本文選題：鎂空氣電池 + 稀土鎂合金��； 參考：《河南工業(yè)大學(xué)》2017年碩士論文

【摘要】：鎂及鎂合金具有密度低、電化學(xué)活性高、標(biāo)準(zhǔn)電極電位較負(fù)和電池能量密度高等優(yōu)異性能,使鎂合金在化學(xué)電源領(lǐng)域具有非常好的發(fā)展前景而作為研究的熱點。然而因為鎂合金的自腐蝕析氫反應(yīng)嚴(yán)重與放電平臺不穩(wěn)定等問題,在很大程度上阻礙了鎂合金負(fù)極材料的廣泛應(yīng)用。本文通過對AZ31鎂合金及添加稀土元素(Y、Gd)制備的新型稀土鎂合金的電化學(xué)性能和鎂-空氣電池放電性能做了一系列的研究,為研究出高性能鎂合金負(fù)極材料提供參考依據(jù)。本論文采用線性掃描伏安曲線(LSV)、塔菲爾極化曲線(Tafel)、電化學(xué)阻抗譜(EIS)、金相實驗、XRD分析及電池恒流放電等方法,主要研究了AZ31及添加Y、Gd稀土元素制備的新型鎂合金的金相顯微組織和電化學(xué)性能,并將新型鎂合金電極與MnO2體系的空氣電極以及3.5wt%NaC l電解液組成鎂空氣電池單體,分別測試其在5mA/cm2、10mA/cm2和20mA/cm2電流密度下的放電電壓隨放電時間的變化規(guī)律,并研究電池的恒流放電性能。主要研究結(jié)果如下:(1)AZ31中添加不同的稀土元素,制備AZ31-Y和AZ31-Y-Gd稀土鎂合金。三類新型鎂合金的金相實驗和電化學(xué)性能測試中,AZ31-Y-Gd合金的組織均勻且晶粒尺寸相對最小,晶粒細(xì)化效果明顯,電極的平衡電位較負(fù)且電化學(xué)活性相對較高,耐腐蝕性能最好;鑄態(tài)AZ31合金的平衡電位相對較正、電荷傳遞過程的電阻較小,電極的耐腐蝕性最差。(2)AZ31、AZ31-Y及AZ31-Y-Gd鎂負(fù)極組裝的鎂空氣電池,其開路電壓非常接近在1.60V左右。在5mA/cm2、10mA/cm2和20mA/cm2電流密度條件下放電,三類鎂合金材料均在10mA/cm2電流密度下,表現(xiàn)出較高的放電平臺和較好的放電平穩(wěn)性等綜合放電性能。三種新型鎂負(fù)極空氣電池在10mA/cm2電流密度下,AZ31-Y-Gd放電電壓相對最高且放電過程電壓平穩(wěn)下降,總體放電效果最好;AZ31放電電壓最低,且放電電壓波動范圍較大。(3)AZ31中添加不同含量的稀土元素Y和Gd,制備AZ31-x%RE稀土鎂合金。隨稀土含量的增加,組織中出現(xiàn)新相Al2Gd、Al2Y和Mg24Y5,組織中析出相數(shù)量增加,晶粒尺寸逐漸減小,基體組織明顯細(xì)化。當(dāng)稀土(Y+Gd)含量為3%時,AZ31-3%RE具有最小的晶粒尺寸和均勻的組織;電化學(xué)性能測試表明,AZ31-3%RE擁有較負(fù)的平衡電位,較高的電化學(xué)活性,在3.5wt%NaCl中的耐腐蝕性能最好,AZ31-2%RE合金表現(xiàn)出的電化學(xué)性能次之,AZ31-1.5%RE的平衡電位較正且電荷傳遞電阻較小,電化學(xué)性能較差。(4)三種AZ31-x%RE鎂負(fù)極空氣電池的開路電壓相差不大,電壓值在1.60V左右。在10mA/cm2放電電流密度下,AZ31-3%RE放電電壓在1.0V左右且放電較平穩(wěn);AZ31-2%RE與AZ31-3%RE放電電壓相當(dāng),但電壓略有波動;AZ31-1.5%RE放電電壓最低,且放電后期電壓周期性波動劇烈,綜合放電性能最差。
[Abstract]:Magnesium and magnesium alloys have low density, high electrochemical activity, negative electrode potential and high battery energy density, which make magnesium alloys have a very good prospect in the field of chemical power supply. However, due to the serious self-corrosion hydrogen evolution reaction and unstable discharge platform of magnesium alloys, the wide application of magnesium alloy anode materials is hindered to a great extent. In this paper, a series of studies have been done on the electrochemical properties of AZ31 magnesium alloy and the new rare earth magnesium alloy prepared by adding rare earth element, and the discharge performance of magnesia-air battery, which provides a reference for the study of high performance magnesium alloy negative electrode material. In this paper, the linear scanning voltammetry curve (LSVN), Tafer polarization curve (Tafel), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) analysis and constant current discharge of the battery were used. The metallographic microstructure and electrochemical properties of the new magnesium alloy prepared by AZ31 and YTGd rare earth element were studied. The new magnesium alloy electrode, the air electrode of MnO2 system and the 3.5wt%NaC l electrolyte were used to form the Mg-air battery monomer. The variation of discharge voltage with discharge time at 5 Ma / cm 2 10 Ma / cm 2 and 20mA/cm2 current density was measured, and the constant current discharge performance of the battery was studied. The main results are as follows: AZ31-Y and AZ31-Y-Gd rare earth magnesium alloys were prepared by adding different rare earth elements into AZ31. In the metallographic test and electrochemical performance test of three kinds of new magnesium alloys, the microstructure of AZ31-Y-Gd alloy is uniform, the grain size is relatively small, the effect of grain refinement is obvious, the equilibrium potential of electrode is relatively negative, the electrochemical activity is relatively high, and the corrosion resistance is the best. The equilibrium potential of as-cast AZ31 alloy is relatively positive, the resistance of charge transfer process is smaller, and the corrosion resistance of the electrode is the worst. The open-circuit voltage of the magnesium-air battery assembled by AZ31AZ31-Y and AZ31-Y-Gd negative electrode is very close to 1.60V. Under the conditions of 5 Ma / cm 2 10 Ma / cm 2 and 20mA/cm2 current density, the three kinds of magnesium alloys exhibit high discharge platform and good discharge stability at 10mA/cm2 current density. The discharge voltage of AZ31-Y-Gd is the highest at 10mA/cm2 current density, and the voltage of discharge process decreases steadily, the overall discharge effect is the best and the discharge voltage of AZ31 is the lowest. AZ31-x%RE rare earth magnesium alloy was prepared by adding different contents of rare earth elements Y and Gd in the range of voltage fluctuation. With the increase of rare earth content, new phases Al _ 2Gd _ 2O _ (Al _ 2Y) and mg _ (24) Y _ 5 appear in the microstructure. The number of precipitated phases in the microstructure increases, the grain size decreases gradually, and the matrix structure is refined obviously. AZ31-3RE has the smallest grain size and uniform structure when the content of rare earth is 3, and the electrochemical performance test shows that AZ31-3RE has negative equilibrium potential and high electrochemical activity. The corrosion resistance of AZ31-2RE alloy is the best in 3.5wt%NaCl. The second is the electrochemical performance of AZ31-1.5RE alloy. The equilibrium potential of AZ31-1.5RE is higher, the charge transfer resistance is smaller, and the electrochemical performance is poor. The voltage is about 1.60 V. Under the current density of 10mA/cm2 discharge, the discharge voltage of AZ31-3RE is about 1.0 V, and the discharge voltage of AZ31-2RE is about the same as that of AZ31-3%RE discharge voltage, but the voltage fluctuates slightly and the voltage of AZ31-1.5RE discharge is the lowest, and the voltage of AZ31-3RE at the later stage of discharge fluctuates sharply, and the comprehensive discharge performance is the worst.
【學(xué)位授予單位】：河南工業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TG146.22;TM911.41

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 陳強(qiáng)強(qiáng);宋廣勝;徐勇;張士宏;;孿晶和解孿晶對AZ31鎂合金力學(xué)性能的影響[J];特種鑄造及有色合金;2015年03期

2 胡啟明;張婭;陳秋榮;;鎂電池研究進(jìn)展[J];電源技術(shù);2015年01期

3 鄧金鳳;黃光勝;趙炎春;王蓓;;不同加工狀態(tài)AZ31鎂合金電化學(xué)性能研究（英文）[J];稀有金屬材料與工程;2014年02期

4 任峻;馬穎;陶欽貴;;固溶時效處理對觸變成形AZ91D鎂合金組織和性能的影響研究[J];稀有金屬與硬質(zhì)合金;2013年02期

5 朱明駿;袁振善;桑林;丁飛;劉浩杰;;金屬/空氣電池的研究進(jìn)展[J];電源技術(shù);2012年12期

6 谷松偉;郝海;張愛民;宋迎德;張興國;;Gd對鑄態(tài)AZ31合金組織和性能的影響[J];特種鑄造及有色合金;2011年05期

7 閆愛軍;馮拉俊;王紫鵬;;Influence of yttrium addition on properties of Mg-based sacrificial anode[J];Journal of Rare Earths;2010年S1期

8 余琨;宋覺敏;蔡志勇;楊軍;薛新穎;雷路;;鎂及鎂合金電池陽極材料的研究、開發(fā)及應(yīng)用[J];金屬功能材料;2010年04期

9 張代東;康云;宮長偉;原洪加;閆志杰;;AZ61+xCe(x=0～1.5)合金的微觀組織研究[J];電子顯微學(xué)報;2010年01期

10 堯玉芬;陳昌國;劉渝萍;司玉軍;;鑭對AZ31鎂合金電化學(xué)行為的影響[J];中國稀土學(xué)報;2009年05期

相關(guān)博士學(xué)位論文 前1條

1 吳林;鎂鋰基合金在NaCl溶液中電化學(xué)行為的研究[D];哈爾濱工程大學(xué);2010年

相關(guān)碩士學(xué)位論文 前8條

1 滕昭陽;合金元素對鎂陽極腐蝕與電化學(xué)性能的影響[D];中南大學(xué);2014年

2 崔存?zhèn)};鋅-空氣電池空氣電極的制備及研究[D];哈爾濱工業(yè)大學(xué);2013年

3 鄧金鳳;鎂負(fù)極加工狀態(tài)與緩蝕劑對鎂空氣電池的影響[D];重慶大學(xué);2013年

4 程毅;鎂干電池負(fù)極材料和緩蝕劑的研究[D];重慶大學(xué);2012年

5 張虎;稀土鎂合金中稀土相形態(tài)對性能的影響[D];太原科技大學(xué);2011年

6 劉敏娟;稀土元素對AZ31變形鎂合金組織和性能的影響[D];太原科技大學(xué);2010年

7 張佩紅;鎂電池負(fù)極材料的電化學(xué)行為研究[D];重慶大學(xué);2009年

8 王承霞;鋅-空氣電池空氣電極研究[D];鄭州大學(xué);2004年

，

本文編號：1798430