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1.
超声波清洗设备的目前发展方向   总被引:10,自引:0,他引:10       下载免费PDF全文
辛乐 《应用声学》2000,19(2):44-48
超声波清洗设备的发展方向目前有二个:一个是从单缸机到多缸机或自动化的超声清洗生产线;另一个是,从低频超声清洗机到高频超声清洗机。  相似文献
2.
This paper describes investigations of the spatial distribution of cavitation activity generated within an ultrasonic cleaning vessel, undertaken using a novel cavitation sensor concept. The new sensor monitors high frequency acoustic emissions (>1 MHz) generated by micron-sized bubbles driven into acoustic cavitation by the applied acoustic field. Novel design features of the sensor, including its hollow, cylindrical shape, provide the sensor with spatial resolution, enabling it to associate the megahertz acoustic emissions produced by the cavitating bubbles with specific regions of space within the vessel. The performance of the new sensor has been tested using a 40 kHz ultrasonic cleaner employing four transducers and operating at a nominal electrical power of 140 W under controlled conditions. The results demonstrate the ability of the sensors to identify 'hot-spots' and 'cold-spots' in cavitation activity within the vessel, and show good qualitative agreement with an assessment of the spatial distribution of cavitation determined through erosion monitoring of thin sheets of aluminium foil. The implications of the studies for the development of reliable methods of quantifying the performance of cleaning vessels are discussed in detail.  相似文献
3.
光学元件超声清洗工艺研究   总被引:2,自引:1,他引:1  
系统开展了光学元件超声清洗工艺的实验研究。通过研究超声清洗剂、清洗温度等工艺参数的优化,找到了能够有效祛除元件表面无机污染物和有机污染物的较佳超声清洗工艺,且超声清洗没有对光学元件表面产生损伤,清洗后的光学元件接触角小于6°,并不残留大于1μm的颗粒,超声清洗对光学元件表面污染物的祛除能力远胜于手工清洗。  相似文献
4.
D. H. McQueen 《Ultrasonics》1990,28(6):422-427
The Galvani potential has been used to study the removal of solder flux from electronic circuit boards with and without ultrasound. First a theory of the Galvani potential as applied to decontamination studies is presented. Then theoretical decontamination curves are presented, based on simple chemical kinetics coupled to mass diffusion to and from the surface through a passive boundary layer. Finally, the theory is tested and illustrated by removal of solder flux from finger structures in various solvents including freon, Prelete, and isopropanol in water. Clear differences in how quickly the Galvani potential decreased with time were noted. The fastest results were obtained for 80% isopropanol in water, but it is likely that more metallic salts were left behind on the surface than in the slower methods. The saturation of the solvents is also discussed. Finally, methods of on-line testing solvents and circuit boards based on the Galvani potential are discussed.  相似文献
5.
声源分布和超声频率对清洗声场均匀性的优化*   总被引:1,自引:0,他引:1       下载免费PDF全文
驻波和换能器指向性等影响声场均匀性,造成清洗死角,影响清洗效果。采用COMSOL仿真软件建立了单个换能器位于底部的三维模型,通过染色法实验结果验证模型的有效性。研究了换能器同时位于底部和侧面、多排换能器位于底部时的声场,用声压幅值相对标准差来量化均匀性,发现该两种换能器分布方式能够有效优化声场均匀性。通过调节频率研究频率对声场的影响,进一步优化声场均匀性。对声源分布的确定、频率的选择以满足声场均匀化需求有指导意义。  相似文献
6.
A method for intensifying ultrasonic cavitation in water and aqueous solutions has been proposed, which consists of a chemical fixation of dissolved oxygen. The influence of selected reducing agents on the intensity of cavitation in water and alkaline solutions has been investigated.  相似文献
7.
Lin Shuyu 《Ultrasonics》1995,33(6):445-448
Langevin ultrasonic transducers are widely used in high-power ultrasonics and underwater sound. In ultrasonic cleaning, a matching metal horn rather than a metal cylinder is used as the radiator in order to enhance the radiating surface and improve the acoustic matching between the transducer and the processed medium. To raise the effect of ultrasonic cleaning, the standing wave in the cleaning tank should be eliminated. One method to eliminate the standing wave in the tank is to use the multifrequency ultrasonic transducer. In this paper, the Langevin ultrasonic horn transducer, with two resonance frequencies, is studied. The transducer consists of two groups of piezoelectric ceramic elements: the back metal cylinder, the middle metal cylinder and the front matching metal horn. The vibrational modes of the transducer are analysed, and resonance frequency equations of the transducer in the half-wave and the all-wave vibrational modes are derived. According to the resonance frequency equations, transducers with two resonance frequencies are designed and made. The resonance frequencies, the effective electromechanical coupling coefficients and the equivalent electric impedances of the transducers are measured. It is shown that the measured resonance frequencies are in good agreement with the computed results, and the transducer can be excited to vibrate at two resonance frequencies, which correspond to the half-wave and the all-wave vibrational modes of the transducer.  相似文献
8.
本文较详细地叙述了生产超声清洗机过程中,对换能器频率,频带宽度,阻抗等参数实施一种简单而实用的大功率测试法,据此进行筛选来提高超声清洗机的性能。  相似文献
9.
 研究了超声清洗和激光预处理两种后处理手段对减反膜的损伤特性的影响。采用电子束蒸发技术制备了1 064 nm减反膜,利用超声清洗及激光预处理的方法分别对样品进行处理,并对处理前后的样品分别进行激光损伤阈值测试及破斑深度测量。结果表明:处理后减反膜的损伤阈值均有所提升,但激光预处理的阈值增强效果更加明显;超声清洗前后的破斑深度没有大的变化,而激光预处理后的破斑深度比处理前浅得多;原因在于超声清洗只能去除表面杂质,激光预处理可减少和抑制膜层内较深处的缺陷。  相似文献
10.
Qin Hu 《Applied Surface Science》2010,256(20):5952-5956
To explore the machining characteristics of glassy carbon by focused ion beam (FIB), particles induced by FIB milling on glassy carbon have been studied in the current work. Nano-sized particles in the range of tens of nanometers up to 400 nm can often be found around the area subject to FIB milling. Two ion beam scanning modes - slow single scan and fast repetitive scan - have been tested. Fewer particles are found in single patterns milled in fast repetitive scan mode. For a group of test patterns milled in a sequence, it was found that a greater number of particles were deposited around sites machined early in the sequence. In situ EDX analysis of the particles showed that they were composed of C and Ga. The formation of particles is related to the debris generated at the surrounding areas, the low melting point of gallium used as FIB ion source and the high contact angle of gallium on glassy carbon induces de-wetting of Ga and the subsequent formation of Ga particles. Ultrasonic cleaning can remove over 98% of visible particles. The surface roughness (Ra) of FIB milled areas after cleaning is less than 2 nm.  相似文献
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