本文關(guān)鍵詞： TC4鈦合金 微弧氧化 C_3H_8O_3 結(jié)構(gòu) 耐蝕性　出處：《西南石油大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：鈦合金以其比強(qiáng)度高、生物相容性好等優(yōu)點(diǎn)被廣泛應(yīng)用于航空、航天、醫(yī)療等領(lǐng)域,但耐磨性差、硬度低限制了鈦合金的應(yīng)用。微弧氧化技術(shù)為解決這些問題提供了一個(gè)很好的思路。本文選用應(yīng)用最廣泛的TC4鈦合金為基體材料,研究工藝參數(shù)對(duì)TC4鈦合金微弧氧化膜結(jié)構(gòu)和性能的影響,為鈦合金氧化膜投入產(chǎn)業(yè)應(yīng)用提供一定的理論依據(jù),拓寬鈦合金的應(yīng)用范圍。本文采用恒定電流模式在Na2SiO3和Na3PO4為主鹽的電解液中對(duì)TC4鈦合金進(jìn)行微弧氧化,研究了電流密度、氧化時(shí)間和Na2SiO3濃度對(duì)膜層結(jié)構(gòu)和性能的影響。利用渦流膜層測(cè)厚儀、顯微維氏硬度計(jì)分別研究了膜層的厚度和硬度,利用SEM、XRD、EDS研究了膜層的微觀形貌、相組成、化學(xué)組成,利用電化學(xué)工作站研究了膜層的耐蝕性,利用球-盤摩擦磨損試驗(yàn)機(jī)和EDS研究了膜層的耐磨性能。在優(yōu)選工藝參數(shù)的基礎(chǔ)上添加C3H8O3,并利用上述設(shè)備研究了C3H8O3對(duì)膜層硬度、厚度、相結(jié)構(gòu)、表面形貌和耐蝕性的影響。最后,本文結(jié)合試驗(yàn)結(jié)果對(duì)微弧氧化膜層形成過程進(jìn)行了初步的探討。實(shí)驗(yàn)結(jié)果表明:隨著氧化時(shí)間增加,膜層的厚度不斷增大,最大達(dá)到25.0μm,膜層表面粗糙度不斷增大。隨著電流密度和Na2SiO3濃度的增加,膜層都呈先變致密后變粗糙的趨勢(shì)。厚度隨電流密度的增大而增大,而隨Na2SiO3濃度的增加呈先增大后減小的趨勢(shì)。XRD圖譜分析表明,增大電流密度和氧化時(shí)間使膜層中的金紅石型TiO2含量增加,相比改變Na2SiO3濃度,能更明顯地改變相組成。氧化時(shí)間由30min增加到40min,金紅石型TiO2含量增加,硬度提高;氧化時(shí)間由40min增加到50min,膜層致密性降低,硬度降低。增大Na2SiO3濃度,硬度的趨勢(shì)和增大氧化時(shí)間的相同。隨著電流密度的增加,膜層硬度不斷增大。隨著氧化時(shí)間的增加,膜層硬度提高使耐磨性增強(qiáng),當(dāng)氧化時(shí)間為50min,膜層硬度降低、表面粗糙程度增加使耐磨性降低。增加電流密度,膜層的硬度和致密度增大,耐磨性提高,當(dāng)電流密度增加到14A/dm2,膜層疏松層增加,耐磨性降低。增加Na2SiO3濃度,膜層表面的粗糙程度降低,耐磨性提高,當(dāng)Na2SiO3濃度增加到6g/L時(shí),膜層中的Na2SiO3含量升高,使粘著磨損加劇,耐磨性降低。膜層極化曲線分析結(jié)果表明,增大氧化時(shí)間,膜層的自腐蝕電流密度由7.62×10-7A/cm2減小到3.91×10-7A/cm2,后增大到6.82×10-7A/cm2,耐蝕性先增大后減小,增大電流密度表現(xiàn)出相同的規(guī)律。而隨著Na2Si03濃度的提高,膜層自腐蝕電流密度由9.16×10-8A/cm2增大到1.72×10-7A/cm2,耐蝕性不斷降低。增大C3H8O3濃度使膜層的硬度和厚度均表現(xiàn)出先增大后減小的趨勢(shì)。從微觀形貌可知,C3H8O3能夠減輕尖端放電效應(yīng),防止膜層邊緣被燒蝕。膜層的均勻性隨C3H8O3濃度提高呈現(xiàn)先升高后降低的趨勢(shì)。XRD圖譜分析結(jié)果表明,C3H8O3并不能改變膜層的相結(jié)構(gòu)。極化曲線分析結(jié)果表明,隨著C3H8O3濃度的增大,膜層的自腐蝕電流密度由5.59×10-7A/cm2降低到2.54×10-8A/cm2,當(dāng)C3H8O3濃度為6ml/L時(shí),膜層的自腐蝕電流密度增大到2.43×10-7A/cm2,膜層的耐蝕性表現(xiàn)為先增大后減小。C3H803能夠使膜層表面的含Si離子濃度增大,提供更多的放電中心,使膜層生長(zhǎng)速度加快、致密度提高,改善膜層性能。但是,C3H8O3濃度過高,膜層性能下降。對(duì)試驗(yàn)數(shù)據(jù)進(jìn)行多項(xiàng)式擬合,得出膜層生長(zhǎng)動(dòng)力學(xué)曲線:T=-4.577+1.322t-0.0148t2,并通過了 F檢驗(yàn)和t檢驗(yàn)。從曲線中可以得知:在微弧氧化膜層的生長(zhǎng)過程中,生長(zhǎng)速率不斷下降。微弧氧化初始階段,作用于膜層表面的電場(chǎng)強(qiáng)度大于1.26×108V/m,膜層阻擋層生長(zhǎng),當(dāng)大于擊穿電場(chǎng)時(shí),開始起弧。起弧后,由于邊緣位置具有更高的電場(chǎng)和界面能,發(fā)生邊緣放電效應(yīng)。從熱力學(xué)的觀點(diǎn)看,膜層中可能存在不飽和氧化物和AlPO4。
[Abstract]:Titanium alloy with its high specific strength, good biocompatibility and good etc. are widely used in aviation, aerospace, medical and other fields, but the poor wear resistance, low hardness limits the application of titanium alloys. Micro arc oxidation technology provides a good solution for solving these problems. This paper chooses TC4 titanium alloy is the most widely used as the matrix material, influence of process parameters on the structure and properties of TC4 titanium alloy by micro arc oxidation, provide a theoretical basis for the application of titanium alloy film industry investment, broaden the scope of application of the titanium alloy. This paper uses the constant current mode of microarc oxidation of TC4 titanium alloy based electrolyte salts in Na2SiO3 and Na3PO4, were studied effect of current density, oxidation time and Na2SiO3 concentration on the structure and properties of the coatings. The film thickness gauge using eddy current, film thickness and hardness, micro hardness were studied using Vivtorinox SEM, XRD, Study on the microstructure of EDS coating, phase composition, chemical composition, study on the corrosion resistance of the film prepared by electrochemical workstation, using a ball on disk tribometer and EDS on the wear resistance of the coatings. Adding C3H8O3 based on the optimum parameters of the equipment, and use of C3H8O3 on the hardness of the film thickness. Effect, phase structure, surface morphology and corrosion resistance. Finally, this paper combined with the test results of a preliminary study of the formation of the MAO coatings. The experimental results show that with the increase of oxidation time, film thickness increasing, the maximum reached 25 m, the surface roughness increases with the increase of current density and. The concentration of Na2SiO3, the film was rough trend becomes dense. First thickness increases with increasing current density, and with the increase of Na2SiO3 concentration of.XRD showed a trend of first increase and then decrease analysis Show that the increase of current density and oxidation time of the rutile TiO2 content in the film increases, compared to changes in Na2SiO3 concentration can significantly change the phase composition. The oxidation time increased from 30min to 40min, increased the content of rutile TiO2 hardness increased; oxidation time is increased from 40min to 50min, reduce the film density decreased and hardness. The concentration of Na2SiO3 increased, the hardness of the trend and increase the oxidation time. The same as the current density increases, the hardness increases. With the increase of oxidation time, the hardness to enhance wear resistance, when the oxidation time is 50min, the hardness decreased, the surface roughness increases the wear resistance decreased. The current density increases, the film the hardness and the density increases, the wear resistance increases, when the current density increased to 14A/dm2, the film layer is increased, the wear resistance decreased. The increase of Na2SiO3 concentration, the roughness of film surface reduction Low, the wear resistance increases, when the concentration of Na2SiO3 increased to 6g/L, increased Na2SiO3 content in the film, adhesion wear, wear resistance decreased. The film polarization curve analysis results show that the increase of oxidation time, the corrosion current density decreases from 7.62 * 10-7A/cm2 to 3.91 * 10-7A/cm2 film, then increased to 6.82 * 10-7A/cm2. The corrosion resistance increased firstly and then decreased with increasing the current density showed the same regularity. With the increase of the concentration of Na2Si03, the corrosion current density increased to 1.72 from 9.16 * 10-8A/cm2 * 10-7A/cm2, the corrosion resistance decreases with increasing C3H8O3 concentration. The film thickness and hardness showed first increased and then decreased from the micro. The morphology shows that C3H8O3 can reduce the discharge effect, prevent the film edge ablation coating uniformity. With the increase of C3H8O3 concentration of.XRD showed a trend of decrease after the first rise analysis results show that C 3H8O3 does not change the phase structure of the coatings. The polarization curve analysis results show that with the increase of C3H8O3 concentration, the corrosion current density by 5.59 * 10-7A/cm2 * 10-8A/cm2 film is reduced to 2.54, when the C3H8O3 concentration is 6ml/L, the coating corrosion current density increases to 2.43 * 10-7A/cm2, the corrosion resistance of the film was first increased after the decrease of.C3H803 can make the film surface containing Si ion concentration increases, providing more discharge, the film growth speed, improve the density and improve the film performance. However, the high concentration of C3H8O3, properties of the film decreased. Fitting the test data, the film growth kinetics curve: T=-4.577+1.322t-0.0148t2, and through F test and t test. We can learn from the curve: in the growth process of micro arc oxidation coating, the growth rate is declining. The initial stage of micro arc oxidation film, acting on the table The electric field intensity greater than 1.26 x 108V/m film, barrier layer growth, when more than the breakdown field, start arc. The arc, the edge position has higher electric field and the interfacial energy, the occurrence of edge effect. The discharge from the thermodynamic point of view, the film may exist in unsaturated oxygen complexes and AlPO4.

【學(xué)位授予單位】：西南石油大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TG174.4

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李興照;吳連波;;脈沖頻率對(duì)鈦合金微弧氧化膜層性能的影響[J];長(zhǎng)春工業(yè)大學(xué)學(xué)報(bào);2016年05期

2 夏申琳;王剛;楊曉;李雪峰;王明建;;鈦及鈦合金在船舶中的應(yīng)用[J];金屬加工(冷加工);2016年19期

3 沈雁;王紅星;;納米MoS_2顆粒對(duì)海洋平臺(tái)鋁合金鉆探管表面微弧氧化膜的性能影響[J];船舶工程;2016年07期

4 吳連波;馬維紅;李興照;;鈦合金微弧氧化電解液及添加劑的研究進(jìn)展[J];長(zhǎng)春工業(yè)大學(xué)學(xué)報(bào);2015年02期

5 李明哲;牛宗偉;;不同電流密度下TC4鈦合金微弧氧化膜的電化學(xué)腐蝕行為[J];電鍍與環(huán)保;2015年02期

6 金和喜;魏克湘;李建明;周建宇;彭文靜;;航空用鈦合金研究進(jìn)展[J];中國(guó)有色金屬學(xué)報(bào);2015年02期

7 吳文昊;;TC4鈦合金微弧氧化工藝參數(shù)對(duì)膜層性能影響的研究[J];熱加工工藝;2014年08期

8 李明哲;牛宗偉;徐明玉;;電流密度對(duì)TC4鈦合金微弧氧化陶瓷膜性能的影響[J];電鍍與涂飾;2014年07期

9 王淑艷;夏永平;劉莉;;C_3H_8O_3含量對(duì)AZ91D鎂合金微弧氧化過程及膜層特性的影響[J];中國(guó)腐蝕與防護(hù)學(xué)報(bào);2013年03期

10 吳云峰;楊鋼;裴崇;盧德宏;張?zhí)K;李榮雙;;電解液溫度對(duì)TC4鈦合金微弧氧化膜層性能的影響[J];鑄造技術(shù);2013年05期

相關(guān)博士學(xué)位論文 前2條

1 唐元廣;TC4鈦合金微弧氧化膜的制備表征及陰極微弧放電機(jī)制研究[D];吉林大學(xué);2009年

2 吳漢華;鋁、鈦合金微弧氧化陶瓷膜的制備表征及其特性研究[D];吉林大學(xué);2004年

相關(guān)碩士學(xué)位論文 前10條

1 孫大超;鈦合金微弧氧化表面改性研究[D];北方工業(yè)大學(xué);2016年

2 王浩;微/納米顆粒增強(qiáng)鋁合金微弧氧化層的制備和性能研究[D];大連海事大學(xué);2015年

3 吳云峰;醫(yī)用鈦合金微弧氧化陶瓷層制備工藝及性能研究[D];昆明理工大學(xué);2013年

4 楊昆昆;電參數(shù)及納米SiC顆粒對(duì)Ti6Al4V微弧氧化膜層的影響[D];太原理工大學(xué);2013年

5 張中元;鈦合金微弧氧化膜制備工藝及應(yīng)用研究[D];上海交通大學(xué);2012年

6 歐r，

本文編號(hào)：1489657