共查询到20条相似文献,搜索用时 33 毫秒
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STUDYONULTRASONICVIBRATIONDRILLINGINCARBONFIBERREINFORCEDPOLYMERSZhangQixin;SunShiyu(HarbinInstituteofTechnologyFactory529,Be... 相似文献
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小孔的振动钻削与普通钻削的比较 总被引:3,自引:0,他引:3
本研究用特殊的万向联轴器作为振动源,进行了钻孔个数、加工精度、深孔加工适用性等方面的试验,获得了较好的效果,证明了这种振动钻孔方注对小孔加工的适用性. 相似文献
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为了实现高效率、高质量、低损伤的硬脆材料加工,对工件或砂轮同时施加砂轮轴向和径向的超声振动,该方法的显著特点是磨粒切削轨迹呈三维空间螺旋线型,将其定义为超声振动螺线磨削方法。在磨削工艺和二维超声振动的多参数共同作用下,材料去除机理产生复杂变化,表面微观形貌创出过程变得极其复杂。为此,提出一种超声振动螺线磨削加工表面数值仿真方法。基于超声振动螺线磨削几何映射关系,建立磨粒相对工件的空间螺旋线切削运动模型,进而给出超声振动螺线磨削加工表面生成模型,模拟出普通磨削和超声振动磨削的三维表面微观形貌,对比分析了超声振动对表面形成过程的影响规律。最后将仿真表面与磨削试验表面对比,发现两者微观形貌特征规律基本一致,验证了仿真方法的正确性和有效性。 相似文献
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利用有限元技术对微细钻头超声轴向振动钻入横向偏移过程进行深入分析。结果表明,超声轴向振动钻削从根本上改变了普通钻削的钻入机理,减小了横向偏移量,提高了钻入定心精度,特别适合硬脆材料上的微小孔的精密和超精密加工。 相似文献
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为解决SiC陶瓷加工时容易出现崩边、裂纹等问题,结合仿真与实验对其进行旋转超声振动套磨制孔技术研究。根据SiC陶瓷宏观力学本构模型,建立SiC陶瓷制孔仿真有限元模型并进行加工过程仿真分析,相比常规制孔,超声振动制孔的仿真轴向力最大可减小26.1%。常规加工和超声振动加工的对比实验研究表明,旋转超声振动加工可减小轴向力达32.9%,可大幅减少陶瓷材料脆性断裂,显著改善孔壁表面质量。有限元仿真与实验研究所得的轴向力在超声振动下最大相差7.5%,常规条件下两者最大相差14%,验证了有限元模型的正确性。仿真和实验研究结果表明:超声振动加工可显著减小轴向力和刀具磨损、提高刀具耐用度、改善制孔质量、降低加工成本。 相似文献
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Jun Wei Liu Dae Kyun Baek Tae Jo Ko 《The International Journal of Advanced Manufacturing Technology》2014,72(9-12):1527-1535
Ultrasonic machining (USM) has been considered as a new cutting technology that does not rely on the conductance of the workpiece. USM presents no heating or electrochemical effects, with low surface damage and small residual stresses on workpiece material, such as glass, ceramics, and others; therefore, it is used to drill microholes in brittle materials. However, this process is very slow and tool wear dependent, so the entire process has low efficiency. Therefore, to increase microhole drilling productivity or hole quality, rotary ultrasonic machining (RUM) is considered as a strong alternative to USM. RUM, which presents ultrasonic axial vibration with tool rotation, is an effective solution for improving cutting speed, precision, tool wear, and other machining responses beyond those of the USM. This study aims to reduce the microchipping or cracking at the exit of the hole, which inevitably occurs when brittle materials are drilled, with consideration of tool wear. To this end, response surface analysis and desirability functions are used for experimental optimization. The experimental results showed that the proposed RUM scheme is suitable for microhole drilling. 相似文献
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Yin-Sheng Fan Ji-Cheng Bai 《The International Journal of Advanced Manufacturing Technology》2018,94(9-12):3019-3028
The ultrasonic-assisted drilling (UAD) process is a technology which applies high frequency vibrations (>20 kHz) at amplitudes of 2–20 μm in the feed direction to the drill tip in order to improve machining conditions and productivity. Past work in this field is reviewed, noting the valuable foundation provided by laboratory-based research systems. This work is aimed at the development of a robust UAD module, fully compatible with computer numerical control (CNC) systems, and able to function in a production environment, describing results of drilling tests on 4340 steel. The UAD module, designed using FEA methods, with a 16-mm carbide drill, attached by shrink fit, is used to study the effects of ultrasonics on thrust force, torque, surface quality, hole size, and the microstructure of drilled 4340 steel.In order to provide a better understanding of the performance of this module, two different test scenarios were designed and the results for each were compared with the results obtained from baseline settings for conventional drilling. The results show that ultrasonic vibrations not only can reduce the average values of thrust force and torque but also can improve the surface quality of the hole. It is also found that a major increase in productivity could be achieved by using ultrasonic vibrations. Finally, the effects of ultrasonic vibrations on hardness and microstructure of the drilled hole is assessed and the results show that high frequency vibrations do not have significant effect on dimensional accuracy or on the microstructure of the drilled holes. 相似文献
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针对旋转超声钻用于建筑装修时,噪声小而效率偏低的问题,笔者进行了振动钻机构原理创新与试验研究。首先,搭建了高低频复合旋转超声的试验振动样机,可以实现稳定的高低频复合轴向振动钻孔作业;其次,以黏土砖为对象,进行了钻孔效率试验与振动分析,低频振动的引入,虽然使超声锤击工件表面的时间缩短了80%,但在进给力基本不变的条件下,钻孔速度提高了一倍左右,噪声仍可控制在60dB(A);最后,结合振动特性分析可以推断,在高低频复合振动钻孔过程中,超声振动主要负责对脆性材料的破碎作业,而低频振动主要负责将破碎后形成的颗粒快速离开切削区,从而提高钻进速度。因此,高低频复合振动钻进新原理,可以发挥高频振动与低频振动的优势,有望发展为一类新型钻孔装备。 相似文献
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横向超声振动对金刚石线锯切割硬脆材料锯切力及临界切削深度的影响 总被引:1,自引:1,他引:1
硬脆晶体材料,如SiC、Ge和Si等,由于其临界切削深度极小,常规加工方法很难实现塑性模式加工,研究横向超声振动金刚石线锯对硬脆材料锯切力和临界切削深度的影响有重要意义。在研究线锯受迫振动的基础上,分析金刚石线锯在横向超声波激励下柔性旋转点切割硬脆材料的条件;用特征函数对超声激励下金刚石线锯的振动切割状态进行表征;应用磨削理论建立了单颗金刚石磨粒切割硬脆材料的力学模型;推导出超声振动激励下金刚石线锯锯切硬脆材料临界切削深度的计算公式。以单晶SiC为对象,进行了超声振动线锯切割和普通线锯切割对比试验。结果表明相同条件下,超声振动线锯切割SiC的锯切力比普通线锯的锯切力减少22.4%~64.2%,临界切削深度增加1倍,晶片表面粗糙度有明显的改善。试验结果与理论分析具有良好的一致性。 相似文献
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实验分析了硬脆材料旋转超声磨削过程中刀具结合剂类型对加工性能的影响以便提高加工精度和加工表面的完整性.首先,采用能谱分析研究了铁基、陶瓷基和青铜基3种超声振动刀具中结合剂与金刚石颗粒的把持形式,并根据相同加工工艺条件下刀具磨损形式确定了把持力大小.然后,结合超声振动刀具特性,通过旋转超声磨削加工实验研究刀具结合剂类型与切削力、刀具磨损量、加工表面完整性的关系,并对实验结果进行了分析.实验结果表明:相对于陶瓷基和青铜基结合剂超声振动刀具,铁基结合剂超声振动刀具把持力最大,Z轴切削力平均值最小(为46.8 N);加工18 000 mm3材料后,刀具轴向磨损量最小(为0.1 mm);而陶瓷基结合剂超声振动刀具加工表面质量最好,表面粗糙度最大值为21.79 μm.结果证实铁基超声振动刀具适用于粗加工,陶瓷基超声振动刀具则适用于精加工. 相似文献
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Drilling by grinding is useful for fabricating holes in hard and brittle materials with high dimensional accuracy and low machining cost. However, its application to microholes has been limited to those with a diameter on the submillimeter order. The drilling of microholes less than 0.1 mm in diameter by grinding was therefore attempted on crown glass. Cemented tungsten carbide micropins were fabricated by electrical discharge machining and used as micro-grinding tools. They can be employed because the convex parts of discharge craters formed on the tool surfaces serve as cutting edges of abrasive grains of grinding wheels. In order to reduce grinding force and thus prevent tool breakage, ultrasonic grinding was employed with the workpieces ultrasonically oscillated. As a result, microholes down to 10 μm in diameter were successfully drilled. They are the smallest-diameter holes drilled by grinding, to the best of our knowledge. The effect of helical feeding, in which the tool not only rotates around its axis but also moves in planetary motion, on drilling properties was also investigated. 相似文献
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针对硬脆材料加工孔过程中出现的各种问题,选择一种有效的加工方法显得尤为重要.而旋转超声钻削加工已经成为一种有效的特种加工方法,其应用前景可观.综述了旋转超声加工技术的加工机理及发展历程,概述了国内外学者在硬脆材料工艺特性及装备研发等方面的研究成果,重点阐述了近年来国内外研究者在旋转超声钻削加工孔工艺特性方面的主要研究成... 相似文献
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Characteristics of chip generation by ultrasonic vibration cutting with extremely low cutting velocity 总被引:3,自引:3,他引:0
Professor Jeong-Du Kim In-Hyu Choi 《The International Journal of Advanced Manufacturing Technology》1998,14(1):2-6
Recently, mirror-surface machining of brittle materials such as ferrite, glass, and optical plastics has become more important, as these materials are used in optical communications and precision devices. Non-ferrous metals such as aluminium and copper were readily turned with diamond tools, but as the need for both infra-red and reflective optics escalated, the need to machine brittle materials arose. In this paper, ultrasonic vibration cutting at 20 kHz at extremely low cutting velocity for the precision machining of brittle plastics used for optical lenses is suggested and tested. The mechanism of chip generation, and characteristics of surfaces in the ductile mode, machined by ultrasonic vibration cutting are investigated. As a result, when micro cutting by ultrasonic vibration, it was confirmed that the chips generated by ductile mode cutting are obtained at 1/40 of the critical cutting velocity of the ultrasonic vibration cutting system, which is an extremely low cutting velocity. 相似文献
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深孔超声圆周振动钻削初探 总被引:1,自引:0,他引:1
针对深孔加工难度大的特点,采用超声圆周振动加工技术,在普通车床上附加一套振动装置。试验加工了几种不同材料,不同孔径的深孔,取得了较理想的效果,为进一步研究和推广深孔超声圆周振动加工技术提供了可靠的依据。 相似文献