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1.
脆性光学材料的超声磨削实验研究   总被引:6,自引:0,他引:6  
分别采用超声磨削和普通磨削加工方法加工了几种脆性光学材料,研究了几种主要工艺参数对工件加工表面粗糙度的影响。结果表明,超声频率和振幅、金刚石磨料粒度、切深、工具的横向进给速度和旋转速度等工艺参数对表面粗糙度的影响较大。通过比较发现,超声磨削方法比普通磨削方法具有更好的加工表面粗糙度,更高的材料去除率,以及更低的工具磨损量。  相似文献
2.
用激光外差干涉仪探测金属表面超声振动的实验设计   总被引:2,自引:0,他引:2  
将激光外差法测量的科研成果转化为物理专业实验,设计了易于调节的激光外差干涉系统,实现了外差信号的接收,用压电超声装置代替激光超声装置,使实验系统小型化。  相似文献
3.
Frictional effect of ultrasonic-vibration on upsetting   总被引:2,自引:0,他引:2  
Hung JC  Tsai YC  Hung C 《Ultrasonics》2007,46(3):277-284
The ultrasonic-vibration ring compression test and finite element analysis were performed on aluminum alloy specimens to explore the frictional effect of superimposing ultrasonic-vibration during upsetting. The extrapolated compression test was first adopted to obtain the frictionless material properties for finite element analysis. Experimental results of extrapolated compression test also indicate that ultrasonic-vibration can reduce the compressive force when friction is eliminated and can increase the temperatures of a material at the same time.The following results of the hot extrapolated compression test and the hot ring compression test reveal that increasing temperature by ultrasonic-vibration may reduce the flow stress and increase the interfacial friction. Finally, finite element analysis was conducted to derive the friction calibration curves and to evaluate the friction factor.  相似文献
4.
Laser ultrasonics was applied to the manufacturing control of the integrity (no failure) of coated spherical particles designed for High Temperature Reactors (HTR). This control is of major importance, since the coating of the nuclear fuel kernel is designed to prevent from the diffusion of fission products outside the particle during reactor operation. The SiC layer composing the coating is particularly important, since this layer must be an impenetrable barrier for fission products. The integrity of the SiC shell (no crack within the shell) can be assessed by the ultrasonic vibration spectrum of the HTR particle, which is significantly changed, compared to the reference spectrum of a defect-free particle. Spheroidal vibration modes of defect-free dummy particles with a zirconium dioxide (ZrO2) core were observed in the 2-5 MHz range. A theoretical analysis is presented to account for the observed vibration spectra of defect-free or cracked HTR particles.  相似文献
5.
超声振动珩磨作用下空化泡动力学及影响参数   总被引:1,自引:0,他引:1       下载免费PDF全文
为了合理利用超声振动珩磨作用下的空化效应,以磨削区单个空化泡为研究对象,考虑珩磨头合成扰动速度和珩磨压力的作用建立了磨削区空化泡的动力学模型。数值模拟了空化泡初始半径,珩磨压力,液体静压力和超声声压幅值对磨削区空化效应的影响。研究表明考虑超声振动珩磨作用时,空化泡膨胀的幅值会受到抑制,其溃灭时间也会缩短,而且较容易出现稳态空化。珩磨压力和液体静压力对磨削区空化主要起抑制作用,超声波声压幅值在一定范围内能够促进磨削区空化效果的提升。本文的研究为进一步理解超声振动珩磨的空化机理提供了理论支持。  相似文献
6.
本文用有限元软件对超声复合振动系统中的局部共振现象进行了仿真计算.通过对仿真结果的分析,验证了“局部共振是耦合振动”的观点.在此基础上,用有限元方法进一步研究了截面直径比、工具杆长度等影响局部共振的因素,总结出了产生局部共振的条件.  相似文献
7.
应崇福 《应用声学》2006,25(6):380-383
对超声复合振动系统中的“局部共振”现象,基于熟知的棒或管中声波产生和传播的理论,提出一种机理解释。  相似文献
8.
林书玉 《应用声学》2000,19(4):31-34
本文提出了一种测量功率超声振动系统中振动速度比的简单方法。与传统的测量方法相比,本方法将力学量转变为电学量的测量,将绝对测量变成了相对测量,降低了对实验设备的要求,有利于提高测试精度。  相似文献
9.
本文介绍一种超声纸杯焊接设备及焊接工艺。  相似文献
10.
The recently proposed fixed-abrasive polishing process was revisited, but this paper focuses mainly on the potential influence of various liquids and the different kinds of pellets on the polishing process as well as the wear of pellet in ultrasonic assisted and conventional processes. The results show that using liquids is helpful in improving surface quality and lowering surface roughness. In particular, the surface roughness is improved sharply for pore-free pellet, from >80 nm to <1 nm (avg.) and the polishing process smoothly proceed that otherwise will hardly progress without liquids. However, the liquids do not necessarily always improve polishing process. There is an optimal volume for a specific polishing process. Moreover, the wear of pellet was also evaluated as well. The results suggest that applying ultrasonics can effectively alleviate the wear loss of pellet and increase the “G-ratio” of polishing process.  相似文献
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