金屬表面氧化物激光去除的過程分析
Process analysis of laser removal of metal oxides

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摘要 激光去除金屬氧化物是一種很有效地激光清洗案例,在對整個去除過程分析時，無論直接采集激光誘導等離子體的特征輻射,還是用激光蒸發(fā)樣品后由其它光源再激發(fā)而進行光譜分析,都是非常有吸引力的研究課題。對影響等離子體激發(fā)過程的因素分析，有助于我們探究激光誘導等離子體光譜特性形成的機理。在許多科研工作者廣泛研究激光誘導等離子體特性的同時,推動了激光光譜分析技術的向前發(fā)展。本論文基于激光誘導等離子體技術來分析金屬表面氧化物被去除的整個過程。
本文首先綜述了國內外前人對這一主題的研究成果，并且簡單介紹了等離子體的誘導機制和等離子體光譜的分析方法，闡述了光強，光譜特征，電子密度等方面的理論。實驗采用3J的Nd:YAG激光器分五次脈沖作用于船用鋼鐵樣品表面上，同時以延遲時間為750ns的數字脈沖延遲器開始工作，以控制中階梯光柵光譜儀來接收由光纜傳輸進來的等離子體輻射信號。根據電腦獲取的光譜圖，我們重點分析了等離子體光譜特征，光強變化，電子密度等參數隨著激光脈沖作用次數的變化。實驗表明，因為等離子體的韌致效應和復合輻射效應，光譜整體呈現，連續(xù)譜為底，線狀譜分立疊加在上的光譜特征。隨著發(fā)射激光脈沖次數的增多，電子密度上升，然而隨著氧化層被去除徹底，電子密度曲線趨于平緩。各個元素的譜線強度都有增加。
關鍵詞 激光 金屬氧化物 等離子體 光譜法 去除過程

Process analysis of laser removal of metal oxides
Abstract Laser removal of metal oxide is a kind of very effective laser cleaning case, on the removal process analysis, whether direct acquisition of the laser induced plasma characteristic radiation, or by laser evaporation samples by other light excitation and spectral analysis, are very attractive research topic. Analysis on the factors affecting the plasma excitation process, the mechanism can help us to explore the spectral characteristics of laser induced plasma formation. Laser induced plasma characteristics widely studied in many research workers at the same time, pushing forward the development of laser spectroscopy.Laser induced material to analyze the whole process of metal oxide surface was removed to produce plasma characteristics in function and material based on.
This paper firstly summarizes the results of previous studies on this topic, and briefly introduces the analysis method of plasma induced mechanism and plasma spectroscopy. Introduced in the spectral analysis, intensity, spectral characteristics, the theoretical basis of the electronic density. Using Nd:YAG 3Jfive laser pulses to the marine steel sample surface, and at the same time, delay time of 750ns digital pulse delay circuit starts to work, in order to control the echelle spectrometer to receive the plasma radiation signal in the optical cable transmission. According to the spectra of computer access, we focus on the analysis of the plasma spectra, light intensity, electron density and other parameters change with the number of laser pulses.Because plasma bremsstrahlung and compound radiation effect, spectral overall presentation, continuous spectrum for the bottom, line spectrum discrete spectral characteristics of superimposed on. With the laser pulse is divided into laser pulse energy enhancement, the electron density increased, however, along with the oxide layer is removed completely, the electron density curve tends to be gentle.spectral line intensity of each element are added.
Keywords laser metallic oxide Plasma Spectral method Removal process


目 錄


第一章 緒論 1
1.1 引言 1
1.2 等離子體光譜分析的研究現狀 1
1.2.1發(fā)展概述 1
1.2.2 聲波法監(jiān)測激光除銹 1
1.2.3光譜法監(jiān)測激光清洗鈦合金 3
1.2.4等離子光譜的分析 6
1.3 本論文的主要工作 7
第二章 激光與材料的相互作用機理 8
2.1激光與材料作用的一般規(guī)律 8
2.2等離子體 10
2.3激光誘導等離子體的形成機理 10
2.4等離子體光譜分析 12
2.4.1三大假設條件 12
2.4.2 連續(xù)譜與線狀譜 12
2.4.3激光誘導等離子體電子密度理論分析 14
2.4.4光譜譜寬 15
2.5關于鋼鐵的腐蝕 16
第三章 光譜法分析激光去除金屬氧化物的過程 18
3.1 引言 18
3.2 實驗裝置 18
3.3 實驗結果及分析 19
3.3.1光譜譜線分析 21
3.3.2 隨著脈沖次數增加的譜線強度的分析 22
3.3.3 隨著脈沖次數增加的的電子數密度變化分析 24
3.4 總結 26
結 論 27
致 謝 28
參考文獻 29