本文選題：超聲波釬焊 + 超聲空化��； 參考：《哈爾濱工業(yè)大學(xué)》2014年碩士論文

【摘要】：本文主要研究了超聲波作用下窄間隙液態(tài)金屬內(nèi)部的超聲波空化效應(yīng)及其對(duì)母材表面的空蝕作用。目的在于揭示超聲波輔助釬焊過程當(dāng)中的超聲物理現(xiàn)象，深化認(rèn)識(shí)母材表面氧化膜破除的機(jī)制以及影響空蝕效果的因素，豐富超聲波輔助釬焊的理論研究。 首先采用高速攝像技術(shù)觀察窄間隙釬料池內(nèi)空化行為，主要觀察空化泡的形態(tài)、分布以及隨時(shí)間變化的特征并分析了影響空化強(qiáng)弱的因素，包括間隙、振幅及釬料種類。結(jié)果發(fā)現(xiàn)，在窄間隙金屬內(nèi)部空化泡的形態(tài)主要為瞬態(tài)空化泡，并且在板表面振幅均勻時(shí)，空化泡呈現(xiàn)中間多兩邊少的情況。空化泡在瞬態(tài)分布呈現(xiàn)不均勻性并且不是在所有位置都出現(xiàn)，但是在一段時(shí)間內(nèi)空化泡的分布比較均勻，基本所有位置都會(huì)出現(xiàn)。 研究了超聲波釬焊過程當(dāng)中的核心問題，即去除材料表面的氧化膜，超聲波釬焊之所以能夠焊接一些難焊的材料正是利用此點(diǎn)。分析了釬料池表面氧化膜的破除過程，即在氧化膜表面產(chǎn)生微裂紋—空蝕坑—空蝕坑擴(kuò)大—氧化膜完全破除，分析在超聲釬焊過程中影響空蝕的因素。 采用ANSYS模擬板表面的振幅分布，F(xiàn)LUENT模擬間隙內(nèi)部的聲壓分布情況，解釋之前觀察到的關(guān)于空化泡分布以及空蝕坑分布的現(xiàn)象。認(rèn)為板表面振幅越大導(dǎo)致間隙內(nèi)的聲壓越大，，造成空化效應(yīng)越強(qiáng)導(dǎo)致空蝕效果越明顯。
[Abstract]:In this paper, the ultrasonic cavitation effect of liquid metal with narrow gap and its cavitation erosion on the base metal surface under the action of ultrasonic wave are studied. The purpose of this paper is to reveal the ultrasonic physical phenomena in the process of ultrasonic assisted brazing, to deepen the understanding of the mechanism of oxide film breaking on the base metal surface and the factors affecting the cavitation corrosion effect, and to enrich the theoretical study of ultrasonic assisted brazing. The cavitation behavior in the narrow gap brazing pool was observed by high speed camera technique. The morphology, distribution and variation characteristics of cavitation bubbles with time were observed, and the factors affecting the cavitation intensity, including clearance, amplitude and type of solder, were analyzed. The results show that the cavitation bubble in the narrow gap metal is mainly transient cavitation bubble, and when the amplitude of the plate surface is uniform, the cavitation bubble appears to be more and less in the middle. Cavitation bubbles are distributed inhomogeneously in transient state and not in all locations, but they are more uniform in a certain period of time, and almost all of them will appear. The core problem of ultrasonic brazing is to remove the oxide film from the surface of materials. The reason why ultrasonic brazing can weld some difficult materials is to make use of this point. The process of breaking the oxide film on the surface of the solder pool is analyzed, that is, the micro-crack, the cavitation pit, the expansion of the cavitation pit and the oxide film are completely broken on the surface of the oxide film, and the factors affecting the cavitation erosion in the ultrasonic brazing process are analyzed. The amplitude distribution on the surface of the plate was simulated by ANSYS and fluent was used to simulate the sound pressure distribution inside the gap to explain the phenomena of cavitation bubble distribution and cavitation pit distribution observed before. It is considered that the larger the amplitude of the plate surface is, the greater the sound pressure in the gap is, and the stronger the cavitation effect is, the more obvious the cavitation effect is.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TG454;TB559

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 李國棟;栗卓新;張?zhí)炖?馬司鳴;;超聲波輔助釬焊技術(shù)的研究進(jìn)展[J];機(jī)械工程材料;2013年01期

2 王萍輝;超聲空化影響因素[J];河北理工學(xué)院學(xué)報(bào);2003年04期

本文編號(hào)：1783513