工的原理,以航空工业中常见铝合金材料2D12及LC9为研究对象,采用超声波加工和常规加工对比的方法,研究超声波表面光饰加工技术对铝合金疲劳性能、表面组织及镀覆性能的影响。通过试验对比可以得出结论:超声波表面光饰加工使表面产生压应力,优化表层组织,大幅度提高表面粗糙度;表面硬质阳极氧化和镀铬后,镀(化)层质量不低于常规加工的试样;经过超声波表面光饰加工的试件疲劳寿命有较大幅度的提高。 相似文献