二元雙相塊體納米晶Ag-25Ni合金腐蝕性能研究
發(fā)布時(shí)間：2018-12-26 17:02
【摘要】：有關(guān)納米材料在各種溶液中穩(wěn)定性的研究,已引起人們的高度關(guān)注。迄今為止,國(guó)內(nèi)外在這方面的研究還主要集中在表面納米化、納米薄膜及納米涂層上,而對(duì)塊體尤其是塊體納米晶二元雙相合金腐蝕性能的研究還是相對(duì)較少。本文采用機(jī)械合金化法(MA)和液相還原法(LPR)通過(guò)優(yōu)化合成參數(shù)制備納米晶Ag-25Ni合金粉末,利用真空熱壓技術(shù)通過(guò)優(yōu)化熱壓參數(shù)制備了塊體納米晶Ag-25Ni合金,并與粉末冶金法(PM)制備的塊體常規(guī)尺寸Ag-25Ni合金對(duì)比,利用電化學(xué)工作站,通過(guò)極化曲線(xiàn)、交流阻抗譜、平均活化能以及Mott-Schottky曲線(xiàn)等測(cè)試,研究了它們?cè)谥行訬aCl、H_2SO_4和酸性NaCl溶液中的腐蝕性能以及顯微組織細(xì)化對(duì)其腐蝕性能的影響,結(jié)果表明:(1)三種合金的顯微組織如晶粒尺寸、相的結(jié)構(gòu)與分布存在差異。粉末冶金法制備塊體常規(guī)尺寸合金顯微組織極不均勻,組元間固溶度很低;機(jī)械合金化法制備塊體納米晶合金顯微組織比較均勻,組元間有一定固溶度,而液相還原法制備塊體納米晶合金顯微組織均勻,組元間固溶度較低;(2)向中性Na_2SO_4溶液中加入NaCl、H_2SO_4和酸性Na Cl溶液后,不同方法制備的三種PM Ag-25Ni、LPR Ag-25Ni和MAAg-25Ni合金的腐蝕電流密度增大,且隨著溶液濃度的增加,三種合金的腐蝕電流密度均增大。晶粒細(xì)化后,納米晶MAAg-25Ni合金的腐蝕速度降低,而納米晶LPRAg-25Ni合金腐蝕速度則加快;(3)在中性NaCl溶液中,不同方法制備的三種Ag-25Ni合金的交流阻抗譜均由單容抗弧組成,腐蝕過(guò)程受電化學(xué)反應(yīng)控制。在H_2SO_4溶液中,MAAg-25Ni和PMAg-25Ni合金的交流阻抗譜為單容抗弧,而LPRAg-25Ni合金則出現(xiàn)擴(kuò)散尾,腐蝕過(guò)程受擴(kuò)散控制。在酸性NaCl溶液中,PMAg-25Ni合金的交流阻抗由單容抗弧組成,而LPRAg-25Ni和MA Ag-25Ni合金出現(xiàn)擴(kuò)散尾。三種合金的電荷傳遞電阻變化趨勢(shì)與腐蝕電流密度相反;(4)在中性NaCl、H_2SO_4和酸性NaCl溶液中,不同方法制備的三種Ag-25Ni合金均出現(xiàn)鈍化現(xiàn)象,晶粒細(xì)化并沒(méi)有改變鈍化膜半導(dǎo)體的類(lèi)型,均為n型半導(dǎo)體。在中性NaCl和酸性NaCl溶液中,三種合金表面形成的鈍化膜的載流子密度大小按LPRAg-25NiPM Ag-25NiMA Ag-25Ni合金的順序降低。在H_2SO_4溶液中,鈍化膜的載流子密度大小按LPRAg-25NiMAAg-25NiPMAg-25Ni合金的順序降低,與三種合金的維鈍電流大小規(guī)律相符。
[Abstract]:The study on the stability of nanomaterials in various solutions has attracted much attention. Up to now, the researches in this field have mainly focused on the surface nanocrystalline, nanocrystalline films and nanocrystalline coatings at home and abroad, but the corrosion properties of bulk, especially bulk nanocrystalline binary dual phase alloys, have been relatively few. Nanocrystalline Ag-25Ni alloy powder was prepared by mechanical alloying method (MA) and liquid phase reduction method (LPR) by optimizing synthesis parameters. Bulk nanocrystalline Ag-25Ni alloy was prepared by vacuum hot pressing technology by optimizing hot pressing parameters. Compared with the conventional bulk Ag-25Ni alloy prepared by powder metallurgy method (PM), the electrochemical workstation was used to study their effect on neutral NaCl, by means of polarization curve, AC impedance spectrum, average activation energy and Mott-Schottky curve. The corrosion resistance of H_2SO_4 and acid NaCl solution and the effect of microstructure refinement on their corrosion resistance are discussed. The results show that: (1) the microstructure, phase structure and distribution of the three alloys are different, such as grain size. The microstructure of conventional bulk alloy prepared by powder metallurgy method is very uneven, and the solution between components is very low. The microstructure of bulk nanocrystalline alloy prepared by mechanical alloying method is uniform, and there is a certain solution degree among the components, while the microstructure of bulk nanocrystalline alloy prepared by liquid phase reduction method is uniform, and the solution degree between components is low. (2) the corrosion current density of three kinds of PM Ag-25Ni,LPR Ag-25Ni and MAAg-25Ni alloys prepared by different methods increased after adding NaCl,H_2SO_4 and acidic Na Cl solution to neutral Na_2SO_4 solution, and the corrosion current density increased with the increase of solution concentration. The corrosion current density of the three alloys increased. After grain refinement, the corrosion rate of nanocrystalline MAAg-25Ni alloy decreased, while that of nanocrystalline LPRAg-25Ni alloy accelerated. (3) in neutral NaCl solution, the AC impedance spectra of three kinds of Ag-25Ni alloys prepared by different methods are all composed of single capacitive reactance arc, and the corrosion process is controlled by electrochemical reaction. In H_2SO_4 solution, the AC impedance spectrum of MAAg-25Ni and PMAg-25Ni alloys is single capacitive reactance arc, while that of LPRAg-25Ni alloy is diffusion tail, and the corrosion process is controlled by diffusion. In acidic NaCl solution, the AC impedance of PMAg-25Ni alloy is composed of single capacitive reactance arc, while the diffusion tail of LPRAg-25Ni and MA Ag-25Ni alloys appears. The change trend of charge transfer resistance of the three alloys is opposite to the corrosion current density. (4) in neutral NaCl,H_2SO_4 and acid NaCl solution, the three kinds of Ag-25Ni alloys prepared by different methods all appear passivation phenomenon, the grain refinement does not change the type of passivation film semiconductor, all of them are n-type semiconductors. In neutral NaCl and acidic NaCl solutions, the carrier density of passivated films formed on the surface of the three alloys decreased in the order of LPRAg-25NiPM Ag-25NiMA Ag-25Ni alloys. In H_2SO_4 solution, the carrier density of the passivated film decreases in the order of LPRAg-25NiMAAg-25NiPMAg-25Ni alloy, which is consistent with the law of the magnitude of the three alloys.
【學(xué)位授予單位】：沈陽(yáng)師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：TB383.1;TG178
本文編號(hào)：2392420
[Abstract]:The study on the stability of nanomaterials in various solutions has attracted much attention. Up to now, the researches in this field have mainly focused on the surface nanocrystalline, nanocrystalline films and nanocrystalline coatings at home and abroad, but the corrosion properties of bulk, especially bulk nanocrystalline binary dual phase alloys, have been relatively few. Nanocrystalline Ag-25Ni alloy powder was prepared by mechanical alloying method (MA) and liquid phase reduction method (LPR) by optimizing synthesis parameters. Bulk nanocrystalline Ag-25Ni alloy was prepared by vacuum hot pressing technology by optimizing hot pressing parameters. Compared with the conventional bulk Ag-25Ni alloy prepared by powder metallurgy method (PM), the electrochemical workstation was used to study their effect on neutral NaCl, by means of polarization curve, AC impedance spectrum, average activation energy and Mott-Schottky curve. The corrosion resistance of H_2SO_4 and acid NaCl solution and the effect of microstructure refinement on their corrosion resistance are discussed. The results show that: (1) the microstructure, phase structure and distribution of the three alloys are different, such as grain size. The microstructure of conventional bulk alloy prepared by powder metallurgy method is very uneven, and the solution between components is very low. The microstructure of bulk nanocrystalline alloy prepared by mechanical alloying method is uniform, and there is a certain solution degree among the components, while the microstructure of bulk nanocrystalline alloy prepared by liquid phase reduction method is uniform, and the solution degree between components is low. (2) the corrosion current density of three kinds of PM Ag-25Ni,LPR Ag-25Ni and MAAg-25Ni alloys prepared by different methods increased after adding NaCl,H_2SO_4 and acidic Na Cl solution to neutral Na_2SO_4 solution, and the corrosion current density increased with the increase of solution concentration. The corrosion current density of the three alloys increased. After grain refinement, the corrosion rate of nanocrystalline MAAg-25Ni alloy decreased, while that of nanocrystalline LPRAg-25Ni alloy accelerated. (3) in neutral NaCl solution, the AC impedance spectra of three kinds of Ag-25Ni alloys prepared by different methods are all composed of single capacitive reactance arc, and the corrosion process is controlled by electrochemical reaction. In H_2SO_4 solution, the AC impedance spectrum of MAAg-25Ni and PMAg-25Ni alloys is single capacitive reactance arc, while that of LPRAg-25Ni alloy is diffusion tail, and the corrosion process is controlled by diffusion. In acidic NaCl solution, the AC impedance of PMAg-25Ni alloy is composed of single capacitive reactance arc, while the diffusion tail of LPRAg-25Ni and MA Ag-25Ni alloys appears. The change trend of charge transfer resistance of the three alloys is opposite to the corrosion current density. (4) in neutral NaCl,H_2SO_4 and acid NaCl solution, the three kinds of Ag-25Ni alloys prepared by different methods all appear passivation phenomenon, the grain refinement does not change the type of passivation film semiconductor, all of them are n-type semiconductors. In neutral NaCl and acidic NaCl solutions, the carrier density of passivated films formed on the surface of the three alloys decreased in the order of LPRAg-25NiPM Ag-25NiMA Ag-25Ni alloys. In H_2SO_4 solution, the carrier density of the passivated film decreases in the order of LPRAg-25NiMAAg-25NiPMAg-25Ni alloy, which is consistent with the law of the magnitude of the three alloys.
【學(xué)位授予單位】：沈陽(yáng)師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：TB383.1;TG178
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 Wen-Xiu He;Yong-Qiang Zhang;Qian-Qing Liang;Wen-Quan Jiang;Hai-Feng Sun;;Hydrothermal synthesis and characterization of nano-petal nickel hydroxide[J];Rare Metals;2015年09期
2 ;Chemical composition and Mott-Schottky analysis of passive film formed on G3 alloy in bicarbonate/carbonate buffer solution[J];Acta Metallurgica Sinica(English Letters);2010年06期
3 孟國(guó)哲;李瑛;王福會(huì);;納米Fe-10Cr涂層電化學(xué)腐蝕行為影響研究 I.鈍化性能[J];中國(guó)腐蝕與防護(hù)學(xué)報(bào);2007年01期
4 肖正偉;曾振歐;趙國(guó)鵬;田志斌;;納米TiO_2涂層的制備及其在金屬腐蝕防護(hù)中的應(yīng)用[J];腐蝕與防護(hù);2007年01期
5 陳洪杰,李志偉,趙彥保,張治軍,黨鴻辛;納米合金的制備進(jìn)展[J];化學(xué)進(jìn)展;2004年05期
6 李瑛,王福會(huì);表面納米化對(duì)金屬材料電化學(xué)腐蝕行為的影響[J];腐蝕與防護(hù);2003年01期
7 王崇琳,林樹(shù)智,趙澤良,牛焱,吳維;熱壓致密化塊體納米晶Ag50Ni50合金的顯微組織[J];中國(guó)有色金屬學(xué)報(bào);2001年05期
8 李瑛,王福會(huì),劉剛;表面納米化低碳鋼電化學(xué)行為尺寸效應(yīng)[J];中國(guó)腐蝕與防護(hù)學(xué)報(bào);2001年04期
9 石勁松,李曉男,張繼紅;納米材料及其在傳感器中的應(yīng)用[J];新技術(shù)新工藝;2001年06期
10 ;Surface Nanocrystallization (SNC) of Metallic Materials-Presentation of the Concept behind a New Approach[J];Journal of Materials Science & Technology;1999年03期
相關(guān)碩士學(xué)位論文 前1條
1 許宜民;納米晶銅塊體材料的本征電化學(xué)腐蝕行為研究[D];浙江大學(xué);2011年
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